PROGRAM
AND
ABSTRACTS OF PAPERS

JAPANESE ASSOCIATION FOR
DENTAL RESEARCH

The 68th ANNUAL MEETING
November 7-8, 2020
Virtual Meeting

CONTENTS

Officers of JADR …………………………………………………………………

4

JADR Timetable ……………………………………………………………………

5

Scientific Program …………………………………………………………………

7(Abstracts)
Keynote Lecture ……………………………………………………………………

25

Greeting ……………………………………………………………………………

29

Special Lecture ……………………………………………………………………

33

Symposium (I ~III) …………………………………………………………………

37

Rising Scientist Session ……………………………………………………………

65

Poster Presentation …………………………………………………………………

73

Author Index ……………………………………………………………………… 119
List of Sponsors …………………………………………………………………… 123

─2─

Welcome message
Dear Craniofacial and Dental Scientists:
In behalf of the organizing committee and as the Chairman of the68th Annual Meeting of Japanese Association of Dental Research(JADR) 2020, I am delighted to welcome every one of you to thismeeting. It is our great honor and pleasure to hold such a prestigious
meeting. Although conducting this meeting is very difficult becauseof the COVID-19 pandemic, we express our gratitude to the presidentof JADR, Professor Satoshi Imazato, and all of our distinguished guests for their attendance.
JADR has contributed to the advancement of basic and clinical research in the dental sciencefield in Japan, in collaboration with the International Association for Dental Research (IADR).
We have decided to designate "Beyond Borders: From Dental Research to Future Oral Health" as
the main theme of this meeting to expand the basic and clinical research and produce a newtranslational researc h for spurring evolution in dentistry.
We will invite Dr. Pamela Den Besten (from IADR) and Dr. Joo-Cheol Park (from the Korean
Division of the IADR (KADR) as Special Lecturers, who will share with us their future outlook
in regard to dental science. As for the Keynote, Professor Richard J. Lamont from the Universityof Louisville will present an interesting lecture concerning the process of dysbiosis inperiodontitis.
We will also organize three symposiums on this particular topic, entitled "At the front-line:
Etiology of periodontitis," "Pathophysiological approach from the oral function to systemic
diseases" and "Future is now! Stem cell revolution in hard and soft tissue engineering" fromwhich we reach the frontline of periodontitis, oral function from the pathophysiological
viewpoint, and stem cell research. We also organized a symposium on neuroscience for young
investigators.
Although the meeting will take place online because of the complicated COVID-19 situation, we
believe that this meeting will provide an excellent opportunity for all attendees to learn together
in the virtual world to evolve dental science through telecommunications beyond the physicaldistance.
The 68th Annual Meeting of Japanese Association for Dental Research
Congress President: Kazuyuki Ishihara, D.D.S., Ph.D.
Professor Department of Microbiology, Tokyo Dental College

─3─

OFFICERS
OFJAPANESE ASSOCIATIONFOR DENTAL RESEARCH

President ………………………………………………………………………… S. Imazato
President-elect and Vice-president ……………………………………………… S. Nakamura
Immediate Past President ……………………………………………………… K. Yamazaki
Treasurer ………………………………………………………………………… K. Moriyama
Director ………………………………………………………………………… T. Goto
Director ………………………………………………………………………… M. Honda
Director ………………………………………………………………………… K. Ikebe
Director ………………………………………………………………………… K. Ishihara
Director ………………………………………………………………………… T. Matsumoto
Director ………………………………………………………………………… M. Noda
Director ………………………………………………………………………… S. Yamada
Director ………………………………………………………………………… A. Yoshihara
Auditor ………………………………………………………………………… N. Takahashi
Auditor ………………………………………………………………………… T. Takata

Chairman, Organizing Committee ……………………………………………… K. Ishihara
Secretary-general ……………………………………………………………… Y. Shibukawa

─4─

JADR Timetable November 7th (Sat.) November 8th (Sun.)
Video On-demand distribution / Live streaming
November 7 (Sat.)

November 8 (Sat.)

9:00

10:00

10:00 〜 12:00

10:00 〜 12:30

Symposium I
At the front-line: Etiology of periodontitis
Video On-demand : 20 minutes each
Q & A Live streaming : 10 minutes each

Symposium Ⅱ
Future is now! Stem cell revolutionin hard and soft tissue engineering
Video On-demand : 20 minutes each
Q & A Live streaming : 10 minutes each

11:00
Q & A delivery time
10:20-10:30 Dr. Toru Takeshita
10:50-11:00 Dr. Masaaki Nakayama
11:20-11:30 Dr. Masayuki Tukazaki
11:50-12:00 Dr. Atsuo Amano

Q & A delivery time
10:20-10:30 Dr. Shinsuke Oba
10:50-11:00 Dr. Chisa Shukunami
11:20-11:30 Dr. Sachiko Iseki
11:50-12:00 Dr. Takashi Nakamura
12:20-12:30 Dr. Akihiro Yamashita

12:00
12:15 〜 13:00

Council Meeting / General Assembly
12:15-13:00(Live streaming)
13:00

13:00 〜 14:30

13:00 〜 15:00

Rising Scientist Session
Neuroscience

Symposium Ⅲ
Pathophysiological approachfrom oral function to systemic diseases

Video On-demand : 20 minutes each
Q & A Live streaming : 10 minutes each

14:00

Video On-demand : 20 minutes each
Q & A Live streaming : 10 minutes each

Q & A delivery time
13:20-13:30 Dr. Fumiya Kano
13:50-14:00 Dr. Ayano Katagiri
14:20-14:30 Dr. Jun Miyamoto

Q & A delivery time
13:20-13:30 Dr. Noriatsu Shigemura
13:50-14:00 Dr. Takafumi Kato
14:20-14:30 Dr. Masamichi Shinoda
14:50-15:00 Dr. Toshihide Mizoguchi

15:00

16:00

─5─

JADR Timetable
November 7th(Sat.) - 21st.(Sat.)Video On-demand and Poster File distribution

Keynote Lecture (Video On-demand distribution)
Prof. Richard J. Lamont(Department Oral Immunology & Infectious Diseases, University of Louisville, School of Dentistry)“Porphyromonas gingivalis interactions with epithelial cells in the community context”

Greeting from IADR President (Video On-demand distribution)
Prof. Pamela Den Besten(President of IADR)

Special Lecture (Video On-demand distribution)
Prof. Joo-Cheol Park
(President of KADR)“Tubular Dentin Regeneration and Its Clinical Application”

Poster Presentation (On-demand distribution of presentation file (PDF))

─6─

November 7th, Saturday, ~ November 21st, Saturday
Keynote Lecture(Video On-demand distribution)KL

Porphyromonas gingivalis interactions with epithelial cells in the community context
Dr. Richard J Lamont(Department Oral Immunology & Infectious Diseases, University of Louisville, School of Dentistry)

Greeting from IADR President(Video On-demand distribution)
G
Dr. Pamela Den Besten(Department of Orofacial Sciences, School of Dentistry, University of California San Francisco)Special Lecture(Video On-demand distribution)
SL

Tubular Dentin Regeneration and Its Clinical Application
Dr. Joo-Cheol Park
(Laboratory for the Study of Regenerative Dental Medicine, Department Oral Histology-Developmental
Biology, School of Dentistry, Seoul National University)

Symposium Ⅰ~Ⅲ, Rising Scientist Session(Lecture;Video On-demand distribution / Q & A;Live streaming)

─7─

November 7th, Saturday
10:00-12:00 Symposium I“At the front-line: Etiology of periodontitis”

SⅠ-1

SⅠ-2

SⅠ-3

SⅠ-4

Moderator: Dr. Kazuyuki Ishihara(Department of Microbiology, Tokyo Dental College, Tokyo, Japan)
Moderator: Dr. Yoshihisa Yamashita(Section of Preventive and Public Health Dentistry, Division of Oral Health,Growth and Development, Faculty of Dental Science, Kyushu University, Fukuoka, Japan)
Bacterial composition of overall oral microbiota associated with periodontal disease and health.
Dr. Toru Takeshita(Section of Preventive and Public Health Dentistry, Faculty of Dental Science, Kyushu University)
The significant role of Porphyromonas gingivalis “Gingipains” as a virulence factor on periodontal
inflammation
Dr. Masaaki Nakayama1, Dr. Naoya Ohara2(1Department of Microbiology, Graduate school of Medicine, Dentistry and Pharmaceutical Sciences,
Okayama University, 2Advanced Research Center for Oral and Craniofacial Sciences (ARCOCS),
Dental School, Okayama University)
Periodontitis as an “osteoimmune” disease
Dr. Masayuki Tsukazaki(Department of Immunology, Graduate School of Medicine and Faculty of Medicine,
The University of Tokyo)
Epithelial barrier breakdown by Porphyromonas gingivalis
Dr. Atsuo Amano, Dr. Hiroki Takeuchi(Department of Preventive Dentistry, Graduate School of Dentistry, Osaka University)

13:00-14:30 Rising Scientist Session“Neuroscience”
Moderator: Dr. Tazuko Goto
(Department of Oral and Maxillofacial Radiology, Tokyo Dental College, Tokyo, Japan)
RS-1 Factors secreted from dental pulp stem cells show multifaceted benefits for Synergistically
Regenerate Transected Rat Peripheral Nerves by Altering Macrophage Polarity.
Dr. Fumiya Kano
(Department of Tissue regeneration Institute of Biomedical Sciences, Tokushima University Graduate
School)RS-2 Phenotypic and neuroplastic changes in trigeminal nociceptive pathways following trigeminal nerve
injuryDr. Ayano Katagiri(Department of Oral Physiology, Osaka University Graduate School of Dentistry, Suita, Japan)
RS-3 The human brain and mastication; broad impact on systemic functions
Dr. Jun Miyamoto

─8─

(Department of Maxillofacial Orthognathics, Graduate School of Medical and Dental Sciences,
Tokyo Medical and Dental University (TMDU))

─9─

November 8th, Sunday
10:00-12:30 SymposiumⅡ“Future is now! Stem cell revolution in hard and soft tissue engineering”
Moderator: Dr. Toshifumi Azuma(Department of Biochemistry, Tokyo Dental College, Tokyo, Japan)
Moderator: Dr. Shinsuke Oba(Department of Cell Biology, Institute of Biomedical Sciences, Nagasaki University)
SⅡ-1 Generation of skeletal cells from pluripotent stem cells
Dr. Shinsuke Oba(Department of Cell Biology, Institute of Biomedical Sciences, Nagasaki University)
SⅡ-2 Establishment of an in vitro culture system for tenogenic/ligamentogenic differentiation using
ScxGFP iPS cells
Dr. Chisa Shukunami(Department of Molecular Biology and Biochemistry, Graduate School of Biomedical and Health Sciences,
Hiroshima University)
SⅡ-3 Classification and pathological mechanisms of Craniosynostosis based on the differentiation patternof iPS cells
Dr. Sachiko Iseki(Section of Molecular Craniofacial Embryology, Tokyo Medical & Dental University Graduate School of
Medical and Dental Sciences)
SⅡ-4 Molecular mechanisms of craniosynostosis in Apert syndrome.
Dr. Takashi Nakamura1, Dr. Hiroyuki Ogura2(1Department of Biochemistry/Research Branding Project, Tokyo Dental College.,
Department of Orthodontics, Tokyo Dental College.,2
Department of Biochemistry/Oral Health Science Center/Research Branding Project, Tokyo Dental
College.)
SⅡ-5 Application of iPS cell technologies to treat skeletal disease
Dr. Akihiro Yamashita, Dr. Noriyuki Tsumaki(Centre for iPS cell Research and Application (CiRA), Kyoto University, Japan)

13:00-15:00 Symposium Ⅲ“Pathophysiological approach from oral function to systemic diseases”
Moderator: Dr. Yoshiyuki Shibukawa(Department of Physiology, Tokyo Dental College, , Tokyo, Japan)
Moderator: Dr. Naofumi Uesaka(Department of Cognitive Neurobiology, Graduate School of Medical and Dental Sciences,
Tokyo Medical and Dental University, Tokyo, Japan)
SⅢ-1 Taste renin-angiotensin system may contribute to the maintenance of sodium homeostasis.
Dr. Noriatsu Shigemura(Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu University,,
Research and Development Center for Five-Sense Devices, Kyushu University.)
SⅢ-2 Pathophysiology of SB: challenges from human and animal studies

─ 10 ─

Dr. Takafumi Kato
(Osaka University Graduate School of Dentistry, Department of Oral Physiology)
SⅢ-3 Common pathophysiological features in burning mouth syndrome and irritable bowel syndrome
Dr. Masamichi Shinoda(Department of Physiology, Nihon University School of Dentistry)
SⅢ-4 In vivo Dynamics of Dental Tissue Regeneration
Dr. Toshihide Mizoguchi(Oral Health Science Center, Tokyo Dental College, Tokyo, Japan)

─ 11 ─

Poster Presentation
Dental Materials 1: Ceramic-based Materials
001: Wear Resistance of Novel Machinable Glass Ceramics
S. Kariya, T. Azuma, F. Fusejima
R&D Dept., GC Corporation, Tokyo, JAPANDental Materials 4: Adhesion
002: Evaluation of bonding layer durability on 2-step self-etch adhesive
K. FUJIMORI, K. HIRANO, F. FUSEJIMARESEARCH & DEVELOPMENT, GC CORPORATION, TOKYO, Japan

003: Bonding properties of acrylic resin to zirconia and polyaryletherketone (PAEK)

T.-Y. PENG1, S. SHIMOE2, D.-J. LIN1, M. KAKU2School of Dentistry, College of Dentistry, China Medical University, Taiwan R.O.C, 2Departmentof Anatomy and Functional Restorations, Hiroshima University Graduate School of Biomedical &Health Sciences, Hiroshima, Japan
1004: Bond strength between one-step adhesives and dentin after cyclic loading

T. EGOSHI1, Y. TAIRA1, K. SOENO2, K. KAIDA1, S. KUBO1, H. MURATA3
Division of Cariology and Restrative Dentistry, Department of Prosthetic Dentistry, Nagasaki
University, Nagasaki, Japan, 2Department of Appried Prosthodontics, Nagasaki University, Nagasaki,
Japan, 3Department of Prosthetic Dentistry, Nagasaki University, Nagasaki, Japan

1005: Influence of saliva contamination on adhesion performance of adhesive resin cement
S. MURAKAMI, K. HIRANO, F. FUSEJIMARESEARCH & DEVELOPMENT, GC CORPORATION, TOKYO, Japan.

Cariology Research-Demineralization/Remineralization
006: Evaluation of Dentin Anti-Demineralization potential of S-PRG Containing SelfAdhesive Resin Cement

S. ThanNaing1, N. Hiraishi1, A. Abdou1,3, J. Tagami1
Cariology and Operative Department, Tokyo Medical and Dental University, Tokyo, JAPAN,
2
Department of Conservative Dentistry, University of Dental Medicine Mandalay, Mandalay,
Chanmyathazi, MYANMAR, 3Biomaterials Department, Faculty of Dentistry, Modern University forTechnology and Information, Cairo, EGYPT
1

007: Preparation of Filler-Dispersed Resin Composite for Additive Manufacturing

P. KARNTIANG1, H. IKEDA2, Y. NAGAMATSU2, H. SHIMIZU2
1
Division of Operative Dentistry, College of Dentistry, Rangsit University, Pathum Thani, Thailand,
2
Division of Biomaterials, Department of Oral Functions, Kyushu Dental University.

008: Enamel Remineralization of TCP with Fluoride in Toothpaste: EPMA Study

H. HAMBA, H. ISHIZUKA, Y. MIYAYOSHI, K. NAKAMURA, T. MURAMATSU
Department of Operative Dentistry, Cariology and Pulp Biology, Tokyo Dental College, Tokyo, Japan─ 12 ─

009: EVALUATION OF THE EFFECT OF ZINC-CONTAINING ORAL MATERIALSON REMINERALIZATION USING IN-AIR MICROBEAM PIXE/PIGE
M. Sakurai1, Y. Matsuda2, K. Okuyama3, H. Yamamoto2, M. Hayashi2, T. Saito1
Division of Clinical Cariology and Endodontology, Department of Oral Rehabilitation, Health
Sciences University of Hokkaido, Tobetsu-cho, Ishikari-gun, Hokkaido, JAPAN, 2Department ofRestorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, Osaka,
JAPAN, 3Department of Dental Materials Science, Asahi University School of Dentistry, Mizuho,
Gifu, JAPAN1

Cariology Research-Fluoride & Ca-based Products
010: Dynamics of Ions Artificially Introduced into Caries-affected Dentin

K. NAITO1, H. YAMAMOTO1, Y. MATSUDA2, K. OKUYAMA3, M. HAYASHI1
1
Department of Restrative Dentistry and Endodontology, Osaka University Graduate School of
Dentistry, 2Division of Clinical Cariology and Endodontology, Department of Oral Rehabilitation,
School of Dentistry, Health Sciences University of Hokkaido, 3Department of Dental Materials
Science, Division of Oral Functional Sciences and Rehabilitation, Asahi University School of
Dentistry

Dental Materials 2: Polymer-based Materials
011: Physical properties of Resorbable P(LA/CL) bilayer membrane for GBR
Y. SAKAGUCHI, E. ARIMA, K. YAMANAKA, F. FUSEJIMAGC Corporation, Tokyo, Japan

Prosthodontics Research
012: Influence of Molding Angle on 3D-printed Partial Denture Framework

H. KOBAYASHI1, A. TASAKA1, T. SHIMIZU1, S. HIGUCHI2, S. YAMASHITA1
1
Department of Removable Partial Prosthodontics, Tokyo Dental College, 2Wada Precision Dental
Laboratories Corporation

Oral Health Research013: Microbicidal effect and storage stability of neutral electrolyzed water-based gels

Y. NAGAMATSU1, H. NAGAMATSU2, H. IKEDA1, H. SHIMIZU1Division of Biomaterials, Department of Oral Functions, Kyushu Dental University, Fukuoka, Japan,
2
Division of Comprehensive Dentistry, Department of Oral Functions, Kyushu Dental University,
Fukuoka, Japan

1

014: A pilot study of effects on Dentifrice Containing Neem for Oral Malodor, PlaqueAdhesion, Gingival Inflammation and Oral Bacteria

M. YASUI, K. SHINADA
Department of Priventive Oral Health Care Sciences, Tokyo Medical and Dental University, Tokyo,
Japan

Microbiology/Immunology
015: Antimicrobial effects and mechanical properties of acrylic resin containing aPIZAS

K. INABA1, H. WATANABE1, Y. WADA1, S. WATANABE1, H. SASAKI1, H. HIRAMINE2, M.
SASAKI3, T. NIHEI1, N. HAMADA1
1
Department of Oral Science, Kanagawa Dental University, Yokosuka, Japan, 2Department of Highly─ 13 ─

Advanced Stomatology, Yokohama Clinical Education Center of Kanagawa Dental University,
3
Nissho Chemistry Corporation

016: Effects of S-PRG eluate on bacterial properties related to oral malodor

S. OMAGARI1, M. YONEDA1, N. SUZUKI2, D. GRENIER3, S. YAMAMOTO1, K. YAMADA1, J.
HATAKEYAMA1, H. MORITA4, C. KOGA5, T. HIROFUJI1
1
Section of General Dentistry, Department of General Dentistry, Fukuoka Dental College, Fukuoka,
Japan, 2Section of Oral Public Health, Department of Preventive and Public Health, Fukuoka Dental
College Fukuoka, Japan, 3Groupe de Recherche en Ecologie Buccale, Faculte de medecine dentaire,
Universite Laval, Quebec, Canada, 4The Center for Visiting Dental Service, Department of General
Dentistry, Fukuoka Dental College, Fukuoka, Japan, 5Center for Oral Diseases, Fukuoka Dental
College Fukuoka, Japan

017: Evaluation of anti-biofilm effects of bio-active GIC using a bioreactor

T. KOHNO, Y. LIU, F. DENG, R. TSUBOI, H. KITAGAWA, S. IMAZATO
Department of Biomaterials Science, Osaka University Graduate School of Dentistry, Suita, Japan

018: Streptococcus mutans inhibition by toothbrush monofilament with surface prereacted glass-ionomer
S. MATAYOSHI, T. KITAMURA, M. OTSUGU, R. NOMURA, K. NAKANO
Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Japan

019: Comparison of microbiome organized on denture base materials and hydroxyapatite
Y. NEZU1, M. RYU1, K. ISHIHARA2, T. UEDA1
1
Removable Prosthodontics & Gerodontology, Tokyo Dental College, Tokyo, Japan, 2Microbiology,
Tokyo Dental College

Cariology Research-Microbiological Studies/Biofilm
020: ABC transporter activities in biofilm formation by Streptococcus mutans

K. GOTO, M. MATSUMOTO-NAKANO
Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry andPharmaceutical Sciences, Okayama, Japan

Microbiology/Immunology
021: Inhibitory Effect of Cyclodextran on Glucosyltransferase B in Streptococcus mutans

H. ASAUMI, K. GOTO, M. MATSUMOTO-NAKANO
Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry andPharmaceutical Sciences, Okayama, Japan

022: The effects of fatty acid salts against Streptococcus mutans biofilm

A. KURAHASHI, K. WATANABE, T. SATO, K. INABA, H. SASAKI, N. HAMADA
Department of Oral Science, Graduate School, Kanagawa Dental University

023: Evaluation of collagen-binding properties of killed Streptococcus mutans strains

Y. SUEHIRO, S. MATAYOSHI, M. OTSUGU, R. NOMURA, K. NAKANO
Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Osaka, Japan

024: Screening of S. salivarius isolates with anti-caries activities

H. NAKADE1, S. ALI2, D. DUFOUR2, C. LEVESQUE2, S. GONG2Faculty of Dentistry, Tokyo Medical and Dental University, 2Faculty of Dentistry, University ofToronto1

─ 14 ─

025: Characteristics of anti-periodontal bacterial activity in culture supernatant ofprobiotic

T. KAWAI1, R. SHIN2, Y. ITO2, S. IKAWA3, T. TANAKA3, T. OHSHIMA1
1
Department of Oral Microbiology, Tsurumi University School of Dental Medicine, Kanagawa, Japan,
2
ALA Research Institute for Fermentative Microbes, Tokyo, Japan, 3Technology Research Institute of
Osaka Prefecture, Osaka, Japan

Periodontal Research-Pathogenesis
026: Exploring for prevention of periodontal disease using products of the probiotic
bacteria, genus Lactobacillus -Targeting the genus PorphyromonasY. SAKAI, T. OHSHIMA, T. KAWAI
Tsurumi University Faculty of Dentistry Department of Dentistry

Microbiology/Immunology
027: Gemella haemolysans specifically inhibits the growth of Porphyromonas gingivalis

T. MIYOSHI1, N. YOSHINARI2, A. YOSHIDA1
1
Department of Oral Microbiology, Matsumoto Dental University, Nagano, Japan, 2Department of
Periodontology, Matsumoto Dental University, Nagano, Japan

028: Fusobacterium nucleatum metabolically integrates commensals and pathogens in oral
biofilms
A. SAKANAKA1, M. KUBONIWA1, S. SHIMMA2, S. MAYUMI1, R. LAMONT3, E. FUKUSAKI2, A.
AMANO1
1
Department of Preventive Dentistry, Osaka University Graduate School of Dentistry, Osaka, Japan,
2
Department of Biotechnology, Osaka University Graduate School of Engineering, Osaka, Japan,
3
Department of Oral Immunology and Infectious Diseases, School of Dentistry, University ofLouisville, Louisville, KY, USA

029: Analysis of novel genotypes of Mfa1 fimbriae in Porphyromonas gingivalis

K. SAKAE1, K. NAGANO2, Y. HASEGAWA1
1
Department of Microbiology, School of Dentistry, Aichi Gakuin University, Aichi, Japan,
2
Department of Microbiology, School of Dentistry, Health Sciences University of Hokkaido,
Hokkaido, Japan

030: Role of hyalin-like protein in biofilm formation by Capnocytophaga ochracea

T. WARITA1, K. SHIBAYAMA1, E. KOKUBU1, D. KITA2, Y. KIKUCHI1, K. ISHIHARA1
Department of Microbiology, Tokyo Dental College, Tokyo, Japan, 2Department of Periodontology,
Tokyo Dental College, Tokyo, Japan

1

031: The periodontopathic bacterium Fusobacterium nucleatum induced
proinflammatory cytokine production by human respiratory epithelial cells and in
the lower respiratory organs in mice

K. IMAI1, N. WATANABE1,2, S. YOKOE1,2, S. SATO2
Department of Microbiology, Nihon University School of Dentistry, 2Department of Periodontology,
Nihon University School of Dentistry1032: IgA Nephropathy-like Lesion Development in Rat Caries Model

S. NAKA1, K. WATO2, T. MISAKI3, Y. NAGASAWA4, S. ITO5, R. NOMURA2, M. MATSUMOTONAKANO1, K. NAKANO2
1
Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry─ 15 ─

and Pharmaceutical Sciences, Okayama, Japan, 2Department of Pediatric Dentistry, Division of Oral
Infection and Disease Control, Osaka University Graduate School of Dentistry, Suita, Oska, Japan,
3
Division of Nephrology, Seirei Hamamatsu General Hospital, Hamamatsu, Japan, 4Division of
Kidney and Dialysis, Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya,
Japan, 5Department of Nephrology anf Endocrinology, National Defense Medical College,
Tokorozawa, Japan

033: Effects of Helicobacter pylori Infection in Caries-induced Rats

T. KADOTA, Y. OGAYA, R. NOMURA, K. NAKANO
Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Osaka, Japan

034: Prevalence of Specific Streptococcus mutans Harbored by Non-alcoholic
Steatohepatitis Patients

K. TABATA1, S. NAKA1, S. TONOMURA2,3,4, K. NAKANO5, M. MATSUMOTO-NAKANO1
1
Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry andPharmaceutical Sciences, Japan, 2Department of Neurology, Nara City Hospital, Japan, 3Departmentof Neurology, National Cerebral and Cardiovascular Center, Japan, 4Department of Neurology,
Graduate School of Medicine and Faculty of Medicine, Kyoto University, Japan, 5Department ofPediatric Dentistry, Division of Oral Infection and Disease Control, Osaka University Graduate
School of Dentistry, Suita, Osaka, Japan

Pediatric Oral Health Research035: The Initiation and development of oral microbiome formation in Japanese healthy
infants
A. SAKURAI, H. HOMMA, N. NAGAI, T. OTA, S. SHINTANI
Department of Pediatric Dentistry, Tokyo Dental College, Tokyo, Japan

Periodontal Research-Pathogenesis036: Omics analysis defines differences in microbial community structure between periimplantitis and periodontitis

K. KOMATSU1, Y. TAKEUCHI1, T. SHIBA1, T. WATANABE2, M. SHIMOGISHI3, M.
SHIBASAKI3, T. NEMOTO1, T. KOYANAGI1, S. KATAGIRI1, T. IWATA1
1
Department of Periodontology, Graduate School of Medical and Dental Sciences, Tokyo Medical and
Dental University, Tokyo, Japan, 2Department of Chemistry, Nihon University School of Dentistry,
Tokyo, Japan, 3Department of Oral Implantology and Regenerative Dental Medicine, Tokyo Medical
and Dental University, Tokyo, Japan

037: Periodontal Bacteria Distribution in Child with Early Primary Tooth Loss

Y. MIYAI, S. NAKA, M. MATSUMOTO-NAKANOOkayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama,Japan

Periodontal Research-Therapy
038: CTLA-4 Reduces Bone Resorption Through the Inhibition of Osteoclast
Differentiation

S. NAKANE1, K. IMAMURA1, K. ISHIHARA2,3, A. SAITO1,2
1
Department of Periodontology, Tokyo Dental College, Tokyo, Japan, 2Oral Health Science Center,
Tokyo Dental College, Tokyo, Japan, 3Department of Microbiology, Tokyo Dental College, Tokyo,Japan─ 16 ─

Periodontal Research-Pathogenesis039: An immunohistochemical study on the expression of bioactive molecules in the mouse
kidney in P. gingivalis LPS-induced diabetic nephropathy
K. KOICHIRO1, Y. SAWA2, T. FUJITA1, S. TAMAOKI1
Section of orthodontics Department of Oral Growth & Development, Division of Clinical Dentistry,
Fukuoka Dental College, 2Deparment of Oral Function & Anatomy, Okayama University Graduate
School of Medicine, Dentistry, and Pharmaceutical Sciences
1

Oral Medicine & Pathology Research
040: Artepillin C regulates extracellular matrix gene expressions in human periodontal
fibroblasts by DNA methylation

R. TAKAI1, O. UEHARA2, T. MORIKAWA3, K. YOSHIDA3, J. SATO3, Y. ABIKO3, T. OHTA1
1
Advanced Research Promotion Center, Health Sciences University of Hokkaido, Hokkaido, Japan,
2
Division of Disease Control and Molecular Epidemiology, Health Sciences University of Hokkaido,
Hokkaido, Japan, 3Division of Oral Medicine and Pathology, Health Sciences University of Hokkaido,
Hokkaido, Japan

Periodontal Research-Pathogenesis
041: Exosomes from human gingiva-derived MSCs inhibit periodontal bone loss

Y. NAKAO, T. FUKUDA, Y. WATANABE, C. HAYASHI, K. KAWAKAMI, M. TOYODA, H.
YAMATO, T. SINJO, U. TANAKA, T. SANUI, F. NISHIMURA
Department of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu
University, Fukuoka, Japan

042: PPARγ is required for periodontal ligament cells to retain cemento/osteogeneity

H. YUAN1, S. SUZUKI1, A. SATO1, T. YAMAMOTO1, E. NEMOTO1, M. SAITO2, S. YAMADA1
1
The Department of Periodontology and Endodontology, Tohoku University school of Dentistry, 2The
Department of Operative Dentistry, Tohoku University school of Dentistry

Oral Medicine & Pathology Research043: Role of IQGAP1- Flightless I interaction in collagen remodeling by fibroblast

K. NAKAJIMA1, P. ARORA2, C. MCCULLOCH2
1
Department of Pathology, Tokyo Dental College, Tokyo, Japan, 2Faculty of Dentistry, University ofToronto, Toronto, ON, Canada

Periodontal Research-Therapy
044: Amelogenin down-regulates MHC class II antigen presentation on macrophages.

K. YOTSUMOTO, T. SANUI, H. YAMATO, U. TANAKA, Y. NAKAO, Y. WATANABE, C.
HAYASHI, T. FUKUDA, F. NISHIMURA
Department of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu
University, Fukuoka, Japan

Periodontal Research-Pathogenesis
045: Adipose specific C-C motif chemokine ligand (CCL) 19 overexpression drives themice to both insulin resistance and weight gain.

M. HAYASHI, M. IWASHITA, Y. NISHIMURA, T. SHINJO, T. ZEZE, T. SANO, A. YAMASHITA, F.

─ 17 ─

NISHIMURA
Department of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu
University

Periodontal Research-Therapy
046: Characterization of the PLAP-1-GFP/CreER knock-in mouse

T. IWAYAMA1, K. TOMITA1, S. MATSUMOTO1, M. IWASHITA1, C. FUJIHARA1, M.
TAKEDACHI1, S. YAMADA2, S. MURAKAMI1
1
Department of Periodontology, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan,
2
Department of Periodontology and Endodontology, Tohoku University Graduate School of Dentistry,
Sendai, Miyagi, Japan

Implantology Research
047: Salivary Alpha-Amylase as a stress marker during dental implant surgeries
A. A. Sabbagh, H. Nakata, A. Abdou, K. Shohei, S. Kuroda
Tokyo medical and Dental University, Tokyo, JAPAN

Oral Medicine & Pathology Research
048: Regional differences in the density of Langerhans cells, CD8-positive T lymphocytes
and CD68-positive macrophages
Y. OMINE
Iryouhoujin Syuuyuu-kai, Tsuchiura, Japan

Periodontal Research-Pathogenesis
049: Delayed Wound Healing after Tooth Extraction under Malnutrition

Y. ZHANG1, H. IDEGUCHI1, H. AOYAGI1, K. YAMASHIRO1, T. YAMAMOTO1, M. NISHIBORI2,
S. TAKASHIBA1
1
Department of Pathophysiology - Periodontal Science, Okayama University Graduate School of
Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan, 2Department of Pharmacology,
Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama,Japan

Oral & Maxillofacial Surgery Research
050: Assessment of Facial Changes after Orthognathic Surgery Using GeometricMorphometrics

S. AL BOUGHA1, H. NAKANO2, K. YASUDA1, T. YAMADA1, I. TAKAHASHI3, Y. MORI1
1
Section of Oral and Maxillofacial Surgery-Division of Maxillofacial Diagnostic and Surgical Science- Faculty of Dental Science, Kyushu University, 2Department of Dentistry and Oral Surgery, Divisionof Medicine for Function and Morphology of Sensory Organs, Faculty of Medicine, Osaka Medical
College, 3Department of Orthodontics, Faculty of Dental Science, Kyushu University

051: Metformin inhibits oral cancer cell growth by altering glucose metabolism

S. LIU1, J. WASHIO1, N. TAKAHASHI1
Division of Oral Ecology and Biochemistry, Department of Oral Biology, Tohoku University
Graduate School of Dentistry, Sendai, Japan, 2Department of Head and Neck Oncology, West China
Hospital of Stomatology Sichuan University, Chengdu, China

1

─ 18 ─

Oral Medicine & Pathology Research052: Sirtuin1 DNA hypermethylation may be a biomarker for malignant transformation
S. ISLAM, O. UEHARA, H. MATSUOKA, Y. ABIKO, I. CHIBA
Health Sciences University of Hokkaido

053: Role of EGFR-mediated MOB1 phosphorylation on Hippo pathway regulation
T. ANDO
Center of oral clinical examination, Hiroshima Univeresity Hospital, Hiroshima, Japan

054: Sema3A-AKT Axis In Salivary Gland And Adenoid Cystic Carcinoma Developments
T. FUJIMOTO1, S. FUJII2, T. KIYOSHIMA2
1
School of Dentistry, Kyushu University, 2Laboratory of Oral Pathology, Division of Maxillofacial
Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University

Oral & Maxillofacial Surgery Research
055: Effect of Ethinyl Estradiol on Mandibular Condyle of Female Rats

S. YAKLAI, R. PECHAYCO, Y. ABE, A. TAKIZAWA, I. MIZOGUCHI, T. TAKAHASHI, M.
CHIBA
Graduate School of Dentistry, Tohoku University

Craniofacial Biology Research
056: Histone methyltransferase SETDB1 negatively regulates PTH/PTHrP receptor inchondrocytes

P. THIHA, N. HIGASHIHORI, S. KANO, K. MORIYAMA
Department of Maxillofacial Orthognathics, Graduate School of Medical and Dental Sciences, Tokyo
Medical and Dental University

Stem Cell Biology Research
057: Generating MSC Spheroids Recovers Stemness Characteristics for Cortical Bone
Formation
Y. OHORI, K. NIIBE, H. EGUSADivision of Molecular and Regenerative Prosthodontics, Tohoku University Graduate School of
Dentistry, Sendai, Miyagi, Japan

Craniofacial Biology Research
058: The bHLH transcription factor HAND1 is involved in cortical bone volume throughthe regulation of collagen expression
N. FUNATO1, Y. TAGA3, L. E. LAURIE1, C. TOMETSUKA3, M. KUSUBATA3, K. OGAWAGOTO3
1
Department of Signal Gene Regulation, Tokyo Medical and Dental University, Tokyo, Japan,
2
Research Core, Tokyo Medical and Dental University, Tokyo, Japan, 3Nippi Research Institute of
Biomatrix, Ibaraki, Japan─ 19 ─

Mineralized Tissue059: Oxygen tension-dependent expression of monocarboxylate transpoter-1 is aprerequisite event for oxidative death of chondrogenic ATDC5 cells induced byinterleukin-1β.

M. TANAKA1, Y. MIYAMOTO1, K. YOSHIMURA1, K. SASA1, K. IKEZAKI1,2, T. SHIROTA2, R.
KAMIJO1
1
Department of Biochemistry, Showa University School of Dentistry, Tokyo, Japan, 2Department ofOral and Maxillofacial Surgery, Showa University School of Dentistry, Tokyo, Japan

Pediatric Oral Health Research
060: Effects of Anticancer Drugs on Mouse Tooth Germ Development

Y. TSUNODA1, S. NAKA1, R. OKAWA2, K. NAKANO2, M. MATSUMOTO-NAKANO1
Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry andPharmaceutical Sciences, Japan, 2Department of Pediatric Dentistry, Division of Oral Infection and
Disease Control, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan
1

Mineralized Tissue061: Trehalose, a natural sweetening compound, suppresses osteoclast differentiation.
S. NEGISHI, K. YOSHIMURA, R. KAMIJO
Department of Biochemistry, Showa University School of Dentistry062: Computational chemistry of phospholipid mineralization

E. S. HARA1, N. KUNIOSHI2, M. OKADA1, T. MATSUMOTO1
1
Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry andPharmaceutical Sciences, 2Department of Materials Science, Graduate School of Fundamental Scienceand Engineering, Waseda University, Tokyo, Japan

063: Histological study of dentin bridge formed beneath MTA after pulpotomies in rat
molarsA. TANAKA, T. TANASE, K. KOJIMA, H. HOMMA, A. SAKURAI, S. SHINTANI
Department of Pediatric Dentistry, Tokyo Dental College, Tokyo, Japan

Implantology Research064: The effect of micro-sized titanium on osteoblast differentiation

N. OMORI, H. NAKATA, S. KURODA
Department of Oral Implantology and Regenerative Dental Medicine, Division of Oral Health
Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University

Dental Materials 5: Biocompatibility, Bioengineering and Biologic Effects of Materials
065: Comparison in physical properties of synthetic carbonate apatite and allogeneic bone
graft substitute
N. KIMURA, S. KATO, E. ARIMA, N. KITAMURA, K. YAMANAKA, F. FUSEJIMAGC Corporation, Tokyo, Japan

066: Novel bio-active adhesive monomer CMET stimulates human dental pulp stem cells
differentiation toward odontoblast phenotype: a comparative study
Y.J. QIU, T. SAITO

─ 20 ─

Division of Clinical Cariology and Endodontology, Department of Oral Rehabilitation, Health
Sciences University of Hokkaido, Hokkaido, Japan

067: Hydrogel-based biomechanical environment for understanding Meckel's cartilage
fate
M. FARAHAT1, G. A. S. KAZI2, E.S. HARA1, T. MATSUMOTO1
1
Department of Biomaterials, Okayama University, Okayama, Japan, 2Department of Applied Life
Systems Engineering, Graduate School of Science and Engineering, Yamagata University

Diagnostic Sciences
068: Evaluation of Interleukin – 8 In Human Dental Pulp

S. TALWAR1, R.R. NAWAL1, A. KAUSHIK1, R. KONER2
1
CONSERVATIVE DENTISTRY AND ENDODONTICS, MAULANA AZAD INSTITUTE OFDENTAL SCIENCES, New Delhi, DELHI, INDIA, 2BIOCHEMISTRY, MAULANA AZADMEDICAL COLLEGE, NEW DELHI, DELHI, INDIA

Pulp Biology & Regeneration Research069: Interaction analysis of protein S100A7 in dental pulp tissue

M. WATANABE, M. OKAMOTO, H. HAILING, S. MATSUMOTO, K. MORIYAMA, Y.
TAKAHASHI, M. HAYASHI
dentistry, Osaka University, Suita, Japan

070: Lyve-1+ Pulpal Macrophages: M2-polarization and Response to Cavity Preparation

K. THOAI, K. TAZAWA, K. NARA, M. FUJII, K. HASHIMOTO, S. NODA, N. KAWASHIMA, T.
OKIJI
Department of Pulp Biology and Endodontics, Tokyo Medical and Dental University, Tokyo, Japan

071: DNA methylation of GJA1, BMP2 and BMP4 in a human cementoblast cell line
induced by lipopolysaccharide.

T. MURAMATSU1, F. KOBAYASHI2, O. UEHARA3, C. ITO4, M. FURUSAWA2, Y. ABIKO5
1
Department of Operative Dentistry, Cariology and Pulp Biology, Tokyo Dental College, Tokyo,
Japan, 2Department of Endodontics, Tokyo Dental College, Tokyo, Japan, 3Department of Oral Growthand Development, Health Sciences University of Hokkaido, Tobetsu, Japan., 4Oral Health Science
Center, Tokyo Dental College, Tokyo, Japan., 5Department of Human Biology and Pathophysiology,
School of Dentistry, Health Sciences University of Hokkaido, Tobetsu, Japan.

072: Effects of Non-thermal atmospheric pressure plasma on human deciduous dental
pulp fibroblast-like cells

M. OKUNO1, K. HARADA2, S. AOKI1, S. KAWAI2, K. ARITA2
Department of Pediatric Dentistry, Graduate School of Dentistry, Osaka Dental University, Osaka,
Japan, 2Department of Pediatric Dentistry, School of Dentistry, Osaka Dental University, Osaka, Japan1

Dental Materials 5: Biocompatibility, Bioengineering and Biologic Effects of Materials
073: Effect of Lithium Carbonate on the Healing of Apical Periodontitis

T. KAGIOKA, S. ITOH, H. NARUSE, Y. ITO, M. HAYASHI
Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of
Dentistry, Suita, Japan─ 21 ─

Pulp Biology & Regeneration Research
074: Large-conductance Ca2+-activated K+ Channels in Human Cementoblasts
S. KAMATA, M. KIMURA, Y. SHIBUKAWA, S. YAMASHITATokyo Dental College

075: Activation of CGRP receptors increased intracellular cAMP level in odontoblasts

N. SAITO, M. KIMURA, H. MOCHIZUKI, K. KOUNO, M. ANDO, S. OHYAMA, T. ICHINOHE, Y.
SHIBUKAWA
Tokyo Dental College, Tokyo, Japan

076: Plasma membrane Ca2+-ATPase regulates dentin formation and mineralization.
H. MOCHIZUKI, M. KIMURA, S. OHYAMA, K. KOUNO, M. ANDO, Y. SHIBUKAWA
Tokyo Dental College

Microbiology/Immunology
077: Functional expression of mechanosensitive ion channel in mouse osteoblasts

S. NAGAI1, K. KITAMURA3, M. KIMURA2, Y. SHIBUKAWA2, H. YAMAMOTO3, A.
KATAKURA1
1
Department of Oral Pathobiological Science and surgery, Tokyo Dental College, Tokyo, Japan,
2
Department of Physiology, Tokyo Dental College, Tokyo, Japan, 3Department of Histology andDevelopmental Biology, Tokyo Dental College, Tokyo, Japan

Pharmacology/Therapeutics/Toxicology
078: Activation of mechano-sensitive ion channels in cancer cells establishes paracrine
network via endothelin signaling

M. ISHIZAKI1, M. MATSUNAGA1, T. YAZAKI1, N. SAITOH1, S. OHYAMA2, M. KIMURA2, Y.
SHIBUKAWA2, T. ICHINOHE1
1
Department of Dental Anesthesiology, Tokyo Dental College, Tokyo, Japan, 2Department of
Physiology, Tokyo Dental College, Tokyo, Japan

Neuroscience
079: Mechanical stimulation-induced intercellular communication in trigeminal ganglion
neurons
T. YAZAKI1, M. ISHIZAKI1, M. MATSUNAGA1, S. OHYAMA2, H. KURODA3, M. KIMURA2, Y.
SHIBUKAWA2, T. ICHINOHE1,2
1
Department of Dental anesthesiology, Tokyo Dental Colledge, Tokyo, Japan, 2Department of
Physiology, Tokyo Dental Colledge, Tokyo Japan, 3Graduate School of Dentistly Department of
Critical Care Medicine and Dentistly, Kanagawa Dental University, Kanagawa Japan

080: Piezo1 channel activation evokes mechanosensitive Ca2+ signaling in humanodontoblast
M. MATSUNAGA1, M. KIMURA2, M. ISHIZAKI1,2, T. YAZAKI1,2, S. OHYAMA2, Y.
SHIBUKAWA2, T. ICHINOHE1
1
Dental Anesthesia, Tokyo Dental College, 2Physiology, Tokyo Dental College

─ 22 ─

Oral & Maxillofacial Surgery Research
081: Effects of preemptive analgesia with intravenous acetaminophen on postoperat ive
pain relief in patients undergoing third molar surgery: a prospective, single-blind,randomized controlled trial
K. KANO1,2, K. KAWAMURA3, T. MIYAKE3
1
Graduate School of Dentistry, Osaka Dental University, Osaka, Japan, 2Department of Dentistry
and Oral Surgery, Uji Takeda Hospital, Kyoto, Japan, 3Department of Preventive and Community
Dentistry, Osaka Dental University, Osaka, Japan

Diagnostic Sciences
082: Diagnostic and Prognostic Applications of Artificial Intelligence-based Radiology in
Head and Neck Region
M. Poorsattar1, A. Poursattar Bejehmir2
1
Private section, San Antonio, Texas, UNITED STATES, 2Private Section, Toronto, Ontario,
CANADAe-Oral Health Network
083: Revolutionalized Concept of Digitalizing Dental Treatment Contents using Machine
Learning

S. OKA1, K. NOZAKI2, M. HAYASHI1
1
Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of
Dentistry, Osaka, Japan, 2Division for Medical Information, Osaka University Dental Hospital, Osaka,
Japan

Education Research
084: Evaluation of simulation training courses on basic clinical skills for geriatricdentistry for trainee dentists

H. TAKETA1, T. YOSHIDA2, A. YABE1, N. SHIOTSU1, T. KONO1, H. SHIRAI1, Y. TORII1
1
Comprehensive Dental Clinic, Okayama University Hospital, Okayama, Japan., 2Center for
Education in Medicine and Health Sciences (Dental Education), Okayama University, Okayama,
Japan.

Behavioral, Epidemiologic and Health Services Research
085: Needs Of Dentists During The Covid-19 Pandemic In Nepal

Y. HARADA1, D. PRAJAPATI2, H. IWASHITA1, T. SUGISHITA1
1
International Affairs and Tropical Medicine, Tokyo Women's Medical University, 2Community andPublic Health Dentistry, Dhulikhel Hospital, Kathmandu University School of Medical Science

086: Oral conditions matter for general health of community-dwelling elderly population
Y. NAKAI1, Y. NAGATANI1, M. OZAKI2, K. OHUCHI2, H. KINOSHITA2, A. HIRANO2, T.
YANAGAWA2
1
Department of Dental Hygiene, University of Shizuoka Junior College, Shizuoka, Japan, 2Shizuoka
Dental Association, Shizuoka, Japan─ 23 ─

Oral Health Research
087: Comparative study of plaque removal effect on Japanese commercial toothbrushes.
C. HSU, K. SHINADA
Department of Preventive Oral Health Care Sciences, Tokyo Medical and Dental University, Tokyo,
Japan

088: Comparing the oral health-related quality of life of people with diabetes and people
without diabetes at a Tertiary Hospital in Nigeria
N. A. Ilochonwu
Preventive Dentistry, University of Port Harcourt, Choba, Port Harcourt, Rivers State, NIGERIA

Prosthodontics Research089: Survey Of Smile Satisfaction And Desired Treatments Among Medical And Dental
Students.

T. Khatri1, S. Butt2, A. Tufail1, R. Fatima1, Z. Irfan1
1
University of Health Sciences, Karachi, Sindh, PAKISTAN, 2University, Karachi, Sindh, PAKISTAN─ 24 ─

KEYNOTE LECTURE─ 25 ─

Keynote Lecture
Video On-demand distribution

KL
Porphyromonas gingivalis interactions with epithelial
cells in the community context

Richard J. Lamont, Ph. D.
Department Oral Immunology & Infectious Diseases, University of Louisville,
School of Dentistry

Oral epithelial cells are central to the maintenance of homeostasis in the face of adiverse and abundant microbial challenge. Bacteria with pathogenic potential, such as
Porphyromonas gingivalis, induce dysbiotic responses in oral epithelial cells which form
the basis for diseases such as periodontitis and, as is becoming increasingly recognized,
oral squamous cell carcinoma (OSCC). Virulence of P. gingivalis, however, is expressedin the context of heterotypic microbial communities which are comprised
predominantly of organisms generally considered commensal, such as the oral
streptococci. A major unanswered question therefore, is the extent to which organismsthat are commensal in an individual context can potentiate or mitigate pathogenicity
when in combination with P. gingivalis. We have used RNA-Seq to define gingival
epithelial cell pathways regulated in response to P. gingivalis alone, but restored toward
homeostasis by S. gordonii. Such pathways included those involved in proliferation,
migration, epithelial mesenchymal transition (EMT), apoptosis, and inflammation; andmany of these events revolved around the FOXO1-ZEB2 signaling axis. P. gingivalis
activated and increased nuclear retention of FOXO1 by dephosphorylation of serine
residues, and FOXO1 in turn controlled the production of anti-apoptotic factors such as
Bcl-6, and inflammatory mediators including several CXCL family chemokines. FOXO1
also bound to the promoter region of the ZEB2 gene and increased transcriptional
activity. Enhanced production of ZEB2 induced a partial EMT and stimulated themigration of gingival epithelial cells. In the presence of S. gordonii, however, there wasphosphorylation and activation of the TAK1-NLK pathway. Activated NLK was capableof phosphorylating FOXO1, and thus suppressed activation by P. gingivalis. Consistent
with this, S. gordonii prevented P. gingivalis from enhancing epithelial cell migration,
proliferation, EMT, resistance to apoptosis and production of inflammatory mediators.
The results suggest that on epithelial surfaces a relative decrease in the proportion of S.
gordonii to P. gingivalis would promote phonotypes which are hallmarks of cancer.
Conversely, an increase in the relative abundance of S. gordonii will inhibit the FOXO1ZEB2 regulatory axis and disrupt host responses in periodontal tissues.

─ 26 ─

GreetingSpecial Lecture

Professor Richard Lamont graduated with a BSc (Honours) from the University of Edinburgh in
1982 and completed his PhD in Bacteriology from the University of Aberdeen in 1985. He has
held academic appointments in various universities in the USA, and currently holds an
Endowed Professor and Chair in the Department of Oral Immunology and Infectious diseases
at the University of Louisville. He is also a recipient of various awards among which are IADRDistinguished Scientist Awards (1995, 2006), the MERIT award from NIH, and the University ofLouisville President’s Award for distinguished research (2016). He is a prolific researcher andis currently a principal investigator on 5 grants from NIH, and also an investigator or mentor
in 3 other active grants. He has authored over 200 publications in peer-reviewed journals and5 books. He has been editor in chief of the journal Molecular Oral Microbiology since 2015.

Keynote Lecture

Brief CV

Symposium I
Symposium II
Symposium III
Rising Scientist Session
Poster Presentation

─ 27 ─GREETING─ 29 ─

Greeting from IADR President
Video On-demand distribution

G

Pamela Den Besten, D.D.S., Ph. D
Professor in the Department of Orofacial Sciences, School of Dentistry,
University of California San Francisco

Pamela Den Besten is Professor in the Department of Orofacial Sciences, School of
Dentistry, University of California San Francisco. She directs the Center for Children’s
Oral Health Research, and co-directs the DDS-PhD and PhD programs in Oral and
Craniofacial Sciences within the School of Dentistry and the Graduate Division. Dr. Den
Besten is President of the International Association for Dental Research (IADR). She ispast Chair of the American Association for the Advancement of Science (AAAS) Section
on Dentistry & Oral Health Sciences. In 2009 Dr. Den Besten received the IADRDistinguished Scientist Award in Pulp Biology and Regeneration. She is an AAAS
honorary Fellow. Dr. Den Besten has published over 125 scientific manuscripts in peerreviewed journals, along with 18 book chapters. Her research interests are focused on
tooth formation, and in par ticular enamel and dentin regeneration andbiomineralization. She is an international leader in enamel fluorosis research, andstudies environmental effects on tooth formation.

─ 30 ─

Keynote Lecture

Greeting

Special Lecture

Symposium I

Symposium II

Symposium III

Rising Scientist Session

Poster Presentation

─ 31 ─

SPECIAL LECTURE─ 33 ─

Special Lecture
Video On-demand distribution

SL
Tubular Dentin Regeneration and Its Clinical Application

Joo-Cheol Park, D.D.S., Ph. D
Laboratory for the Study of Regenerative Dental Medicine,
Department of Oral Histology-Developmental Biology,
School of Dentistry, Seoul National University, Seoul, Korea

A healthy tooth is composed of nearly 70% dentin enclosing the entire dental pulp,
which is a pool of diverse stem cells. Loss of dentin not only generates unpleasant pain
but also ultimately leads to the weakening of whole tooth stability due to reduced
dentin thickness. Regenerative dental medicine has rapidly progressed since theadvancement of stem cell biology and material science. However, more emphasis has
been placed on the success of tissue formation than on how well the newly generated
tissue retains the original organ structure and function. Based on the knowledge thatepithelial-mesenchymal interaction is essential for tooth development, we previously
discovered a dental epithelium-derived protein called Copine 7 (CPNE7). CPNE7 is anevolutionarily conserved, calcium-dependent phospholipid-binding protein and consistsof two C2 domains in the N terminus and a von Willebrand factor A domain in the C
terminus. Secreted from pre-ameloblasts, CPNE7 induces odontoblast differentiation invitro and promotes dentin formation ex vivo. As a result, CPNE7 was suggested as a newmolecule with the potential to diffuse across the dentin and induce tertiary
dentinogenesis. The fact that recombinant CPNE7 is a cell-derived soluble bioactive
molecule makes it a promising candidate for use in regenerative dental medicine.
Moreover, a synthetic CPNE7-derived oligopeptide, Cpne7-DP, was developed which
induces odontoblast differentiation in vitro and physiologic dentin formation in vivo.
Comprehensive evaluation of Cpne7-DP further validated its potential as a bioactive
therapeutic agent. Our results suggest that the dual functions of Cpne7-DP in tubular
dentin formation and peritubular space occlusion are promising for oral diseasetargeted application, especially those involving dentinal loss and sensitivity.

─ 34 ─

Keynote Lecture

Brief CV
Name:
Joo-Cheol Park

Citizenship: Korean
Education and Training:
1981.03-1987.02 D. D. S.
Chosun University, College of Dentistry, Kwang-ju, Korea

Special Lecture

Address:
1, Gwanak-Ro, Gwanak-Gu, Seoul, #08826
Republic of Korea
Tel: +82-2-880-2335
Fax: +82-2-878-2338
E-mail:jcapark@snu.ac.kr
Laboratory Website: toothbiology.prof-lab.net

Greeting

Appointment:
Professor
Laboratory for the study of Regenerative Dental medicine, Department of Oral Histology-Developmental Biology,
Seoul National University

1987.09-1989.08 M. S.
Chosun University, Graduate School, Kwang-ju, Korea

1994.03-1996.08 Doctoral Course (equivalent to Ph. D., Oral Anatomy)
Seoul National University, Graduate School, Seoul, Korea

(1)
(2)
(3)
(4)

Control of odontoblast differentiation and dentin formation
Nuclear factor I-C and mineralized tissue homeostasis
A periodontitis biomarker, ODAM and junctional epithelium
Dental stem cells and periodontal regeneration

Poster Presentation

─ 35 ─

Rising Scientist Session

References
Park YH, Lee YS, Seo YM, Seo H, Park JS, Bae HS, Park JC. Midkine promotes odontoblast-like differentiation and tertiary dentin
formation. J Dent Res. 99(9):1082-1-91, 2020.
Park SH, Lee YS, Lee DS, Park JC, Kim R, Shon WJ. CPNE7 induces biological dentin sealing in a dentin hypersensitivity model. J
Dent Res. 98(11), 1239-1244, 2019.
Seo YM, Park SJ, Lee HK, Park JC. Copine-7 binds to the cell surface receptor, nucleolin, and regulates ciliogenesis and Dspp
expression during odontoblast differentiation. Sci Rep. 7(1):11283, 2017.
Choung HW, Lee J-H, Shon WJ, Lee JH, Y. Ku, Park JC. Tertiary dentin formation after indirect pulp capping using protein CPNE7.
J Dent Res. 95(8):906-912, 2016.
Oh HJ, Choung HW, Lee HK, Park SJ, Lee JH, Lee DS, Seo BM, Park JC. CPNE7, a preameloblast-derived factor, regulatesodontoblastic differentiation of mesenchymal stem cells. Biomaterials 37:208-217, 2015.
Lee JH, Lee DS, Choung HW, Shon WJ, Seo BM, Lee EH, Cho JY, Park JC. Odontogenic differentiation of human dental pulp stem
cells induced by preameloblast-derived factors. Biomaterials 32(36):9696-9706, 2011.

Symposium III

Major Research Interest:

Symposium II

Academic Appointments and Career:
1990.02-1993.04 Military service in Korean Army
1997.02-1999.01 Postdoctoral research Fellow (supported by Tokyo Biochemical Research Foundation), Department ofBiochemistry & Molecular Biology, Okayama Medical School, Okayama, Japan
1995.05-2007.07 Instructor, Assistant professor, Associate professor and Professor, Department of Oral Histology, Collegeof Dentistry, Chosun University. Gwang-ju, Korea
2003.06-2004.08 Research Associate Professor, Department of Oral Biology, SUNY at Buffalo, NY, USA
2013.01- 2014.12 Associate Dean for Research affairs, School of Dentistry,Seoul National University. Seoul, Korea
2017.02-2019.02 Director, Dental Research Institute, Seoul National University
2007.08Associate professor and Professor, Department of Oral Histology-Developmental Biology, School of
Dentistry,Seoul National University. Seoul, Korea
2016.07Founder & CEO, HysensBio Co., Ltd.
2020.10President of KADR

Symposium I

1987.03-1990.02 Internship and Residency (Oral Pathology)
Chosun University, College of Dentistry, Kwang-ju, Korea

SYMPOSIUM
Symposium I :At the front-line: Etiology of periodontitis

Symposium II:
Future is now! Stem cell revolution in hard and soft tissue
engineering

Symposium III:
Pathophysiological approach from oral function to systemic
diseases

Rising Scientist Session
Neuroscience─ 37 ─

Symposium I
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 7 (Sat.) 10:20-10:30
SI-1
Bacterial composition of overall oral microbiota
associated with periodontal disease and health.

Toru Takeshita, D.D.S., Ph. D
Section of Preventive and Public Health Dentistry, Faculty of Dental Science,
Kyushu University

Oral cavity is colonized by numerous and diverse commensal microorganisms, whichconstitute complex microbial communities on various intraoral surfaces. Of them,plaque microbiota that forms on the tooth surfaces and gingival crevices are the causeof one of two major oral diseases, or periodontitis. Currently, little doubt exists thatthree subgingival plaque bacteria including Porphyromonas gingivalis, Tannerella
forsythia and Treponema denticola are prime suspects in periodontitis. Furthermore,
recent studies using open-ended molecular approaches and the 16S rRNA gene haveidentified additional species, including Filifactor alosis as the periodontitis-associatedtaxa. Nevertheless, the bacterial etiology of periodontitis remains unclear, because theonset and progression of periodontitis cannot be simply explained by presence orabsence of these taxa.
To obtain deeper insights into oral microbiota composition associated with periodontal
disease and health, we conducted a large-scale population-based study of oral
microbiota composition using saliva. An important finding was that high bacterial
richness in the microbiota constituted by various minority bacteria mainly derived from
subgingival sites was significantly associated with gingival inflammation andperiodontitis. Another important result was that relative abundances of predominantcommensals were significantly associated with the health conditions. Of the twodifferent cohabiting groups of predominant commensals mainly derived from tongue
dorsum, a greater relative abundance of group II bacteria such as Neisseria flavescens
and Porphyromonas pasteri, and Fusobacterium periodonticum was associated with
better health conditions. We introduce our finding on the overall structure of the oral
microbiota associated with gingival health obtained by our molecular epidemiologicalstudies.

─ 38 ─

Toru Takeshita
Section of Preventive and Public Health Dentistry, Faculty of Dental Science, Kyushu University

Award
2014 Japanese Society of Oral Health “LION AWARD”

Special Lecture

Research Appointment
2007-2009
JSPS Research Fellowship for Young Scientists
2009-2013
Assistant Professor, Kyushu University
2013-current Associate Professor, Kyushu University

Greeting

Education
Undergraduate 1999-2005 Kyushu University, Faculty of Dentistry, D.D.S.
Graduate 2005-2009 Kyushu University Graduate School of Dental Science, Ph.D.

Keynote Lecture

Brief CV

Symposium I
Symposium II
Symposium III
Rising Scientist Session
Poster Presentation

─ 39 ─

Symposium I
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 7 (Sat.) 10:50-11:00
SI-2
The significant role of Porphyromonas gingivalis“Gingipains” as a virulence factor on periodontal
inflammation
Masaaki Nakayama, Ph. D, Naoya Ohara
1) Department of Microbiology, Graduate school of Medicine, Dentistry andPharmaceutical Sciences, Okayama University, and Advanced Research Center
for Oral and Craniofacial Sciences (ARCOCS), Dental School, Okayama Universityl

Periodontal disease is an infectious and inflammatory disease in periodontal tissues,and is also considered to link with systemic diseases such as diabetes, vascular andcardiovascular diseases. Porphyromonas gingivalis is well known as one of high-risk
pathogens, and its persistent infection may contribute to the destruction of periodontal
tissues, eventually also affect the systemic diseases. Periodontal disease has
proinflammatory mediators including interleukin-6, TNFα, and prostaglandins (PGs). In
our recent research, we have focused on the function of cysteine proteases “gingipains”,
which are the virulence factors from P. gingivalis. and studied the relationship between
gingipains and PGE2 production in P. gingivalis infection. In this study, humanmonocytes were challenged with wild-type P. gingivalis (wtPg) and gingipains-deficientmutant strain (mtPg) to investigate molecular characterizations of the cellular signaling
caused by the host cell-pathogen interactions. We found that gingipains induced COX-2
expression and PGE2 production via activation of MEK/ERK/AP-1 (c-fos/c-Jun) and IKK/
NF-κBp65, and their proteolytic activity is crucial to cause these events. Furthermore,
we examined the upstream pathways leading to MEK/ERK/AP-1 and IKK/NF-κBp65, andthen found the involvement of calcium influx and activation of TLR4 signaling in
gingipains-induced signaling pathways for COX-2 expression. It is likely that COX-2
expression/PGE2 production induced by gingipains has several interactions and signaling
pathways in the monocytes infected with P. gingivalis. Taken together, our study
provides the significant role of P. gingivalis gingipains in periodontal inflammation.

─ 40 ─

Masaaki Nakayama
Department of Microbiology, Graduate school of Medicine, Dentistry and Pharmaceutical
Sciences, Okayama University

Greeting

Education:
Undergraduate 1996-2000 Nagasaki University, B.S.
Postgraduate 2000-2002 Nagasaki University, M.S.
Graduate 2002-2006 Nagasaki University, Ph.D.

Keynote Lecture

Brief CV

Research Appointment
2007-2008
Post-doctral fellow, The Institute of Tropical Medicine, Nagasaki University
2008-2010
Post-doctral fellow, National University of Singapore, Cancer Science Instituteof Singapore, Singapore
2010-current Assistant professor, Graduate school of Medicine, Dentistry and Pharmaceutical
Sciences, Okayama University

Special LectureAwards
2015
2016
2016

Symposium I

The 35th Ryobi Teien Memory Fundation Award
The 58th Japanese Association for Oral Biology, Rising Members AwardThe 69th Japanese Society for Bacteriology, Chugoku-Shikoku branch, Young
Researcher Encouraging Award

Symposium II
Symposium III
Rising Scientist Session
Poster Presentation

─ 41 ─

Symposium I
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 7 (Sat.) 11:20-11:30
SI-3
Title: Periodontitis as an “osteoimmune” disease

Masayuki Tsukasaki, D.D.S., Ph. D.
Department of Immunology, Graduate School of Medicine and Faculty of
Medicine, The University of Tokyo

Periodontitis, one of the most common infectious diseases in humans, is a unique“osteoimmune” disease in which antibacterial immune response causes alveolar bone
destruction. In 1972, Horton et al. reported that immune cells stimulated by the dental
plaque derived from periodontitis patients produce osteoclast-activating factors,
providing the first evidence for the osteoimmune dialogue (Horton et al., Science 1972).
However, although the pioneering work in the field of osteoimmunology was conductedin the context of periodontitis, the mechanisms and the role of osteoimmune
interaction in periodontitis have been largely unclear until fairly recently.
Using a newly established murine periodontitis model, we showed that the crosstalk
between immune and bone cells at the oral barrier plays a critical role in thepathogenesis of periodontitis. Bacterial invasion leads to the generation of specialized
immune cells that protect against bacteria by evoking mucosal immune responses aswell as inducing bone damage, the latter of which may also contribute to the hostdefense by removing the infected-tooth. These findings suggest that inflammatory bone
destruction, which has been regarded merely as an adverse secondary effect ofinflammation, may have evolved as a part of host defense machinery against oral
microbiota (Tsukasaki et al., Nature Commun 2018, Nature Rev Immunol 2019).
To understand the pathogenesis of and develop future therapeutic strategies forperiodontal bone loss, it is vitally important to clarify precise molecular mechanisms
underlying osteoclastic bone erosion. Recently, we unveiled the importance of the tightregulation of RANKL activity by the local OPG production in bone and immune systems
by generating OPG-floxed mice (Tsukasaki et al., Cell Rep in press), and deciphered the
stepwise cell fate decision pathways during osteoclastogenesis at single-cell resolution(Tsukasaki et al., Nature Metabolism in revision). In this talk, I will summarize the recent
progress of the osteoimmunology field and provide a new perspective on the
periodontology from the osteoimmunological standpoint.

─ 42 ─

Masayuki Tsukasaki
Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The
University of Tokyo

Graduated from the Showa University School of Dentistry, D.D.S.
Graduated from the Graduate School of Medicine, the University of Tokyo,
Ph.D

2019

2019
2018
2018

2016

2013
2012

Rising Scientist Session

2016
2016

Symposium III

2017
2017

Symposium II

2019
2019
2019

The Japanese Society for Bone and Mineral Research, Rising Stars Grant
The 5th Winter seminar of Japanese Society of Ostoimmunology, Best researchaward
The Japanese Society for Bone and Mineral Research, 4th Skeletal Science
Retreat, Best discussion award
Japanese Association for Oral Biology, Young investigator award
The Oral Medical Science Frontier, Young investigator award
The 47 th Annual Meeting of the Japanese Society for Immunology, Best
presentation award
The 4th Winter seminar of Japanese Society of Ostoimmunology, Best researchaward
7th International Conference on Osteoimmunology Travel Award
Japanese Society for Immunology, Tadamitsu Kishimoto International TravelAward
The Advanced Dentistry School, Best research award
The 2nd Winter seminar of Japanese Society of Ostoimmunology, Best researchaward
The Thailand International Conference on Oral Biology (TICOB) 2016, Best
presentation award
6th International Conference on Osteoimmunology, Travel Award
The 1st Winter seminar of Japanese Society of Ostoimmunology, Best researchaward
Showa University, Kamijo PrizeJapan Student Services Organization (JASSO), Student of the Year, First Prize

Symposium I

Awards2020
2020

Special Lecture

Research Appointment
2014-2018
Graduate Program for Leaders in Life Innovation (GPLLI), the University ofTokyo
2015-2018
Research Fellow of the Japan Society for the Promotion of Science (DC1)
2018Research Fellow of the Japan Society for the Promotion of Science (PD)Greeting

Education
2013
2018

Keynote Lecture

Brief CV

Poster Presentation

─ 43 ─

Symposium I
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 7 (Sat.) 11:50-12:00
SI-4
Epithelial barrier breakdown by Porphyromonas
gingivalis

Atsuo Amano, D.D.S., Ph. D. and Hiroki Takeuchi
Department of Preventive Dentistry, Graduate School of Dentistry, Osaka
University

Porphyromonas gingivalis is one of keystone pathogens in severe and chronic
manifestations of periodontal diseases. A central feature of P. gingivalis pathogenicity isdysregulation of innate immunity at the gingival epithelial interface; however, themolecular basis underlying P. gingivalis–dependent abrogation of epithelial barrier
function remains unknown. Gingival epithelial cells express junctional adhesion
molecule (JAM1), a tight junction–associated protein, and JAM1 homodimers regulate
epithelial barrier function. We showed that Arg-specific or Lys-specific cysteine
proteases (gingipains) secreted by P. gingivalis specifically degraded JAM1 at K134 andR234 in gingival epithelial cells, resulting in permeability of the gingival epithelium to 40
kDa dextran, lipopolysaccharide (LPS), and proteoglycan (PGN). A P. gingivalis strain
lacking gingipains was impaired in degradation of JAM1.
Next, we employed a three-dimensional (3D) multilayered tissue model using epithelial
cells coated with fibronectin/gelatin nano-films. Knockdown of JAM1 in monolayer cells
and 3D multilayered tissue model also increased permeability to LPS, PGN, andgingipains. Inversely, overexpression of JAM1 in epithelial cells prevented penetrationby these agents following P. gingivalis infection. Our findings strongly suggest that P.
gingivalis gingipains disrupt barrier function of stratified squamous epithelium via
degradation of JAM1, allowing bacterial virulence factors to penetrate into subepithelial
tissues.
If circumstances warrant, we may be able to show the data indicating that P. gingivalis
breaks through the epithelial barrier using an intercellular, rather than intracellular,
pathway to get into the deeper tissues.

─ 44 ─

Atsuo Amano, D.D.S., Ph.D.
Professor and Chair
Department of Preventive Dentistry, Graduate School of Dentistry, Osaka University

Symposium II

Yumikura Award in Dental Research of Osaka University
Lion Science Award of Japanese Society of Periodontology
President Award of Osaka University

Symposium I

Honors
1998
2001
2015

Special Lecture

Professional Career2015 - 2018 Dean, Graduate School of Dentistry and School of Dentistry, Osaka University
2011 - Present Professor and Chair, Department of Preventive Dentistry, Graduate School of
Dentistry, Osaka University
2000 - 2011 Professor and Chair, Department of Oral Frontier Biology, Graduate School of
Dentistry, Osaka University
1997 - 2000
Associate Professor, Division of Special
Care Dentistry, Osaka University Dental Hospital
1992 - 1994
Postdoctoral fellow, Department ofOral Biology, School of Dental Medicine, State University of New York at
Buffalo
1987 - 1997 Assistant Professor, Department of Preventive Dentistry, School of Dentistry,
Osaka University

Greeting

Education and Degree
1984
D.D.S., School of Dentistry, Osaka University
1990
Ph.D., Graduate School of Dentistry, Osaka University

Keynote Lecture

Brief CV

Symposium III
Rising Scientist Session
Poster Presentation

─ 45 ─

Symposium II
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 8 (Sun.) 10:20-10:30
SII-1
Generation of skeletal cells from pluripotent stem cells

Shinsuke Ohba, D.D.S., Ph. D.
Department of Cell Biology, Institute of Biomedical Sciences, Nagasaki
University

Pluripotent stem cell (PSC)-based differentiation systems are a promising tool for invitro mechanistic studies of developmental processes, disease modeling, drug screening,and stem cell-based therapies. Recent understanding of signaling pathways regulating
developmental processes provides us with clues for appropriate inducers for PSC
differentiation. We have developed several strategies to generate skeletal cells frommouse and human PSCs under fully defined conditions (Stem Cell Reports, 2014; Sci Adv,
2017; Regen Ther, 2020), based on our previous findings on the Hedgehog signalingmediated specification of bone-forming cells (Development, 2008; Dev Cell, 2008; J Biol
Chem, 2012; J Biol Chem, 2013) and canonical Wnt signaling-directed control ofpluripotency and differentiation of PSCs (Stem Cells, 2013). Our strategies are basicallycomposed of three phases: maintenance of PSCs, induction of mesoderm and skeletal
progenitors, and differentiation of the progenitor population into skeletal cells.
Induction of mesoderm and skeletal progenitors is achieved in vitro under fully definedconditions, where activities of developmentally critical signals are manipulated by small
molecules. We have found that the PSC-derived progenitor cells give rise to osteogenic
and/or chondrogenic population under appropriate conditions. Thus, the strategies will
be a novel platform for biological and pathological studies of skeletal development,
screening of therapeutic drugs for the treatment of degenerative skeletal disorders, andregeneration of skeletal tissues.

─ 46 ─

Shinsuke Ohba
Department of Cell Biology, Institute of Biomedical Sciences, Nagasaki University

Ph.D., Graduate School of Medicine, University of Tokyo
D.D.S., School of Dentistry, Tohoku University

2017
2016
2011

2004
2004
2001

Symposium III

2005

Symposium II

2018

Invited Speaker, 2019 Gordon Research Conference Cartilage Biology andPathology
JSBMR Research Encouragement Award, Japan Society for Bone and Mineral
Research
Paper Award, Japanese Society of Cartilage Metabolism
ASBMR Rising Star Award, American Society for Bone and Mineral Research
Invited Speaker, 2011 Gordon Research Conference Cartilage Biology andPathology
Outstanding Paper Award, 23th Annual Meeting of Japan Society for Bone andMineral Research
Outstanding Paper Award, 22th Annual Meeting of Japan Society for Bone andMineral ResearchAward for Excellence, 6th Asian Congress on Oral and Maxillofacial Surgery
DENTSPLY Merit Award, DENTSPLY International Inc.

Symposium I

Awards2019

Special Lecture

Research and professional experience
2019Professor, Department of Cell Biology, Nagasaki University
2017-2019
Associate Professor, Department of Clinical Biotechnology, University of Tokyo
2013-2017
Project Associate Professor, Department of Bioengineering, University of Tokyo
2010-2013
Project Assistant Professor, Department of Clinical Biotechnology, University ofTokyo
2008-2010
Postdoctoral Fellow, Department of Molecular and Cellular Biology, Harvard
University
2005-2007
JSPS Research Fellow, Department of Tissue Engineering, University of Tokyo
Hospital
2002-2006
Graduate student, Graduate School of Medicine, University of Tokyo
2001-2002
Resident in Oral and Maxillofacial Surgery, University of Tokyo Hospital

Greeting

Education
2006
2001

Keynote Lecture

Brief CV

Rising Scientist Session
Poster Presentation

─ 47 ─

Symposium II
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 8 (Sun.) 10:50-11:00
SII-2
Establishment of an in vitro culture system fortenogenic/ligamentogenic differentiation using ScxGFP
iPS cells
Chisa Shukunami, D.D.S., Ph. D.
Department of Molecular Biology and Biochemistry, Graduate School of
Biomedical and Health Sciences, Hiroshima University

Tendons connect muscles to the skeletal components and function as the mechanicalforce transmitters, while ligaments bind adjacent bones together to stabilize joints. Cells
in tendons and ligaments are specialized fibroblasts known as tenocytes andligamentocytes. Tenocytes and ligamentocytes are derived from progenitor cells that
express the basic helix-loop-helix transcription factor Scleraxis (Scx). A certain
population of Scx+ cells also express Sry-box 9 (Sox9). These Scx+/Sox9+ cells differentiate
into tenocytes and ligamentocytes as well as chondrocytes that contribute to theformation of attachment sites of tendons/ligaments to bone, entheses. Loss of function
analysis of Scx revealed that Scx is required for maturation of tendons/ligaments andthe entheses. So far, little is known about the molecular mechanism underlying
tenogenic and ligamentogenic lineage commitment and differentiation due to a lack ofsuitable cell culture system. In this study, we established an in vitro culture system thatcan monitor tenocyte and ligamentocyte differentiation by live imaging using green
fluorescence. ScxGFP iPS cells were established from fibroblasts isolated from ScxGFP
transgenic mouse embryos that express EGFP in the Scx-expressing region during
development. We generated chimeric mice to confirm that ScxGFP iPS derived cells
express green fluorescence upon differentiation into the tenogenic and ligamentogenic
cells. We then explored the culture conditions for differentiation of ScxGFP iPS cells into
tendon/ligament cells monitoring GFP expression. Under optimal conditions, ScxGFP iPS
cells are differentiated into mesenchymal progenitor cells and then into Scx+ cells
expressing GFP. Scx+ cells mature to express tenomodulin and Mohawk at higher levels
than tenocytes isolated from limb tendons. Most of Scx+ cells express Sox9, but Sox9
expression in Scx+/Sox9+ cells decreased in association with tenocyte and ligamentocyte
differentiation. Thus, taking advantage of ScxGFP iPS cells, we have successfully
established the culture system that recapitulates the process of tendon and ligament
formation in vivo.

─ 48 ─

Chisa Shukunami, DDS, PhD
Department of Molecular Biology and Biochemistry, Graduate School of Biomedical and
Health Sciences, Hiroshima University

Undergraduate, Faculty of Dentistry, Hiroshima University
Graduate, Graduate School of Dentistry, Osaka University

2007

The 3rd Pan Pacific Connective Tissue Societies Symposium Young Investigator
Award
Otaka Award, Japanese Society for Matrix Biology and Medicine

Symposium I

Awards
1995

Special Lecture

Research Appointment
1994-1995
Japan Society for the Promotion of Science (JSPS) fellow (DC2)
1995-1998
JSPS fellow (PD)1998-2013
Associate Professor, Kyoto University
1999
Human Frontier Science Program short-term fellow,
GSF-National Research Center for Environment and Health, Germany
2013-current Professor, Hiroshima University

Greeting

Education
1985-1991
1991-1995

Keynote Lecture

Brief CV

Symposium II
Symposium III
Rising Scientist Session
Poster Presentation

─ 49 ─

Symposium II
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 8 (Sun.) 11:20-11:30
SII-3
Classification and pathological mechanisms of
Craniosynostosis based on the differentiation patternof iPS cells
Sachiko Iseki, D.D.S., Ph. D.
Section of Molecular Craniofacial Embryology, Tokyo Medical & Dental
University Graduate School of Medical and Dental Sciences

Craniosynostosis is defined as premature closure of one or more cranial sutures. It issuggested that the condition is induced by accelerated ossification leading tocraniofacial skeletal deformities and compromise of cranial space for growing brain.
Although it is a multifactorial disease with several risk factors including increased
intracranial pressure, the involvement of genetic factors is strongly suggested. The
current treatment is mainly surgical resection, and repeated surgeries are often
required due to resynostosis. Therefore, prediction of clinical condition is important fortreatment planning. However, currently reported gene mutations in craniosynostosis
patients explain only 20% of all craniosynostosis cases.
The ability to predict the pathological transition not only facilitates the planning oftreatment strategies but also the development of new therapies. Since it is currently
impossible to classify patients based on genetic factors alone, we hypothesized that theexpression pattern of osteogenic markers and craniosynostosis associated genes inosteobalsts could be used to classify craniosynostosis patients.
Cranial bone-derived osteoblast ossification capacity is known to change with age,
therefore It is not easy to compare the pattern of expression of osteogenic markers
among patient-derived osteoblasts and control osteoblasts directly.
It has been reported that iPS cells maintain an epigenetic state character from which
they are derived, therefore they are prone to easily differentiate into the original cell
type.
Using this feature, we will establish a system to establish patient osteoblast-derived iPS
cells and redifferentiate them into osteoblasts to compare the expression patterns ofosteogenic markers for patient classification.

─ 50 ─

Sachiko Iseki
Section of Molecular Craniofacial Embryology, Tokyo Medical & Dental University Graduate
School of Medical and Dental Sciences

Special Lecture
Symposium I
Symposium II
Symposium III

Research Appointment
Apr 1993
Research assistant, Department of Developmental
Biology, Tokyo Medical and Dental University, JapanMay 1993-Mar 1994
Research Associate, Department of Developmental
Biology, Tokyo Medical and Dental University, Japan
Apr 1994-Nov 1995
Research Associate, Department of Oral Pathology,
Tokushima University, Japan
Dec 1994-Nov 1996
HFSP Long-term Research Fellow, Department of
Human Anatomy, University of Oxford, United
Kingdom
Dec 1996-Mar 1997
Post-doctoral Research Assistant of Action
Research, Department of Developmental Biology,
Tokyo Medical and Dental University, Japan
Apr 1997-Mar 1999
Research Associate, Department of Developmental
Biology, Tokyo Medical and Dental University, Japan
Dec 1997-Mar 1999
Post-doctoral Research Assistant of Action
Research, Department of Human Anatomy,
University of Oxford, United Kingdom
Apr 1999-Dec 2007
Research Associate, Department of Molecular
Craniofacial Embryology, Graduate School, Tokyo
Medical and Dental University, JapanJan 2008Professor, Department of Molecular
Craniofacial Embryology, Graduate School, Tokyo
Medical and Dental University, Japan

Greeting

Educations
Undergraduate: 1983-1989 Tokyo Medical and Dental University, Faculty of Dentistry, D.D.S.
Graduate School: 1989-1993 Tokyo Medical and Dental University, Faculty of Dentistry, Ph. D

Keynote Lecture

Brief CV

Rising Scientist Session
Poster Presentation

─ 51 ─

Symposium II
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 8 (Sun.) 11:50-12:00
SII-4
Molecular mechanisms of craniosynostosis in Apert
syndrome.

Takashi Nakamura, Ph. D.
Department of Biochemistry/Research Branding Project, Tokyo Dental College.

Hiroyuki Ogura
Department of Orthodontics, Tokyo Dental College.

Toshifumi Azuma
Department of Biochemistry/Oral Health Science Center/Research Branding Project, Tokyo Dental
College.

Apert syndrome(AS) is an inherited disorder caused by FGFR2 gene mutations and ischaracterized by craniosynostosis and osseous syndactyly, associated with enhanced
osteoblast differentiation. However, no systemic excessive bone formation has been
observed in AS patients, and the mechanisms of site-specific osteoblast hyper activation
remains unclear. Here, we report that mechanical factors are related to the AS
pathogenesis. To elucidate the molecular mechanisms of osteoblast activation in AS, we
first established iPS cells from AS patients and analyzed osteoblast differentiation.
However, no clear abnormalities were observed in AS-iPS cell derived osteoblasts. Since
the bone abnormalities in AS are confined to cranial sutures and fingers, andmechanical stress causes craniofacial deformity in patients, we hypothesized thatmechanical stimulation may trigger site-specific hypercalcification. Mechanical stressloading on normal human mesenchymal stem cells (hMSCs) using cell stretching systemcaused increased FGF2 gene expression and enhanced proliferation, which was offset
by FGF2 neutralizing antibody. Furthermore, FGF2-dependent cell proliferation during
the early stages of osteoblast differentiation caused cell condensation, which promoted
subsequent osteoblast maturation and calcified nodule formation. This indicates that
FGF2 gene expression is important for the mechanical stress-dependent boneformation. The induction of osteoblast differentiation in AS-iPS cells under mechanicalstress showed increased calcification compared to wild-type iPS cells. Namely,
mechanical cues increased the local concentration of FGF2, which, in concert withmutant FGFR2, may induce excessive bone formation in AS. These results suggest thatthe mechanical stress response may be a new therapeutic target for AS.

─ 52 ─

Takashi Nakamura
Department of Biochemistry/Research Branding Project, Tokyo Dental College.

Symposium II

Young Investigator Award, American Society for Bone and Mineral Research
Encouragement Award, Japanese Society for Bone and Mineral Research
Plenary Poster Award, American Society for Bone and Mineral Research
JSBMR Poster Award, Japanese Society for Bone and Mineral Research
Excellent Presentation Award, Neo Vitamin D Workshop

Symposium I

Awards
2004
2005
2005
2014
2016

Special Lecture

Research Appointment
2005-2006
Postdoctoral fellow, IMCB, The University of Tokyo/ERATO, JST
2006-2007
Research/Teaching assistant, MRI, Tokyo Medical and Dental University
2007-2010
Assistant Professor, MRI, Tokyo Medical and Dental University
2010-2016
Assistant Professor, Keio University School of Medicine/ERATO, JST
2016-2017
Associate Professor, Keio University School of Medicine
2017-current Associate Professor, Tokyo Dental College

Greeting

Education
Undergraduate 1996-2000 Tokyo University of Agriculture, Department of Agricultural
Chemistry
Graduate 2000-2005 The University of Tokyo, Graduate School of Agricultural and Life
Sciences, Ph.D.

Keynote Lecture

Brief CV

Symposium III
Rising Scientist Session
Poster Presentation

─ 53 ─

Symposium II
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 8 (Sun.) 12:20-12:30
SII-5
Application of iPS cell technologies to treat skeletal
diseaseAkihiro Yamashita, D.D.S., Ph. D., Noriyuki Tsumaki
Centre for iPS cell Research and Application (CiRA), Kyoto University, JapanThe bone has two types of cartilage, articular cartilage and growth plate cartilage.
Articular cartilage covers the end of bone and provides lubrication to diarthrodial joints.
Trauma or degeneration of articular cartilage causes joint pain during motion, leading tothe onset of osteoarthritis. Growth plate cartilage, where the bone grows in children,and its dysfunction due to genetic mutations causes skeletal dysplasia. The conditions
that compromise articular cartilage or growth plate cartilage are poorly understood,
and curative drugs are not available. iPS cell technologies are being used to study theseskeletal diseases. We have been developing a method in which human iPS cells aredifferentiated into chondrocytes, the cells that constitute cartilage. We are generating
effective and safe human iPS cell-derived cartilage as regenerative medicine to treat
focal articular cartilage defects. We have confirmed their safeness and efficacy using
animal transplantation models. We have also generated iPS cells from patients with
FGFR3 chondrodysplasia. We found that chondrocytes derived from patient-iPS cells
produce abnormal cartilage formation and thus offer a unique cellular disease model. In
this seminar, we will introduce our projects to treat skeletal disease.

─ 54 ─

Akihiro YAMASHITA, D.D.S., Ph.D.
Department of Clinical Application, Center for iPS cell Research and Application (CiRA), Kyoto
University

2010
2011

2015
2016

Symposium II

2013
2015

AHFMR Postdoc Recruitment Award, Alberta Heritage Foundation for Medical
Research, Canada.
Excellent Postdoctoral Fellow Award, SACRI, U of Calgary, Canada
BMB Postdoctoral Fellow Award, Department of Biochemistry and molecularbiology, U of Calgary, Canada
Presentation Award, The Japanese Society of Inflammation and Regeneration,
Excellent Poster Award, 18 th Takeda Science Foundation Symposium on
Bioscience
Incentive Award, Japanese Society for Regenerative Medicine
Japanese Society for cartilage metabolism Award, 21th Japanese Society for
cartilage metabolism

Symposium I

Awards2006

Special Lecture

Research Appointment
2007-2011
Postdoctoral Fellow: University of Calgary, Department of Biochemistry &Molecular Biology, Canada
2012-2015
Postdoctoral Fellow: Kyoto University, Center for iPS Cell Research Application,Japan
2015-current Assistant Professor: Kyoto University, Center for iPS Cell Research Application,Japan

Greeting

Education
Undergraduate 1995-2001 Hiroshima University, Faculty of Dentistry, D.D.S.
Graduate 2003-2007 Shiga University of Medical Science, Graduate School of Medical
Science, Ph.D.

Keynote Lecture

Brief CV

Symposium III
Rising Scientist Session
Poster Presentation

─ 55 ─

Symposium III
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 8 (Sun.) 13:20-13:30
SIII-1
Taste renin-angiotensin system may contributeto the maintenance of sodium homeostasis.

Noriatsu Shigemura1,2), D.D.S., Ph. D.
1) Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu
University, 2) Research and Development Center for Five-Sense Devices, Kyushu
University.

Sodium ion (Na+) is the principal extracellular cation maintaining body fluid homeostasis
and generation of action potentials. Salty taste, one of the five basic tastes (sweet,
umami, bitter, sour, and salty), is considered to play essential roles in identifying andingesting the Na+ in foods. However, the molecular mechanisms underlying the salt
taste reception and its modulation are remained unclear in detail. Regarding the salt
taste reception, it has recently been revealed that the epithelial sodium channel (ENaC)
α subunit functions as amiloride-sensitive salt taste receptor in taste bud cells. Reninangiotensin system (RAS) is a major hormone system in the regulation of body fluid andsodium homeostasis. We had reported that a key component of RAS, angiotensin II(AngII) directly acts on taste cells via its receptor AT1, and suppresses amiloridesensitive salt taste responses. Furthermore, we recently revealed the presence of all
RAS components to produce AngII, namely, renin, angiotensinogen, and angiotensinconverting enzymes 1 and 2 (ACE1, ACE2) in mouse taste buds. These results indicate
the existence of a local RAS in the taste organ and suggest that taste function may beregulated by both locally-produced and circulating AngII. Such integrated modulation of
peripheral salt taste sensitivity by AngII may play an important role in sodium
homeostasis.
It is reported that early symptoms of coronavirus disease 2019 (COVID-19) may include
a loss of taste or smell, and SARS-CoV-2 uses human ACE2 as the entry receptor on hostcells. These results suggest that ACE2 expressed in the taste organs may be involved in
the development of the taste loss in COVID-19. In this presentation, we would also liketo discuss the possible linkage between the taste RAS and taste loss in COVID-19.

─ 56 ─Name: Noriatsu Shigemura, Ph.D
Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu University, Japan.

2000:

Bachelor of Arts degree in Dentistry (received from Kyushu University) and D.D.S(Doctor of Dental Surgery)
Doctor of Philosophy in Dentistry (received from Kyushu University)

Symposium I
Symposium II
Symposium III

Employment History:
2001-2008: Assistant professor
Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu
University(professor: Dr.Yuzo Ninomiya)
2008-2015: Associate Professor
Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu
University(professor: Dr. Yuzo Ninomiya)
2016-present: Professor
Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu
University
2018-present: Concurrent post
Research and Development Center for Five-Sense Devices, Kyushu University(Director of the center: Dr. Toshiro Matsui, Professor, Bioscience &Biotechnology, Faculty of Agriculture, Kyushu University)

Special Lecture

Postgraduate Education:
2000-2001: Postdoctoral associate,
Bio-oriented Technology Research Advancement Institution (NARO),
Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu
University(professor: Dr.Yuzo Ninomiya)

Greeting

Education:
1996:

Keynote Lecture

Brief CV

Rising Scientist Session
Poster Presentation

─ 57 ─

Symposium III
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 8 (Sun.) 13:50-14:00
SIII-2
Pathophysiology of SB: challenges from human andanimal studies

Takafumi Kato, D.D.S., Ph. D.
Osaka University Graduate School of Dentistry, Department of Oral Physiology

It becomes increasingly recognized that dentists can play roles in diagnosing andmanaging some sleep disorders, and their orodental consequences. Among them, sleep
bruxism (SB) is a common sleep disorder, affecting approximately 20% in children and
10% of adults. However, physiological studies are limited in humans and animals.
Polysomnographic studies in humans showed that rhythmic masticatory muscle activity(RMMA) occurred more frequently in patients with SB than in normal subjects. A
majority of RMMA occurred during NREM sleep in association with transient arousals
and cyclic sleep processes. To further understand the neurophysiological mechanismsof SB, the jaw motor activities were investigated in the naturally sleeping animals.
During sleep, animals exhibited a variety of masseter and digastric contractions.
Nonetheless, the RMMA episodes were found to occur during NREM sleep: the episodes
were associated with cortical and cardiac activations as found in humans. In addition,
animals showed phasic bursts of masticatory muscles, mimicking a coordinated patternof chewing, during REM sleep. To investigate the excitability of masticatory central
pattern generator (CPG), cortical descending tract, originating from cortical masticatory
area, was electrically stimulated during wakefulness and natural sleep. Stimulations
induced rhythmic masseter and digastric contractions during wakefulness and NREM
sleep. However, the response threshold was higher and the response latency was longer
during NREM sleep than during wakefulness. During REM sleep, stimulation induced
rhythmic digastric muscle contractions. The response threshold was higher while
response latency was similar in comparison to wakefulness and NREM sleep. These
results suggest that distinct modulation of the excitability in masticatory CPG during
sleep and wakefulness can underlie the increased occurrence of RMMA during NREM
sleep in patients with SB. The above findings suggest that naturally sleeping animals
can be used as an experimental model for investigating the pathophysiologicalmechanism of SB.

─ 58 ─

Keynote Lecture

Brief CV
Education :1988-1994
1994-1998

Osaka University Faculty of Dentistry
Osaka University Faculty of Dentistry Graduate School of Dentistry

Symposium IIAwards:1. Prix Jean-Paul Lussier (2001)
2. CADR Postdoctoral Research Award (2001)
3. IADR/Unilever Travel Award (2002)
4. IADR Distinguished Scientist Awards/Young Investigator Award (2005)
5. KAO Health Science Research Award (2011)
6. Yumikura Research Award (2014)

Symposium I

Societies:
IADR Neuroscience group: Secretary/Treasurer (2006-2008), President-elect (2008),
President (2009), Immediate past president (2010)

Special Lecture

2013-current: Osaka University Hospital Sleep Medicine Center
2016-Osaka University United Graduate School of Child Development

Greeting

Employment:
1998-2001: Postdoctoral fellow
2001-2003: Research Assistant
Hôpital du Sacré-Cœur de Montréal, Université de Montréal Faculté demédecine dentaire and Centre recherche en science de neurologique.
2003:
Associate Professor, Matsumoto Dental University
2007:
Chief, Matsumoto Dental University Hospital Dental Sleep Medicine Clinic
2008:
Associate Professor, Osaka University (Department of Oral Anatomy and
Neurobiology)
2016-current: Professor, Osaka University (Department of Oral Physiology)

Symposium III
Rising Scientist Session
Poster Presentation

─ 59 ─

Symposium III
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 8 (Sun.) 14:20-14:30
SIII-3
Common pathophysiological features in burning mouth
syndrome and irritable bowel syndrome

Masamichi Shinoda, D.D.S., Ph. D.
Department of Physiology, Nihon University School of Dentistry

Irritable bowel syndrome (IBS), one of the intractable bowel diseases, is known to afflict
10%–15% of the population in developed countries. Intriguingly, burning mouth
syndrome (BMS) which is famous as an intractable intra-oral sensory disorder and IBS
are characterized by altered sensory qualities, namely pain hypersensitivity in IBS and
BMS patients develops without any apparent pathological changes such as nerve injury,
inflammation, trauma or malignant tumor in the gastrointestinal tract and oral
mucosae. To illuminate these pathogenetic mechanisms, we developed a noninflammatory model of lower gastrointestinal tract and tongue pain hypersensitivity inthe mouse that reproduces these two important features (pain hypersensitivity andnon-apparent pathological changes) of IBS and BMS. Firstly, colon pain hypersensitivity
in the IBS was virtually absent in P2X3 knockout relative to wildtype mice. Intralumenal
release of the endogenous P2X receptor ligand did not differ between wildtype andP2X3 knockout mice or change after the occurrence of IBS. The EC50 of P2X3 ligand forthe fast current decreased in dorsal root ganglion (DRG) neurons innervating togastrointestinal tract mucosa in the IBS. The enhancement of purinergic signaling in
DRG neurons may contribute to colon pain hypersensitivity in the IBS. Secondary, we
found that the increase of Artemin (Artn) mRNA expression in the tongue mucosa of
BMS patients and the significant increase in Artn expression and heat hyperalgesia in
the tongue mucosa in BMS model mouse. The transient receptor potential vanilloid 1(TRPV1) antagonism or Artn neutralization inhibited the heat hyperalgesia. The increaseof TRPV1-IR trigeminal ganglion (TG) neuron innervating the tongue was significantly
reduced by Artn neutralization in the tongue mucosa. The TG neuronal hyperactivity
was also inhibited by Artn neutralization These present findings suggest that the tongue
Artn overexpression in the BMS causes heat hyper-responses in TG neurons via the
TRPV1 hyperexpression, resulting in tongue heat hyperalgesia.

─ 60 ─

Masamichi Shinoda
Department of Physiology, Nihon University School of Dentistry

Tohoku University, School of Dentistry, D.D.S.
Nagoya University, Graduate School of Medicine, Ph.D.

The 4th Asian pain symposium outstanding-poster award
Japanese Association for Oral Biology Rising Members Award

Symposium IIAwards2011
2012

Symposium I

Academic activity
Councilor, Japanese Association for the Study of Pain
Councilor, The Physiological Society of Japan
Councilor, Japanese Association for Oral Biology
Board of directors, Japanese Society of Orofacial Pain
Member, The International Association for the Study of Pain
Member, Society for Neuroscience

Special Lecture

Research Appointment
2003-2006
Assistant professor, Nagoya University
2006-2009
Postdoctoral associate, University of Pittsburgh, USA
2009-2011
Assistant professor, Nihon University
2011-2020
Associate professor, Nihon University
2020-current Professor, Nihon University

Greeting

Education
Undergraduate 1992-1998
Graduate
1999-2003

Keynote Lecture

Brief CV

Symposium III
Rising Scientist Session
Poster Presentation

─ 61 ─

Symposium III
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 8 (Sun.) 14:50-15:00
SIII-4
In vivo Dynamics of Dental Tissue Regeneration

Toshihide Mizoguchi, M. Sc., Ph. D.
Oral Health Science Center, Tokyo Dental College, Tokyo, Japan[Background] Reparative dentin formation is induced in response to severe dental
damage. This is a biological defense mechanism to regenerate the damaged hard tissue.
In this biological process, dental damage induces odontoblast death, after which dental
pulp stem cells differentiate into odontoblast-like cells, contributing to generate
reparative dentin. However, how damage induces this regenerative process remains
unclear. We hypothesized that odontoblast death induces the regeneration of damaged
dental tissue. In this study, we examined the effects of odontoblastic depletion on
dentinogenesis activation using a Cre/LoxP-based strategy.
[Methods] (1) To induce cell death specifically in odontoblasts using a Cre/LoxP-based
strategy, we confirmed the odontoblast-specific expression of green fluorescent protein(GFP) in type I collagen α [(Col1 (2.3)]-GFP mice, in which GFP is expressed under thecontrol of a 2.3-kb fragment of the Col1 promoter. (2) Col1 (2.3)-Cre; ROSA26-loxP-stoploxP-diphteria toxin (DT) receptor (DTR); Col1(2.3)-GFP mice were generated andadministered DT for 1 week to deplete odontoblasts, and the regeneration ofodontoblasts and reparative dentin formation were then analyzed.
[Results] (1) The expression of Col1 (2.3) promoter-inducible GFP was only detected inodontoblasts in the maxillary first molar, confirming that Col1 (2.3)-Cre was specifically
expressed in odontoblasts. (2) Odontoblasts were markedly depleted in maxillary firstmolars after DT treatment. (3) Depleted odontoblasts significantly recovered in a timedependent manner. (4) Regenerative odontoblast-like cells generated reparative dentin.
[Conclusion] Dentin formation increased in response to odontoblastic cell death in a
genetically modified mouse model. This suggests that there is a dental pulp niche
environment regulated by odontoblastic cell death and that this regulatory network isessential for the activation of reparative dentin formation.

─ 62 ─

Toshihide Mizoguchi
Oral Health Science Center, Tokyo Dental College

Faculty of Life Sciences, Tokyo University of Pharmacy and Life Sciences, B.Sc.
Faculty of Life Sciences, Tokyo University of Pharmacy and Life Sciences, M.Sc.
Faculty of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Ph.D.

Greeting

Education
1994-1998
1998-2000
2002-2005

Keynote Lecture

Brief CV

Academic Appointments
2000-2006 Research associate, Division of Hard Tissue Research, Institute for Oral Science,
Matsumoto Dental University
2006-2018
Senior lecturer, Division of Hard Tissue Research, Institute for Oral Science,
Matsumoto Dental University
2011-2014
Postdoctoral fellow, Albert Einstein College of Medicine, Stem Cell Institute2018-2019
Senior lecturer, Oral Health Science Center, Tokyo Dental College
2019-present Associate professor, Oral Health Science Center, Tokyo Dental College

Special LectureAwards2014
2015

Symposium I
Symposium II

2016
2016

Travel award, The 11th Bone Biology ForumBest presentation award, The 1st Japanese Society of Osteoimmunology
Meeting
Best presentation award, The 1st Oral Frontier Science Meeting
Research award, The 34th Japan Society for Bone and Mineral Research
Meeting

Symposium III
Rising Scientist Session
Poster Presentation

─ 63 ─RISING SCIENTIST SESSION

─ 65 ─

Rising Scientist Session
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 7 (Sat.) 13:20-13:30
RS-1
Factors secreted from dental pulp stem cells show
multifaceted benefits for Synergistically Regenerate
Transected Rat Peripheral Nerves by Altering
Macrophage Polarity.
Fumiya Kano, D.D.S., Ph. D.
Department of Tissue regeneration Institute of Biomedical Sciences, Tokushima
University Graduate School

Following peripheral nerve injury (PNI), Schwann cells (SCs) and macrophages
cooperatively promote nerve regeneration. The dam- aged axons and myelin sheaths
distal to the lesion undergo Wallerian degeneration, in which migrated macrophages
remove the myelin and axonal debris from the injury site, while the mature SCs thendedifferentiate and proliferate to form the bands of Bunger, a series of tubular structurethat produces trophic factors and extracellular matrix molecules that accelerate axonal
regrowth toward their original targets. Recent studies have also shown that fibroblasts
and endothelial cells/blood vessels in the PNI promote the sorting and directionalmigration of SCs, respectively. Thus, the temporal and spatial coordination of multiple
cell types promotes peripheral nerve (PN) regeneration. However, while the selfreparative activities of PNs successfully repair crush or cut-induced neuronal injuries,
they do not fully repair transection-induced nerve gaps, which are replaced with fibrotic
scars.
Stem cell transplantation-based therapy is a promising approach for patients withsevere PNI. The transplantation of various types of scaffolds containing bone marrowmesenchymal stem cells, adipose-derived stem cells, umbilical cord-derived
mesenchymal stem cells, or dental pulp stem cells into the transected nerves of rodents
promotes substantial functional recovery. Notably, in most of these studies,
neurological function is recovered primarily through paracrine/trophic mechanisms.
Stem cells secrete a broad repertoire of trophic and immunomodulatory factors thatcan be collected as serum-free conditioned medium (CM). We previously reported thatthe engrafted stem cells from human exfoliated deciduous teeth (SHEDs) and SHED-CM
exert similar therapeutic effects for Central Nervous System (CNS) injuries, acute liver
failure, and lung injuries.
However, the therapeutic mechanisms and factors in SHED-CM responsible for PN
regeneration are still largely unknown.
In this presentation, we report that SHED-CM regenerates PNs by inducing tissuerepairing M2 macrophages and may provide therapeutic benefits for severe peripheral
nerve injuries.

─ 66 ─

Fumiya Kano
Department of Tissue regeneration Institute of Biomedical Sciences, Tokushima University
Graduate School

2015
2016
2017

Symposium II

Excellence Title Award, The 36th Annual Meeting of the Japanese Society of
Inflammation and Regeneration.
Travel Award, 12th World Congress on Inflammation
Excellence Title Award, The 37th Annual Meeting of the Japanese Society of
Inflammation and Regeneration.
Excellence Title Award, The 63th Annual Meeting of Japanese Society of Oraland Maxillofacial SurgeonsSymposium I

Award:
2015

Special Lecture

Research & Professional Experience:
2010-2012
Department of Oral and Maxillofacial Surgery, Nagoya University Hospital
2012-2019
Department of Oral and Maxillofacial Surgery, Nagoya University Graduate
School of Medicine
2019-2020
Specially Appointed Assistant Professor, Tokushima University
2020Assistant Professor, Tokushima University

Greeting

Education
Undergraduate 2004-2010 Kanagawa Dental College, Yokosuka, Japan, D.D.S.
Graduate 2012-2016 Nagoya University Graduate School of Medicine, Nagoya, Japan, Ph.D.

Keynote Lecture

Brief CV

Symposium III
Rising Scientist Session
Poster Presentation

─ 67 ─

Rising Scientist Session
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 7 (Sat.) 13:50-14:00
RS-2
Phenotypic and neuroplastic changes in trigeminal
nociceptive pathways following trigeminal nerve injury

Ayano Katagiri, D.D.S., Ph. D.
Department of Oral Physiology, Osaka University Graduate School of Dentistry,
Suita, Japan

Trigeminal nerve injuries are often caused by dental and orofacial surgical procedures.
Patients with trigeminal nerve injuries suffer from complex symptoms, such as
persistent trigeminal neuropathic pain and affective distress, that interfere with daily
activities. The underlying mechanisms linking somatic and affective symptoms remain
to be clarified. We investigated the phenotypic and neuroplastic changes in trigeminal
ganglion neurons and trigeminal spinal subnucleus caudalis (Vc) neurons in trigeminal
neuropathic pain animal models that exhibited mechanical allodynia and heat
hyperalgesia.
In intact trigeminal ganglion, Aδ- and C-fiber afferents mainly transmit noxious
information, while Aβ-fiber afferents transmit mechanosensitive tactile information.
After the trigeminal nerves were injured, Aδ and C afferents became hyper-activated.
Moreover, Aβ- afferents have been shown to upregulate calcitonin gene-related peptide(CGRP), a neuropeptide that is generally synthesized and released in nociceptive Cafferents. Thus, in addition to Aδ and C afferents, Aβ afferents contribute to abnormal
nociceptive signaling in the secondary neurons in the Vc after nerve injury. Vc neurons
have projections that ascend to the ventral posteromedial thalamic nucleus (VPM)
associated with sensory discrimination and parabrachial nuclei (PBN). After trigeminal
nerve injury, C-fiber-mediated nociceptive inputs increased in Vc-VPM and Vc-PBN
ascending pathways. However, Aβ-fiber-mediated mechanosensitive nociceptive inputs
activated Vc neurons that specifically projected to the PBN. The PBN is a hub of multidimensional sensory processing, including visceral malaise, taste, temperature, itch, andaffective aspects of pain, to the thalamus, hypothalamus, and extended amygdala.
Therefore, our results suggest that phenotypic changes in Aβ afferents in the trigeminal
ganglion and neuroplastic changes of Vc projecting to the PBN can underlie thedevelopment of pain and affective symptoms after trigeminal nerve injury. The PBN is a
crucial structure for future investigations of the interaction between pain and affective
problems, such as sleep disturbance and anorexia, in trigeminal nerve injury.

─ 68 ─

Keynote Lecture

Brief CV
Ayano Katagiri

2014 - 2017

Department of Physiology, Nihon University School of Dentistry
Assistant Professor
2017 - present Department of Oral Physiology,
Osaka University Graduate School of Dentistry Assistant Professor

SHISEIKAI Scholarship Fund for basic researcher of medical science, Keiko
Watanabe Award

Symposium II

AWARDS
2020

Symposium I

WORK EXPERIENCESpecial Lecture

EDUCATION and TRAINING
2002 - 2008 Kyushu Dental University, Fukuoka, Japan DDS.
2008 - 2009 Department of Oral and Maxillofacial Surgery,Nihon University School of Medicine Itabashi Hospital,
Tokyo, Japan Residency
2009 - 2013 Department of Psychosomatic Dentistry,
Graduate School of Medical and Dental Sciences,
Tokyo Medical and Dental University, Tokyo, Japan Ph.D.
2012 - 2014 Department of Diagnostic and Biological Sciences,
University of Minnesota School of Dentistry, Minneapolis, MN
Post-doctoral Fellow

Greeting

Department of Oral Physiology, Osaka University Graduate School of Dentistry
1-8 Yamadaoka Suita-shi, Osaka, 565-0871, Japan

Symposium III
Rising Scientist Session
Poster Presentation

─ 69 ─

Rising Scientist Session
Lecture: Video On-demand distribution / Q & A: Live streaming
Q & A delivery time: November 7 (Sat.) 14:20-14:30
RS-3
The human brain and mastication; broad impact on
systemic functions

Jun Miyamoto, D.D.S., Ph. D.
Department of Maxillofacial Orthognathics, Graduate School of Medical and
Dental Sciences, Tokyo Medical and Dental University (TMDU)

Mastication is a complex movement coordinated among multiple dentomaxillofacialorgans, under control of brain functions based on varieties of inputs arising frommechano- and other sensory receptors richly distributed across dentomaxillofacial
structures. Particularly, sensory information from periodontal ligaments is crucial for
masticatory motor control, as numbers of animal and human studies demonstrate to
the date. Although, among research fields of human cerebral sensori-motor control,"teeth and masticatory movements" has been underemphasized compared to thestudies interested in other body parts.
Dentomaxillofacial sensory information, in addition to contribution to masticatory
sensori-motor control, also has implications on human cognitive and mental brain
functions. That is, tooth loss has been advocated as a risk factor for Alzheimer's disease,or dental sensory information apparently subserves memory functions. As such, toothderived sensation appears to have impacts on broad range of systemic functions
besides mastication, leaving numbers of subjects for future investigations.
Our department has been studying, using noninvasive brain imaging and eye tracking,the human cerebral organization of information processing for sensation from thedentomaxillofacial region, for masticatory motor control system, and for the effect ofmastication on broad systemic functions. Among these, in this presentation, I would liketo introduce: 1) reciprocal cortical activation patterns during incisal and molar biting
correlated with bite force levels, and 2) the effects of chewing on reducing appetite.
These results would not merely elucidate the effects of mastication on brain function,
but also pave the way for clarifying the relationship between oral function and general
health.

─ 70 ─

Jun Miyamoto
Department of Maxillofacial Orthognathics, Graduate School of Medical and Dental Sciences,
Tokyo Medical and Dental University (TMDU)

D.D.S,
Ph.D.,

Tokyo Medical and Dental University
Tokyo Medical and Dental University Graduate School

Symposium I
Symposium II

Award
IADR Unilever Hatton Divisional Award.
84th General Session & Exhibition of International Association for Dental
Research, Brisbane, Australia, 2006.

Special Lecture

Research and Clinical Appointments
2003-2005
Collaborative Researcher, National Institute for Physiological Sciences,
National Institutes of Natural Sciences
2007-2008
Clinical Fellow, Maxillofacial Orthognathics,
Tokyo Medical and Dental University Graduate School
2008-2010
Research Fellowship for Young Scientists,
Japan Society for the Promotion of Science
2005-current Visiting Researcher, National Institute of Neuroscience,
National Center of Neurology and Psychiatry
2010-current Assistant Professor, Maxillofacial Orthognathics,
Graduate School of Medical and Dental Sciences,
Tokyo Medical and Dental University

Greeting

Education
2001
2005

Keynote Lecture

Brief CV

Symposium III
Rising Scientist Session
Poster Presentation

─ 71 ─

POSTER PRESENTATION

─ 73 ─

001:

Wear Resistance of Novel Machinable Glass Ceramics
S. Kariya, T. Azuma, F. Fusejima
R&D Dept., GC Corporation, Tokyo, JAPANObjectives: In recent years, glass-ceramic blocks for CAD/CAM are clinically well accepted as “Single-Appointment Treatment”
material. Conventionally, Feldspar glass ceramics have been frequently selected. Recently, it has been developed a Novel
Lithium Disilicate Glass Ceramic which doesn’t require the crystallization process after CAD/CAM fabrication. The purpose ofthis study was to evaluate the wear resistance of machinable glass ceramic blocks.Methods: The wear resistance properties of a
Novel Lithium Disilicate Glass Ceramic Block “Initial LiSi Block” (LS, GC Corp.) and 2 different Feldspar glass ceramic blocks of “GC
Initial LRF BLOCK” (LRF, GC Europe N.V.) and “Block V” (BV) were compared by two-body wear test. Polished samples (Φ2.1mm)
were prepared with diamond polishing paste “Cera Shine” (GC Corp.). They were set and contacted with hydroxyapatite as
antagonist which sintered and polished with #4000 SiC paper in water. The wear test was performed with sliding on antagonist
under a load of 0.3kgf with 10,000 cycles. Wear amounts were evaluated by measuring sample height (n=4) before and after
wear test. In order to compare the crystal structure and the crystallinity, microscope observation with SEM (SU-70, HITACHI)
and Reference Intensity Ratio method (RIR) with XRD (Empyrean, PANalytical) were carried out.Results: The averages of wear
amount were LS 1μm, LRF 18μm and BV 39μm respectively and they showed significant difference in each other (p<0.01, Oneway ANOVA and Turkey test). On the observation of SEM, the crystal type differences were seen between Lithium Disilicate
and Feldspar. Moreover, the crystallinity of LS showed apparently higher than both LRF and BV. It was considered that the wear
resistance property is influenced by both crystal type and crystallinity.Conclusions: It is considered that LS could be one of themost attractive “Single-Appointment Treatment Glass Ceramic Material”, because of its high wear resistance.

002:

Evaluation of bonding layer durability on 2-step self-etch adhesive
K. FUJIMORI, K. HIRANO, F. FUSEJIMARESEARCH & DEVELOPMENT, GC CORPORATION, TOKYO, Japan

Objectives: In general, 2-step self-etch adhesives are reported relatively high bond strength. In 2-step self-etch adhesives,
they consist with first step PRIMER and second step BOND. The BOND form thicker bonding layer which contributes to makegood wettability with hydrophobic composite resin and develop the mechanical strength of entire bonding layer which
increase bonding performance. Therefore, durable composition might be suitable for the BOND. However, most of commercial
products contain hydrophilic monomers such as HEMA in the BOND which can expect less durability due to its water uptake.
We have developed a new 2-step self-etch adhesive (BZF-29) including the BOND with hydrophobic composition and HEMA
free. In this study, flexural strength was evaluated on several adhesive to find impact of hydrophobic composition on bonding
layer durability.Methods: The BOND of BZF-29 (GC, BZF), Product A (PA) and Product B (PB) were examined. Flexural strength
specimens were prepared in accordance with ISO4049:2019. The specimens were immersed in distilled water at 37 degC for
1, 7, 28 and 90 days respectively, and then measured flexural strength by using a universal testing machine (AG-IS, Shimadzu
Corporation) (n=5).Results: The flexural strength of PA and PB decreased significantly after 7 days of immersion, whereas thatof BZF showed no significant decrease even after 90 days of immersion. PA and PB contain HEMA in the BOND, which can be
expected to easily uptake water. Therefore, it is considered that their flexural strength was degraded due to water sorption. On
the other hand, BZF has highly hydrophobic composition HEMA free and did not show degradation by immersion.Conclusions:
Since the BZF-29 formulate hydrophobic composition and HEMA free on the BOND, its flexural strength did not degrade by
immersing in water even for long term. These results indicated BZF-29 can be expected to have excellent long-term durability inclinical practice.

─ 74 ─

Bonding properties of acrylic resin to zirconia and polyaryletherketone (PAEK)
T.-Y. PENG1, S. SHIMOE2, D.-J. LIN1, M. KAKU2
1

School of Dentistry, College of Dentistry, China Medical University, Taiwan R.O.C, 2Department of Anatomy and Functional
Restorations, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan

Greeting
Special Lecture

Objectives: With the rapid pace of technological development, CAD/CAM technology, low-wax techniques, and digital workflow
have become mainstream in laboratory and clinical dentistry. Furthermore, the popularization of aesthetic concepts has raised
doubts regarding the use of traditional alloy materials (Co-Cr) in removable partial dentures (RPD). This study aims to discuss
the bonding strength of aesthetic dental materials to acrylic resin and to assess the feasibility of using these aesthetic dental
materials in RPD applications.
Methods: Five types of testing materials were considered (control: Co-Cr; two zirconia-based materials: yttria-stabilized
tetragonal zirconia polycrystal (Y-TZP), and ceria-stabilized tetragonal zirconia/alumina nanocomposite (Ce-TZP/A); twopolyaryletherketone (PAEK) materials: polyetheretherketone (PEEK), and polyetherketoneketone (PEKK)). All sample surfaces
were prepared via grinding, sandblasting, and priming according to the manufacturer's instructions prior to the acrylic resin
polymerization. The surface roughness was measured using atomic force microscopy, and the shear bond strength (SBS) was
determined. The obtained data were analyzed using Tukey's HSD (α=0.05). After the SBS test, the interfacial failure modes wereobserved using a thermal field emission scanning electron microscope.
Results: The PAEK materials showed lower surface roughness than zirconia and Co-Cr alloy (P<0.05) after surface pretreatment.
Within the material group (zirconia or PAEK), there was no significant difference (P>0.05). Zirconia (Y-TZP=12.47±4.8 MPa; CeTZP/A=11.80±4.6 MPa) and Co-Cr alloy (11.73±1.82 MPa) had a comparable SBS, while the PAEK materials (PEEK=7.60±2.0 MPa;
PEKK=8.38±1.9 MPa) had a relatively lower SBS. Adhesive failure was the dominant failure mode in all the test groups.
Conclusions: The SBS values of the zirconia and PAEK materials with acrylic resins were consistent with the clinical guidelinesof ISO 10477 (>5.0 MPa). Within this feasibility study, these aesthetic dental materials were evaluated as potential alternative
materials for RPD frameworks.

Keynote Lecture003:

Symposium I

Bond strength between one-step adhesives and dentin after cyclic loading
T. EGOSHI1, Y. TAIRA1, K. SOENO2, K. KAIDA1, S. KUBO1, H. MURATA3
1

Division of Cariology and Restrative Dentistry, Department of Prosthetic Dentistry, Nagasaki University, Nagasaki, Japan, 2Department
of Appried Prosthodontics, Nagasaki University, Nagasaki, Japan, 3Department of Prosthetic Dentistry, Nagasaki University, Nagasaki,
Japan

Rising Scientist Session
Poster Presentation

─ 75 ─

Symposium III

Objectives: The purpose of this study was to investigate the influence of mechanical load cycling on the dentin bond strengthsof four different one-step self-etch adhesives.
Methods: Clearfil Tri-S bond (Tri-S, Kuraray Noritake Dental), BeautiBond (B-Bond, Shofu), Bond Force (Bond-F, Tokuyama
Dental), and G-Bond Plus (G-Bond, GC) were used as adhesives. Extracted non-carious human molars were sectioned at thecemento-enamel junction to expose the dentin and were ground flat with 600 grit silicon carbide papers. Dentin surfaces weretreated according to the manufacturers' instructions for each adhesive and a light-curing resin-composite material was built
up on the surface. All specimens were immersed in water at 37 ºC for 24 h. Half of the specimens were tested for micro-tensile
bond strength at a crosshead speed of 0.5 mm/min (0-cycle). The remaining half of the specimens were subjected to a verticalload (75.6 N, 1.2 Hz) on the top surface of resin composite with a 15º rotation using an acrylic stylus for 200,000 cycles, after
which the micro-tensile bond strengths were determined (200,000-cycle). The data were analyzed by two-way ANOVA and a
Tukey-Kramer HSD test at a statistical significance of 0.05.
Results: The mean bond strengths were G-Bond/0-cycle (78.3 MPa), Tri-S/0-cycle (70.9 MPa), B-Bond/0-cycle (67.3 MPa),
B-Bond/200,000-cycle (67.2 MPa), Tri-S/200,000-cycle (62.5 MPa), G-Bond/200,000-cycle (54.4 MPa), Bond-F/200,000-cycle(50.0 MPa), and Bond-F/0-cycle (44.7 MPa). Tri-S and B-Bond exhibited relatively high bond strengths before loading that did
not significantly change after 200,000 cycles (high). G-Bond had a high bond strength before loading that significantly decreased
after 200,000 cycles (slope). Bond-F resulted in a relatively low bond strength before loading that did not significantly decrease
after 200,000 cycles (moderate).
Conclusions: The influence of mechanical load cycling on the bond strength between one-step self-etch adhesives and dentin
could be divided into three categories: high, slope, and moderate.

Symposium II

004:

005:

Influence of saliva contamination on adhesion performance of adhesive resin cement
S. MURAKAMI, K. HIRANO, F. FUSEJIMARESEARCH & DEVELOPMENT, GC CORPORATION, TOKYO, Japan.

Objectives:The surface preparation of tooth abutment is important for adhesion performance of adhesive resin cement(ARC),
but clinically abutment surface might be accidentally contaminated by saliva(SC), which decrease adhesion performance due
to inhibit proper polymerization of ARC at adhesive interface where is difficult to light-cure. We have developed ARC, G-CEM
ONE EM, which accelerate polymerization performance even without light-irradiation at adhesive interface in combination with
Adhesive Enhancing Primer(AEP, formulated additional polymerization initiator). We evaluated influence of SC on Shear bondstrength(SBS) and polymerization rate(PR) of commercially available ARC.Methods:Two commercially available ARC, G-CEM ONE
EM with AEP(GO, GC Corporation)and productA were used in this study. Bovine tooth was grinded with 600-grit SiC paper toexpose dentin and separated in 2-groups, SC and control. On SC, human-saliva was applied to bonding surface, left to stand for
5seconds and dried with air. Then the bonding area(3.0mm diameter) and cement thickness(0.1mm) were defined. Stainlesssteel rod was bonded by ARC. Bonded specimen was stored in 37degC distilled water for 24hours and specimen was subjected
to be tested SBS by universal test equipment (SHIMADZU AG-IC, crosshead-speed 1mm/min, N=5). The PR of polymerized ARC
specimen was calculated by comparison of C=C bond intensity which in measured by FT-IR(Thermo Fisher Scientific, N=3). Data
were statistically analyzed by ONE-way ANOVA(Tukey-Krame).Results:SBS and PR of productA was significantly reduced by SC.
On the other hand, SBS and PR of GO was no significant difference between control and SC. This is indicated that SC has impact
to decrease SBS and PR of ARC and there was a correlation between PR and SBS.Conclusions:It might suggest polymerization
performance at adhesive interface is important to resist against SC and as result, G-CEM ONE EM with AEP which could
maintain polymerization performance even with SC had showed no significant decrease of SBS by SC.

006:

Evaluation of Dentin Anti-Demineralization potential of S-PRG Containing Self-Adhesive Resin Cement
S. ThanNaing1, N. Hiraishi1, A. Abdou1,3, J. Tagami1
1

Cariology and Operative Department, Tokyo Medical and Dental University, Tokyo, JAPAN, 2Department of Conservative Dentistry,
University of Dental Medicine Mandalay, Mandalay, Chanmyathazi, MYANMAR, 3Biomaterials Department, Faculty of Dentistry,
Modern University for Technology and Information, Cairo, EGYPTObjectives: to assess the anti-demineralization potential of S-PRG containing self-adhesive resin cement on dentin surfaces.
Methods: Fifteen round cavities (3.5 mm diameter and 1.5mm thickness) were prepared on bovine dentin slabs and werefilled with three self-adhesive resin cements (n=5); Exprimental silica filler containing cement (Si-based cement, Shofu, Japan),Experimental S-PRG filler containing cement (S-PRG-based cement, Shofu, Japan), and RelyX Unicem2 (F-based cement,
3M ESPE, Germany). After that all specimen surfaces were covered with acid-resistant nail varnish leaving a window areaof 4x4 mm2 to expose the dentin surface around the cement. All specimens were subjected to acidic challenge by using
remineralizing solution (Simulated Body Fluid-SBF) for 20 hours and demineralization solution (pH 4.5) for 4 hours alternatively(Re-De cycle). Depth of demineralization was assessed using Swept Source Optical Coherence Tomography (SS-OCT) after 7,
14, 21 and 28 days. Data were statistically analyzed using two-way ANOVA followed by multiple comparison with Bonferroni
correction.Results: For all groups, Re-De cycles showed significant increase in depth of demineralization after 14 and 28 days.
The depth of demineralization for S-PRG-based cement was significantly lower than Si-based cement after 7, 21 and 28 days
(p<0.05). Conversely, F-Based cement was not significantly different than Si-based cement after 7, 14, and 21 days (p<0.05).
Demineralization depth minimum limit after 28 days (DML) was around 95 μm. F-based and Si-based cements reached the
DML after 16 and 19 days, respectively.Conclusions: S-PRG containing self-adhesive resin cement capable of resisting dentin
demineralization after dynamic chemical formation of secondary caries.

─ 76 ─Preparation of Filler-Dispersed Resin Composite for Additive Manufacturing
P. KARNTIANG1, H. IKEDA2, Y. NAGAMATSU2, H. SHIMIZU2
1

Division of Operative Dentistry, College of Dentistry, Rangsit University, Pathum Thani, Thailand, 2Division of Biomaterials, Departmentof Oral Functions, Kyushu Dental University.

Greeting

Objective: To develop filler-dispersed resin composite for additive manufacturing. Method: STL data for 3D printing of a bar
sample was created using ChiTuBox software. A precursor for additive manufacturing was prepared via mixing TEGDMA-UDMA(1:1 ratio), a photo-initiator and silica filler (0.5 micron). There were 5 groups regarding filler load: 0%, 20%, 40%, 60%, 70%. The
total number of 36 samples per group were fabricated by a 3D printer and divided into 3 subgroups: (a) immediately received
the mechanical properties evaluation (flexural strength, flexural modulus and Vickers hardness); (b) was immersed in water for
2 months before mechanical properties evaluation; (c) received water sorption evaluation. Data were analyzed by 1 or 2way
ANOVA followed by Tukey test (p = 0.05).Result: Higher filler groups demonstrated higher mechanical properties and lower
water sorption values. 70% group had the highest mechanical properties and lowest water sorption values among all groups.
Water immersion decreased only flexural strength and Vickers hardness values, but not flexural modulus values.Conclusion:
All tested 3D-printed composites have met the requirements of ISO 10477:2018, indicating that the composites could be thepotential crown and veneering materials.

Keynote Lecture

007:

Special Lecture
Symposium I

Enamel Remineralization of TCP with Fluoride in Toothpaste: EPMA Study
H. HAMBA, H. ISHIZUKA, Y. MIYAYOSHI, K. NAKAMURA, T. MURAMATSU
Department of Operative Dentistry, Cariology and Pulp Biology, Tokyo Dental College, Tokyo, Japan

Rising Scientist Session
Poster Presentation

─ 77 ─

Symposium III

Objectives: This in vitro study aimed to compare the efficacies of experimental toothpastes containing functionalized
tricalcium phosphate (fTCP) with 950 and 1,450 ppm fluoride for enamel remineralization under pH cycling conditions using
microcomputed tomography (μCT) and electron probe micro–analyzer (EPMA).
Methods: Bovine enamel specimens were immersed in a demineralizing solution to create enamel subsurface lesions.
During pH cycling (12 days), the specimens were assigned into the following three groups based on the type of experimental
toothpaste (3M) used: DW (deionized water), TCP + 950F (fTCP with 950 ppm fluoride), and TCP + 1450F (fTCP with 1,450 ppm
fluoride). The μCT scans of all specimens were obtained after demineralization and pH cycling. Remineralization percentage(%R) was calculated from the mineral loss (Δ Z) after demineralization and pH cycling. The treated enamel lesions were finallyinvestigated using a scanning electron microscopy (SEM) and EPMA. One-way analysis of variance and post hoc Tukey´s tests
were used to analyze %R values.
Results: Mean %R value of DW (10.2%) was significantly lower than those of TCP + 950F (21.8%) and TCP + 1450F (24.7%)
groups (p < 0.05). However, the TCP + 950F and TCP + 1450F groups did not show significantly different %R values (p > 0.05) andshowed small crystals on the enamel rods in SEM. Furthermore, subsurface lesions of the TCP + 950F and TCP + 1450F groups
showed increased fluoride content in the EPMA line profiles. The TCP + 1450F group tended to have a higher fluoride uptake
than the TCP + 950F group according to EPMA mapping.
Conclusions: The experimental toothpastes containing fTCP with 950 and 1,450 ppm fluoride increased the remineralization in
the artificial subsurface enamel lesions during pH cycling. Toothpastes containing fTCP with 1,450 ppm fluoride may be moresuitable for remineralization in fluoride uptake into the subsurface lesions.

Symposium II

008:

009:

EVALUATION OF THE EFFECT OF ZINC-CONTAINING ORAL MATERIALS ON REMINERALIZATION USING INAIR MICROBEAM PIXE/PIGE
M. Sakurai1, Y. Matsuda2, K. Okuyama3, H. Yamamoto2, M. Hayashi2, T. Saito1
1

Division of Clinical Cariology and Endodontology, Department of Oral Rehabilitation, Health Sciences University of Hokkaido, Tobetsucho, Ishikari-gun, Hokkaido, JAPAN, 2Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of
Dentistry, Osaka, JAPAN, 3Department of Dental Materials Science, Asahi University School of Dentistry, Mizuho, Gifu, JAPANObjectives: Zinc, silver, and calcium ions have been explored recently for developing multifunctional bioactive materials. Zinc isreported to have an antibacterial and Matrix Metaroprotase (MMP) inhibitory effect, and a demineralization inhibitory effect.
We evaluated the demineralization prevention and zinc (Zn) uptake of an oral material into the dentin using an automatic pH
cycling.Methods: Each tooth was divided into four specimens. Their dentin in the buccolingual surfaces was exposed; the othersurface was covered with sticky wax. Specimens were demineralized in a buffer solution (0.2 M lactic acid, 3.0 mM CaCl2,
1.8 mM KH2PO4, 2% carboxymethyl cellulose, pH 4.5) at 37°C for 72 h. Moreover, 0.01% zinc chloride from a mouthwash(“Listerine”) and a solution containing 1% zinc chloride and 2% tannic acid were used. Specimens were stored in each material
at 37 °C for 24 h. From each tooth, 150 μm sections were prepared. The cut surface and half of the exposed area were covered
with sticky wax. The automatic pH-cycling system ((pH 6.8–4.5) simulated daily acid challenges in the oral cavity for two weeks.
The zinc and calcium distributions in the carious lesion in each specimen were evaluated using an in-air microbeam PIXE/PIGE
system. Multi-elemental sequential analyses were performed by measuring the concentrations of Ca and Zn using the in-air
microbeam PIXE/PIGE as per the previous report. For evaluating dentin remineralization, Ca concentrations on the covered anduncovered areas were compared.Results: The Zn concentration in the dentin showed significant differences among the threegroups (as per one-way ANOVA and Scheffe multiple comparison tests; p < 0.05). The Zn group showed a significant increasein Ca compared with the control group.Conclusions: The data from PIGE and PIXE techniques helped in understanding theefficacy of zinc-containing oral materials for preventing caries. This study was supported by Grants-in-Aid for Scientific Research(17K11712, 17H04382) from the JSPS.

010:

Dynamics of Ions Artificially Introduced into Caries-affected Dentin
K. NAITO1, H. YAMAMOTO1, Y. MATSUDA2, K. OKUYAMA3, M. HAYASHI1
1

Department of Restrative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, 2Division of Clinical Cariology
and Endodontology, Department of Oral Rehabilitation, School of Dentistry, Health Sciences University of Hokkaido, 3Department ofDental Materials Science, Division of Oral Functional Sciences and Rehabilitation, Asahi University School of Dentistry

Objectives : The aim of this study was to investigate how multi-ions from F-containing materials were incorporated into cariesaffected dentin.Methods : Human sound third molars (n=3) were used in this study. The roots were cut perpendicularly tothe axis at the cement-enamel junction and exposed the buccolingual dentin surfaces using a low-speed diamond saw. The
surface of specimens except the exposed root dentin was covered with sticky-wax. Demineralization was conducted by acetateacid (pH 5.0, 37°C) for 3 days to make the caries-affected dentin. These specimens were covered with following F-containing
materials (ZIF-10, Mi varnish® and FRC-02) (provided by GC), then placed in saline water for 3 months 37°C. The materials on
specimens were mechanically removed. In-air micro-particle induced X-ray / γ-ray emission (In-air μ-PIXE/PIGE) was performed
to measure Ca, F, Zn, Sr concentrations and to record the ion distributions before and after the application of the materials.
Then, the specimens were embedded by epoxy resin, polished until being mirror surface. Field Emission Scanning Electron
Microscope (FE-SEM) was performed for morphological observation.Results : F uptake was at constant with high concentrations
from the surface to approximately 200 μm layer. Zn and Sr were also incorporated into caries-affected dentin, and the highZn concentration in ZiF-10 was maintained beyond 200 μm. In F concentrations, there was a statistically significant difference
between ZiF-10 and the control group. There was no difference in the ion distributions among the materials. Conclusion : The
PIXE/PIGE enables us to observe the ionic dynamics of the caries-affected dentin due to high sensitivity to trace elements andmeasurement in air. The present study suggested that caries-affected dentin differed from the ionic dynamics of sound dentin.
This study was supported by Grants-in-Aid for Scientific Research (17H04382, 17K11705) from the JSPS.

─ 78 ─

Physical properties of Resorbable P(LA/CL) bilayer membrane for GBR
Y. SAKAGUCHI, E. ARIMA, K. YAMANAKA, F. FUSEJIMAGC Corporation

Greeting
Special Lecture

Objectives: Resorbable collagen membrane have been widely used for Guided Bone Regeneration (GBR). However, animal
derived collagen may carry a risk of unknown pathogen. In addition, most of the collagen membranes are weak under wet
condition and could easily be broken. To overcome these points, we have developed resorbable bilayer membrane usingsynthetic poly (L-lactide-ε-caprolactone) (PBM) with elastic characteristics. In this study, we aimed to evaluate physical andhanding properties of PBM under wet condition.Methods: PLGA membrane (PM) and Collagen membrane (CM) were used ascontrol. Tensile strength was measured by using universal testing machine(CR-500DX, SUN SCIENTIFIC CO., LTD) in dry and wet
condition (immersing to saline for 1 minutes). Both end of test specimen (2 mm x 15 mm) was fixed with jig, tensile strength
was measured at cross head speed of 20 mm/min until the specimen was broken. Flexibility was evaluated by using jaw model.
Test specimens (15 mm x 25 mm) in dry and wet condition was placed on jaw model to confirm whether test specimens could
fit the shape of jaw model.Results: [Tensile strength test] PBS showed elastic characteristic and was broken at longer distanceand low tensile strength. No difference between dry and wet condition was observed for PBM and PM. Tensile strength of CM
decreased under wet condition.[Flexibility] PBM in dry condition didn't fit the shape of jaw model, but PBM in wet condition
was able to fit the shape by adhering to the surface. PM didn't fit the shape of jaw model even in wet condition due to the solidcharacteristic. CM in dry condition didn't fit the shape of jaw model, but CM became softer by immersing to saline and fit theshape of jaw model easily.Conclusions: These results indicate that PBM has good handling in wet condition by maintaining themechanical strength, which could reduce the technical sensitivity when applying the membrane. Therefore, it is expected that
PBM is a clinically useful membrane for GBR.

Keynote Lecture011:

Symposium I

Influence of Molding Angle on 3D-printed Partial Denture Framework
H. KOBAYASHI1, A. TASAKA1, T. SHIMIZU1, S. HIGUCHI2, S. YAMASHITA1
1

Department of Removable Partial Prosthodontics, Tokyo Dental College, 2Wada Precision Dental Laboratories Corporation

Symposium III
Rising Scientist Session

By the development of the CAD/CAM technology, it became possible to apply selective–laser–sintering <SLS> technique tothe framework fabrication of the removable partial denture. However, various factors may affect the accuracy of fabrication
because of the complexity of framework design. In this study, it was aimed to clarify the effect of molding angle considered as
one of the factors on the shape accuracy of framework fabricated by SLS.
A partial edentulous mandible cast was scanned using dental laboratory scanner. Removable partial denture framework was
designed with an Akers clasp on the left first premolar, a ring clasp on the left second molar, a RPI clasp on the right second
premolar, and a lingual bar as a major connector <design data>. The framework was fabricated by SLS under two experimental
conditions; the molding angle was set to 0 and 45 degrees. Ten frameworks of each conditions were prepared. Heat treatment
was performed on the fabricated frameworks at the manufacturer´s recommended temperature. The production data of theframework was captured using a 3D scanner. The design data and the production data of frameworks were then superimposed
to compare the shapes of the rest, proximal plate, and the other components of Akers, ring and RPI clasps, center and joining
area of the lingual bar by using the 3D data inspection software.
The range of differences for the 0 and 45 degrees conditions were –0.14 to 0.14mm and –0.24 to 0.25mm, respectively.
Statistically significant differences were observed at the rest <ring clasp>, the proximal plates <ring clasp and RPI clasp>,
connectors, and clasp arms <p<0.05>.
This study showed that the molding angle affects the shape accuracy of the partial denture framework by SLS and suggested
that the effect of the setting of support pins depending on the molding angle.

Symposium II

012:

Poster Presentation

─ 79 ─

013:

Microbicidal effect and storage stability of neutral electrolyzed water-based gels
Y. NAGAMATSU1, H. NAGAMATSU2, H. IKEDA1, H. SHIMIZU1
1
Division of Biomaterials, Department of Oral Functions, Kyushu Dental University, Fukuoka, Japan, 2Division of Comprehensive
Dentistry, Department of Oral Functions, Kyushu Dental University, Fukuoka, Japan

Objectives: Electrolyzed waters mainly containing hypochlorous acid have come to be used in dental practice because of theirhigh microbicidal effect. For expansion of their application in dental treatment, we prepared a neutral electrolyzed waterbased gel in this study. The prototype gel was examined its microbicidal effect and storage stability to evaluate applicability as
an oral care gel. Methods: The prototype gel was prepared using with high-concentration neutral electrolyzed water having
approximately 1000ppm of available chlorine, distilled water and agar. Seven kinds of test gels were prepared by changing theconcentration to 0, 10, 15, 20, 30, 50 and 70ppm. Four microbes, Staphylococcus aureus, Streptococcus mutans, Enterococcus
faecalis and Candida albicans, were tested. Immediately after preparation, 9.0ml of each test gel was mixed to 1.0ml ofbacterial/fungi suspension (2×107 cells per ml of phosphate-buffered saline (PBS)), and treated for 3 min. After treatment,
1.0ml of the gel was diluted with PBS, the solution was added to agar culturing media, and incubated. Total number of thesurviving bacteria/fungi was calculated from the CFU in the media. As for the gel of 70ppm, the available chlorine concentration
was examined during 28-day storage in refrigerator. Results: The gel of 15ppm showed significantly higher bactericidal andfungicidal rates (>95% and >80% respectively). As for the gel of 20ppm, the rates were more than 99.999%. Furthermore,no surviving microbes were detected from gels of 30ppm or higher. As for the storage stability, the test gel showed a greater
decrease in available chlorine than neutral electrolyzed water during storage. However, it maintained effective available
chlorine concentration (>20ppm) having high microbicidal effects during 21-day storages. After 28-day storage, it could
maintain more than 15ppm showing enough microbicidal effects. Conclusions: It was suggested that the neutral electrolyzed
water-based gel has applicability as an oral care gel.

014:

A pilot study of effects on Dentifrice Containing Neem for Oral Malodor, Plaque Adhesion, Gingival
Inflammation and Oral Bacteria
M. YASUI, K. SHINADA
Department of Priventive Oral Health Care Sciences, Tokyo Medical and Dental University, Tokyo, Japan

Objectives: Azadirachta india (Neem) as an evergreen tree of the genus Azadirachta has been reported about antibacterial andplaque formation inhibitory effects in vitro studies. However, there have been few clinical studies of this dentifrice comparedwith other dentifrices. The aim of this study was to investigate effects of dentifrice containing neem on oral malodor andantibacterial and plaque inhibitory in vivo as a pilot study.
Methods: Four healthy adults (two males and females) participated in the study. The study was conducted by the crossover
method using dentifrices of containing neem, quasi-drug (fluoride and cetylpyridinium chloride containing) and cosmetic wereprepared. The subjects were instructed to brush with them at 3 times a day for two weeks. After experimental term, they had
a week washout period. At baseline and experimental two weeks after, we evaluated on oral malodor by Breathtron®(YOSHIDA.
CO.) and Oral Chroma™(Nissha FIS, Inc.), plaque adhesion (plaque index), gingival inflammation (gingival index, probing pocket
depth, and bleeding on probing) and oral bacteria in saliva by Bacterial counter®(PHC Holdings Corp.), Dentocult®-SM and
LB(Oral Care. Inc.).
Result: After two experimental weeks, the neem-containing dentifrice showed an improvement tendency in gingival
inflammation. On the other hand, the quasi-drug dentifrice showed an improvement tendency in oral malodor. However, there
were no significant differences between before and after and 3-experimental groups. This pilot study was carried out by small
number of subjects and short test period, so, it should be necessary to increase the number of subjects and the test period in
the future.
Conclusion: As a result of using a neem-containing dentifrice for 2 weeks, it may be suggested only an improvement tendency
on gingival inflammation, however, there were no significant effects on oral malodor, plaque adhesion, and oral bacteria.

─ 80 ─

Antimicrobial effects and mechanical properties of acrylic resin containing aPIZAS
K. INABA1, H. WATANABE1, Y. WADA1, S. WATANABE1, H. SASAKI1, H. HIRAMINE2, M. SASAKI3, T. NIHEI1, N. HAMADA1
1
Department of Oral Science, Kanagawa Dental University, Yokosuka, Japan, 2Department of Highly Advanced Stomatology, Yokohama
Clinical Education Center of Kanagawa Dental University, 3Nissho Chemistry Corporation

Greeting
Special Lecture

Objectives: Denture plaque and poor denture hygiene are associated with stomatitis. They may also serve as a reservoir ofpotential infectious pathogens, and may contribute to oral malodor. The prevention of microbial adhesion to denture surfaces
is essential for maintaining good oral hygiene and preventing plaque accumulation. The purpose of present study was toevaluate the antimicrobial effects and mechanical properties of acrylic resin containing aPIZAS. aPIZAS has been shown tosuppress the growth of fungi, bacteria, and algae, and is an antibacterial agent that is used in a wide range of fields. It is alsochemically stable and safe.Methods: Acrylic resin disk containing 1.5%, 1.0% and 0.5% aPIZAS were used in this study. Acrylic
resin disks containing aPIZAS on mechanical strength was evaluated by Water absorption test and three-point bending test.
The antimicrobial effects of aPIZAS and acrylic resin disks containing aPIZAS were performed using Streptococcus mutans,
Porphyromonas gingivalis and Candida albicans. The deodorizing activity of acrylic resin disks containing aPIZAS immersed in P.
gingivalis suspension was also examined.Results: The water absorption, flexural strength and flexural modulus of acrylic resin
disks containing aPIZAS were not significantly different from those of acrylic resin disks without aPIZAS. The aPIZAS showedbactericidal activity against P. gingivalis, S. mutans and C. albicans. Bacterial adhesion to the acrylic resin disks containing
aPIZAS was significantly lower than those of acrylic resin disks without aPIZAS. Acrylic resin disks containing aPIZAS deodorized
methyl mercaptan produced by P. gingivalis.Conclusions: Acrylic resin disks containing 1.0% aPIZAS were confirmed to exert
antibacterial effects and deodorant effects. Furthermore, the mechanical properties were similar to disks without aPIZAS. These
results suggest that acrylic resin disks containing aPIZAS is very useful as a dental material.

Keynote Lecture015:

Symposium I

Effects of S-PRG eluate on bacterial properties related to oral malodor
S. OMAGARI1, M. YONEDA1, N. SUZUKI2, D. GRENIER3, S. YAMAMOTO1, K. YAMADA1, J. HATAKEYAMA1, H. MORITA4, C.
KOGA5, T. HIROFUJI1
1

Poster Presentation

─ 81 ─

Rising Scientist Session

Objectives: A multi-ion releasing dental material, surface pre-reacted glass ionomer (S-PRG), is widely used for dental
treatments. The S-PRG filler particles are formed by an acid-base reaction between fluoroaluminosilicate glass and polyacrylic
acid. The aim of the study was to examine the effects of S-PRG eluate on several bacterial properties, including proteolytic
activity, auto-aggregation, interbacterial coaggregation, and volatile sulfur compounds (VSCs) production, which are considered
to be related to oral malodor.Materials and methods: The periodontopathic bacteria Porphyromonas gingivalis, Fusobacterium
nucleatum and Tannerella forsythia, as well as Streptococcus mutans, S. gordonii, and Escherichia coli were used in this work.
In some experiments, protease-deficient mutants of P. gingivalis were also tested. S-PRG eluate was provided by SHOFU INC(Kyoto Japan). The effect of S-PRG eluate on VSCs production by P. gingivalis was assessed using Gas Chromatography. The
effects of S-PRG eluate on protease activity was determined by monitoring the degradation of a chromogenic substrate. The
effects on auto-aggregation, coaggregation and growth were examined by spectrophotometry.Results: S-PRG eluate inhibitedthe in vitro production of VSCs. S-PRG eluate inhibited the protease activity of P. gingivalis and boron ion had the strongest
suppressive effect. S-PRG eluate induced auto-aggregation of periodontopathic bacteria, while it had few effect on the otherbacteria tested. A cell extracts of T. forsythia promoted the growth of P. gingivalis, but the presence of S-PRG eluate suppressed
this growth promotion.Conclusions: S-PRG eluate suppressed several properties of P. gingivalis that may interfere with VSCs
production. The use of S-PRG may represent a promising strategy to control oral malodor.

Symposium III

Section of General Dentistry, Department of General Dentistry, Fukuoka Dental College, Fukuoka, Japan, 2Section of Oral Public Health,
Department of Preventive and Public Health, Fukuoka Dental College Fukuoka, Japan, 3Groupe de Recherche en Ecologie Buccale,
Faculte de medecine dentaire, Universite Laval, Quebec, Canada, 4The Center for Visiting Dental Service, Department of General
Dentistry, Fukuoka Dental College, Fukuoka, Japan, 5Center for Oral Diseases, Fukuoka Dental College Fukuoka, Japan

Symposium II

016:

017:

Evaluation of anti-biofilm effects of bio-active GIC using a bioreactor
T. KOHNO, Y. LIU, F. DENG, R. TSUBOI, H. KITAGAWA, S. IMAZATO
Department of Biomaterials Science, Osaka University Graduate School of Dentistry, Suita, Japan

Objectives:
Previously, we reported that the glass-ionomer cement containing BioUnion filler (Caredyne-Restore, GC) demonstrated theeffects t o prevent adherence of oral bacteria on its surface due to the release of zi nc ion. Furthermore, we successfully
established a new bioreactor system tha t was able to produce biofilm similar to the one formed in vivo on re storative
materials. The aim of this study was to evaluate inhibitory effect s of Caredyne-Restore against biofilm formation using the newbioreactor.
Methods:
The disc specimens of Caredyne-Restore with a >diameter of 5 mm and a thickness of 1 mm were prepared. A bacterial
suspension (approx imately 105 CFU/mL) was prepared by diluting bacteria collected f rom human saliva with BHI medium, anddropped at 30 mL/hr onto each specimen fixed in the flow cell of the original bioreactor. The biofilm formed on th e surface
was observed and analyzed by using a confocal laser scanning micro scopy with LIVE/DEAD staining. The number of viablebacteria in the biofilm was determined by colony counting. For comparison, a conventional glass-iono mer cement (Fuji VII, GC)
and a resin composites (MI Fil, GC) were tested.
Results:
The image analysis revealed that the biofilm formed R>on the Caredyne-Restore was significantly thinner than that of Fuji VII
and MI Fil (p < 0.05, ANOVA, Tukey´s HSD test). The number of survi ving cells in the biofilm formed on the Caredyne-Restore
was significantly l ower than that of Fuji VII and MI Fil (p < 0.05). It is considered that the inhibitory effects against bacterial
adherence of Caredyne-Restore due to Zn ion-release resulted in less maturation of biofilm on its surface .
Conclusions:
The glass-ionomer cement containing BioUnion fil ler demonstrated the effects to inhibit oral biofilm formation on its surface.

018:

Streptococcus mutans inhibition by toothbrush monofilament with surface pre-reacted glass-ionomer
S. MATAYOSHI, T. KITAMURA, M. OTSUGU, R. NOMURA, K. NAKANO
Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Japan

Objective: Although a toothbrush is the most important self-care dental product, few available have inhibitory effects onoral bacteria. Surface pre-reacted glass-ionomer (S-PRG) filler releases six different ions; fluoride (F-), sodium (Na+), borate(BO33-), aluminium (Al3+), silicate (SiO32-), and strontium (Sr2+), which are known to have antimicrobial activities towards
Streptococcus mutans, a major pathogen of dental caries. In the present study, monofilaments containing different amounts of
S-PRG filler were developed for toothbrushes, with analyses performed to determine their effects on inhibition of S. mutans.
Methods: Nylon and polyester monofilaments containing either 20%, 1.4%, or 0% S-PRG filler were prepared. First, eachtype of monofilament was immersed in sterilized distilled water for 18 hours, then the amounts of the six ions released were
measured. Next, each monofilament type was immersed in an S. mutans bacterial broth containing 1% sucrose to analyze
biofilm formation and bacterial adhesion, after which the monofilaments were removed from the broth and the numbers of S.
mutans that survived in a dry condition were counted.
Results: As compared to polyester, the nylon monofilaments released larger amounts of ions from the S-PRG filler. Furthermore,bacterial broth with monofilaments containing S-PRG filler showed lower amounts of formed biofilm containing S. mutans thanbroth with monofilaments without the filler. Additionally, S. mutans organisms adhered to monofilaments containing S-PRG
filler were more easily exfoliated and eliminated in a dry condition as compared to those without the filler. Finally, effects toinhibit S. mutans were greater with nylon than polyester monofilaments, whereas no inhibitory effects by either type without
S-PRG filler were observed.
Conclusion: Monofilament containing S-PRG filler releases ions that have an inhibitory effect on S. mutans. The present findings
indicate the effectiveness of this material for use in toothbrushes.

─ 82 ─Comparison of microbiome organized on denture base materials and hydroxyapatite
Y. NEZU1, M. RYU1, K. ISHIHARA2, T. UEDA1
1

Removable Prosthodontics & Gerodontology, Tokyo Dental College, Tokyo, Japan, 2Microbiology, Tokyo Dental College

Greeting
Special Lecture

Objectives: Oral microorganisms colonize oral surfaces by forming biofilms. Dentures sometimes act as reservoirs of bacteria in
people with insufficient oral hygiene practices. Biofilms on the surface of dentures are thought to increase the risk of aspiration
pneumonia in the elderly. However, how oral microbe communities organize into biofilms has yet to be fully clarified. In thisstudy, we investigated the composition of biofilms on denture base materials in vivo.Methods: Thirteen healthy individuals
were enrolled in this study. Disk shaped denture material specimens composed of polymethyl methacrylate (PMMA), cobaltchromium (CoCr) alloy, and hydroxyapatite (HA) were worn by subjects for 48 h attached to an appliance in the oral cavity.
The V3-V4 region of 16S rRNA coding sequences from bacteria in the biofilms that formed on the denture materials weresequenced by Mysec. Qiime2 and LEfSe analysis identified the operational taxonomical unit (OTU) in biofilms on each materialand characterized the prevenance of the OTUs.Results: The average number of sequence reads per sample was 97,005 ±
91,523. Among the sequences from all samples, 328 OTUs were detected. The α diversity of the sample from CoCr was lower
than that of HA; however, the difference was not significant. The composition of the microbiome did not differ at the genus
level among the three materials, according to UniFrac analysis. Using LEfSe analysis, 10 genera showed differences between
PMMA and HA.Conclusions: This study showed that each denture material supports the formation of a similar microbiome. This
result suggests that the choice of material has little effect on the composition of the bacterial flora.

Keynote Lecture019:

Symposium I

ABC transporter activities in biofilm formation by Streptococcus mutans
K. GOTO, M. MATSUMOTO-NAKANO
Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences,
Okayama, Japan

Rising Scientist Session
Poster Presentation

─ 83 ─

Symposium III

ObjectiveStreptococcus mutans, a biofilm forming bacterium, has been found to possess over 60 ATP-binding cassette(ABC) transporters in gene analysis. ABC transporters have important functions related to gathering nutrients and exporting
unnecessary materials, and are considered to be involved in biofilm formation by S. mutans. In the present study, we identified
ABC transporter-related biofilm formation by the bacterium and analyzed related functions.MethodsInformation regarding the
SMU1520 gene encoding ABC membrane transporters possibly associated with biofilm formation was extracted from a database
containing the entire amino acid sequence of the S. mutans UA159 strain. To investigate the role of SMU1520, we constructed
an SMU1520-deletion mutant strain (Δ1520) of S. mutans MT8148. The upstream region of SMU1520, an erythromycin cassettegene, and the downstream region were amplified by PCR using specific primers, then those three products were combined andtransformed into S. mutans MT8148 using a double-crossover recombination method to construct Δ1520. To examine bacterial
growth, MT8148 and Δ1520 were grown for 18 hours at 37°C, then inoculated into fresh Todd Hewitt broth at 37°C. Absorbanceat 600 nm was measured every 1 hour using a spectrophotometer. Assays of biofilm formation by MT8148 and Δ1520 werethen performed, and biofilm structures were observed using confocal laser scanning microscopy (CLSM).ResultsThe growthrate of Δ1520 was slightly lower than that of MT8148. Furthermore, the quantity of biofilm formed by Δ1520 was significantly
decreased, with a reduction rate of 55%. Additionally, CLSM results demonstrated that biofilm formed by Δ1520 was morecoarse as compared to that formed by MT8148.ConclusionThe present results suggest that SMU1520 contributes to bacterial
growth and biofilm formation by involving export/import molecules. This study was supported by JSPS KAKENHI grants(20K18757).

Symposium II

020:

021:

Inhibitory Effect of Cyclodextran on Glucosyltransferase B in Streptococcus mutans
H. ASAUMI, K. GOTO, M. MATSUMOTO-NAKANO
Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences,
Okayama, Japan

Objective Streptococcus mutans, a primary causative agent of human dental caries, produces three types of glucosyltransferases(GTFs; GTFB, GTFC, GTFD), which synthesize adhesive glucan from sucrose. Among them, GTFB synthesizes the insoluble glucan
and has the strongest caries properties. Cyclodextran, a cycloisomaltooligosaccharide (CI) with a structure in which 7 to 12
glucoses are cyclically linked by α-1,6 bonds that has been shown to have inhibitory effects on GTFB, though the mechanism
remains to be elucidated. In this study, recombinant GTFB (rGTFB) was used to determine the mode of inhibition of GTFB by
CI.Methods Recombinant plasmid pSK6 carrying gtfB of S. mutans MT8148 was used. Escherichia coli XL-2 specimens harboring
pSK6 were cultured in Luria-Bertani broth. After harvesting bacterial cells by centrifugation, they were suspended in phosphatebuffer, and the suspension was sonicated using an ultra-disrupter. A supernatant of the lysate was obtained by centrifugation,then rGTFB was purified using column chromatography and added to phosphate buffer that included 0-25 mM sucrose and CI
at 0% or 0.25%. After 16 hours of incubation, synthesized insoluble glucan was determined based on absorbance at OD550.
ResultsThe glucan synthesizing activity of rGTFB reached a plateau when the sucrose concentration was 12.5 mM, both in thepresence and absence of CI. In contrast, kinetic analysis showed that the quantity of glucan produced by rGTFB was reduced byaddition of CI. ConclusionsKinetic analysis results showed that the glucan-producing activity of rGTFB reached a plateau bothwith and without CI when the concentration of sucrose was changed. These findings suggest that the inhibitory effect of CI on
GTF may be competitive. This study was supported in part by the Fund for Scientific Promotion of Nissin Sugar Co., Ltd., Tokyo,
Japan.

022:

The effects of fatty acid salts against Streptococcus mutans biofilm
A. KURAHASHI, K. WATANABE, T. SATO, K. INABA, H. SASAKI, N. HAMADA
Department of Oral Science, Graduate School, Kanagawa Dental University

Soap is consisited of several kinds of fatty acid salts. The antimicrobial activity of fattty acid salts against oral bacteria has
not been well known. Therefore, we examined the antimicrobial activity of fatty acid salts against oral microorganisms.
We used ten species of microorganism (Streptococus mutans, Actinomyces naeslundii, Lactobacillus casei, Porphyromonas
gingivalis, Prevotella intermedia, Fusbacterium nucleatum, Aggregatibacter actinomycetemcomitans, Staphylococcus aureus,
Escherichia coli, Candida albicans) and nine kinds of fatty acid salts (C4K, C6K, C8K, C10K, C12K, C14K, C18:1K, C18:2K, C18:3K).
The antimicrobial activity was examined by minimum bactericidal concentration (MBC) and counting a number of colony
forming units (CFU) after treatment with fatty acid salts for 5, 15, 60 minutes. Moreover, cytotoxicity of fatty acid salts on
gingival fibroblast was investigated. Additionally, the effect of fatty acid salts against S. mutans biofilm was investgated. C12K
showed high antimicrobial activity against all oral bacteria and killed at 1.4 mM. Additionally, C18:2K and C18:3K showed
high antimicrobial activity against all oral bateria except A.actinomycetemcomitans. C8K, C10K, C12K, C14K, C18:1K, C18:2K
and C18:3K showed antimicrobial activity against S.mutans, A.actinomycetemcomitans, P.gingivalis after treatment with fatty
acid salts for 5 minutes. However, they showed less antimicrobial activity even though they exposed against C.albicans for 60
minutes. C4K, C6K and C8K were not observed in the cytotoxic effect on gingival fibroblast at any of concentrations. C10K, C12K,
C14K, C18:1K, C18:2K and C18:3K suppressed S. mutans biofilm at all concentrations. These results suggest fatty acid salts may
be useful for preventing dental caries and periodontal disease and improving oral health.

─ 84 ─

Evaluation of collagen-binding properties of killed Streptococcus mutans strains
Y. SUEHIRO, S. MATAYOSHI, M. OTSUGU, R. NOMURA, K. NAKANO
Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Osaka, Japan

Greeting
Special Lecture

Objective: Streptococcus mutans, a major pathogen of dental caries, is regarded as a causative agent of infective endocarditis(IE). Cell surface proteins of S. mutans, such as 120 kDa collagen-binding protein (CBP) and 190 kDa protein antigen (PA),have effects on its collagen-binding property and are considered to be involved in IE pathogenicity. In addition, bacterial DNA
encoding CBP is frequently detected in heart valve specimens extirpated from IE patients, though live S. mutans organisms
are rarely isolated. Here, the collagen-binding properties of killed S. mutans strains were evaluated, with focus on CBP and PA
expression.
Methods: S. mutans strains were divided into three groups, CBP+/PA- (n=10), CBP+/PA+ (n=10), and CBP-/PA+ (n=10), thencultured and prepared under 3 different conditions; living, killed by formalin, and killed by autoclave. Next, each strain wasadded to a 96-well plate coated with type I collagen and cultured at 37 degrees for three hours, then staining with crystal violet
was performed. The OD595 value of each S. mutans strain was determined, with the value of TW871 (CBP+/PA+) defined as
100%.
Results: As for the living S. mutans strains, the average collagen-binding rate in both the CBP+/PA- and CBP+/PA+ groups wasapproximately 100%, whereas the CBP-/PA+ group showed nearly no collagen-binding ability. When S. mutans strains were
killed by formalin, the average collagen-binding rate for the CBP+/PA- group was 36.3%, significantly higher than that for the
CBP+/PA+ group (12.1%) (P<0.01). In contrast, nearly no collagen binding ability was observed in any group after killing byautoclave.
Conclusion: The present results indicate that CBP-positive S. mutans strains killed by formalin have a collagen-binding property,
with CBP+/PA- strains showing significantly higher collagen-binding than CBP+/PA+ strains. In addition, they suggest that killed
CBP-positive S. mutans strains without PA expression may have high pathogenicity towards IE.

Keynote Lecture023:

Symposium I

Screening of S. salivarius isolates with anti-caries activities
H. NAKADE1, S. ALI2, D. DUFOUR2, C. LEVESQUE2, S. GONG2
1

Faculty of Dentistry, Tokyo Medical and Dental University, 2Faculty of Dentistry, University of Toronto

Rising Scientist Session
Poster Presentation

─ 85 ─

Symposium III

Purpose:To screen for potential probiotic Streptococcus salivarius strains with anti-caries activities
Methods:
Tongue and plaque samples were processed for the isolation of S. salivarius using culture and the presence of a S. salivarius
specific gene, gtfk, by PCR. Deferred antagonism assays were next performed to confirm their inhibitory activities against S.
mutans, S. pyogenes and Micrococcus luteus. The presence of known bacteriocin genes in these isolates were next studied by
PCR using gene-specific primers.
Results:
Two hundred and twenty-nine (229) bacterial isolates were obtained from tongue swabs and plaque of 31 subjects. Amongthem, 170 (170/229=74%) isolates were determined to be S. salivarius based on morphology and the presence of gtfk gene.
Seventy-four isolates were found to possess inhibitory activities against the growth of S. pyogenes or Micrococcus luteus. Only
two isolates, 570-P1 and 372-P1, demonstrated inhibitory activities against the growth of S. mutans in addition to S. pyogenes
and Micrococcus luteus. Both 570-P1 and 372-P1 contained salA but did not carry salB, sal9 and sldA2 bacteriocins.
Discussion:
570-P1 and 372-P1 are anti-caries S. salivarius isolates with potential use as probiotics against dental caries. Although these
two isolates contain salA, it is known not to have anti-S. mutans activities so far. Therefore, it is possible that 570-P1 and 372-P1
produce other bacteriocins that show inhibitory effects on S. mutans. Further studies at biochemical and molecular levels, e.g.,
mass-spectrometric analyses and whole genome sequencing, will be conducted to identify the bacteriocins to understand themolecular regulation of their anti-S. mutans activities.

Symposium II

024:

025:

Characteristics of anti-periodontal bacterial activity in culture supernatant of probiotic
T. KAWAI1, R. SHIN2, Y. ITO2, S. IKAWA3, T. TANAKA3, T. OHSHIMA1
1
Department of Oral Microbiology, Tsurumi University School of Dental Medicine, Kanagawa, Japan, 2ALA Research Institute for
Fermentative Microbes, Tokyo, Japan, 3Technology Research Institute of Osaka Prefecture, Osaka, Japan

Objectives: Recently, the use of probiotics to prevent oral diseases is on focus. However, the probiotic mechanism against
periodontal pathogens has not been elucidated. For clarification, we analyzed the characteristics of the active components
in the culture supernatant produced by Lactobacillus fermentum ALAL020 (Lf020), which has antibacterial activity against
Porphyromonas gingivalis.Methods: The culture supernatant of Lf020 was heated to 37 °C, 60° C, 100° C and 121° C for 15
minutes to compare the antibacterial temperature sensitivity against the P. gingivalis type strain. We also compared theantimicrobial susceptibility to other P. gingivalis strains and the inhibitory effect of trypsin-like enzyme (gingipain) activity.
Further, we have already reported that the antibacterial components include a cyclic-dipeptide (2016 IADR). Here a synthesized
dipeptide was used to test the antibacterial activity against P. gingivalis and Prevotella intermedia as well as the gingipain
inhibitory test.Results: The antibacterial activity of the culture supernatant of Lf020 against P. gingivalis was reduced to half
by temperature treatment at 37 ° C or higher, but not further even when the temperature was raised. The antibacterial test
results with several strains of P. gingivalis showed differences in susceptibility. The gingipain inhibitory test suppressed all P.
gingivalis strains by the Lf020 culture supernatant. The synthetic dipeptide showed antibacterial activity at 5 mg/ml against P.
gingivalis and P. intermedia, but did not have an inhibitory effect on gingipain activity.Conclusions: The culture supernatant of
Lf020 was thermostable and effective against all strains of P. gingivalis, but there were differences in sensitivity. The synthetic
dipeptide showed antibacterial activity at the same concentration as the natural antibacterial dipeptide purified from theculture supernatant of Lf020, but gingipain inhibition was not observed. Therefore, it is likely that other substances suppress P.
ginigvalis in the culture supernatant of Lf020.

026:

Exploring for prevention of periodontal disease using products of the probiotic bacteria, genus
Lactobacillus -Targeting the genus PorphyromonasY. SAKAI, T. OHSHIMA, T. KAWAI
Tsurumi University Faculty of Dentistry Department of Dentistry

Objectives:There are problems such as allergy and the emergence of drug-resistant bacteria in prevention and treatment withcurrent antibacterial and antiseptic agents against periodontal disease. As one way to overcome them, it was hypothesizedthat metabolic substances produced by probiotic lactic acid bacteria have the effect of suppressing the growth of periodontal
pathogens and suppressing the activity of gingipain (trypsin-like enzyme) and can be used for prevention. However, because
lactic acid bacteria produce organic acids, the risk of dental caries was also considered, so we searched for strains which
produce effective metabolic products under neutral pH conditions. Methods:The supernatants of 13 test strains of Lactobacillus
culture in MRS medium (CS) were used in a state of pH7. The minimum inhibitory concentration were determined for three
Porphyromonas (P. gingivalis, P. salivosa, P. gulae) as a periodontal pathogen. To test the suppression of gingipain (trypsin-likeenzyme) activity, each Porphyromonas cell extract was mixed with a CS and brought to reaction with BA(P)NA, and measured
the absorbance. Results: As a result of the antibacterial activity test, several strains of Lactobacillus exhibited growth inhibitory
effect on all three Porphyromonas genera. When the inhibitory effect on the activity of gingipain, which is one of the main
pathogenic factors of Porphyromonas was examined, the effect onP. gingivalis was remarkable. Conclusion: For multiple culture
supernatants of Lactobacillus strains, the usefulness has been confirmed in antibacterial tests. Some of them are different fromstrains with strong with strong inhibition against gingipain activity, therefore it is considered important to use multiple strains
simultaneously in clinical application. Utilizing the supernatant ingredients at a neutral pH as oral probiotics without the risk ofcaries occurrence could make the suppression of periodontal disease possible.

─ 86 ─

Gemella haemolysans specifically inhibits the growth of Porphyromonas gingivalis
T. MIYOSHI1, N. YOSHINARI2, A. YOSHIDA1
1
Department of Oral Microbiology, Matsumoto Dental University, Nagano, Japan, 2Department of Periodontology, Matsumoto Dental
University, Nagano, Japan

Greeting
Special Lecture

A number of bacteria with hemolytic activity to degrade erythrocytes have been reported for serious human infections.
However, the characteristics of hemolytic bacteria in saliva have been largely unknown. The purpose of this study is toinvestigate the characteristics of hemolytic bacteria and clarify the relationship with periodontal disease (PD). Resting saliva
was obtained from a total of 15 people, including 10 PD patients and 5 healthy donors. A person with a periodontal pocketwith a depth of 4 mm or more was diagnosed as a PD patient. The hemolytic properties of bacteria were investigated throughthe formation of hemolytic bands by applying saliva on horse blood agar medium and culturing under anaerobic conditions
at 37ºC. Identification of hemolytic bacteria was performed based on the 16S rRNA sequence. The proportion of hemolytic
bacteria in saliva was carried out by quantitative PCR method. Growth competitive inhibition experiment between bacterial
strains was evaluated by culturing under anaerobic conditions at 37ºC. Hemolytic bacteria in saliva were abundant not only inpatients with periodontitis but also in healthy subjects. Many of the hemolytic bacteria in saliva are Gemella, and we identified
three species of these bacteria, G. sanguinis, G. haemolysans and G. morbillorum. In addition, G. haemolysans was significantly
higher in saliva of healthy subjects than in that of periodontitis patients. Furthermore, an experiment of competitive growth
inhibition to investigate the relationship between G. haemolysans and periodontal-pathogenic bacteria indicated that G.
haemolysans directly inhibited the growth of P. gingivalis. It was revealed that hemolytic G. haemolysans is present at a higher
ratio in the saliva of healthy subjects compared to PD patients. In addition, the growth of P. gingivalis is directly inhibited by G.
haemolysans. These results indicate that G. haemolysans is an important bacterial species for keeping the oral environment
healthy.

Keynote Lecture027:

Symposium I

Fusobacterium nucleatum metabolically integrates commensals and pathogens in oral biofilms
A. SAKANAKA1, M. KUBONIWA1, S. SHIMMA2, S. MAYUMI1, R. LAMONT3, E. FUKUSAKI2, A. AMANO1
1

Department of Preventive Dentistry, Osaka University Graduate School of Dentistry, Osaka, Japan, 2Department of Biotechnology,
Osaka University Graduate School of Engineering, Osaka, Japan, 3Department of Oral Immunology and Infectious Diseases, School of
Dentistry, University of Louisville, Louisville, KY, USA

Rising Scientist Session
Poster Presentation

─ 87 ─

Symposium III

Objectives
Fusobacterium nucleatum, a common oral microbiota constituent in both periodontal health and disease, is well-known for
its adhesive properties in oral biofilms; however, metabolic aspects of F. nucleatum within polymicrobial communities remain
relatively unknown. Previously, we discovered that Streptococcus gordonii, an oral commensal, secretes ornithine via anarginine-ornithine antiporter (ArcD), which in turn supports the growth and biofilm development of F. nucleatum. Here we
introduce another oral commensal, Veillonella parvula, further dissect the metabolic interactions mediated by F. nucleatum
within multi-species consortia and explore their impact on periodontal pathogenesis.
Methods
Intra- and extracellular metabolite changes in F. nucleatum when co-cultured with S. gordonii (WT or ΔarcD) and/or V. parvula
were examined using capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS) and ultra-performance liquid
chromatography (UPLC). qRT-PCR was used to confirm differential gene expression. Mass spectrometry imaging was performed
for polyamine visualization. Biofilm formation was assessed using confocal laser scanning microscopy.
Results
Transcriptional and CE-TOFMS-based metabolomic analyses showed that when co-cultured with S. gordonii WT, F. nucleatum
increased amino acid availability to enhance the production of butyrate and putrescine, a polyamine produced by ornithine
decarboxylation. Co-culture with V. parvula also increased lysine availability, promoting cadaverine production by F. nucleatum.
UPLC analyses using an ΔarcD mutant confirmed that ArcD-dependent ornithine excretion by S. gordonii induces synergistic
putrescine production, and mass spectrometry imaging revealed that this metabolic capability creates a putrescine-richmicroenvironment inside F. nucleatum biofilms. We further demonstrated that polyamines caused significant changes in thebiofilm phenotype of a periodontal pathogen, Porphyromonas gingivalis, with putrescine being a potent stimulator of biofilm
development and dispersal.
Conclusions
Collectively, our results highlight the ability of F. nucleatum to induce synergistic polyamine production within multi-species
consortia and provide insight into how the trophic web in oral biofilm ecosystems can eventually shape disease-associatedcommunities.

Symposium II

028:

029:

Analysis of novel genotypes of Mfa1 fimbriae in Porphyromonas gingivalis
K. SAKAE1, K. NAGANO2, Y. HASEGAWA1
1

Department of Microbiology, School of Dentistry, Aichi Gakuin University, Aichi, Japan, 2Department of Microbiology, School of
Dentistry, Health Sciences University of Hokkaido, Hokkaido, Japan

Objectives: Porphyromonas gingivalis, a periodontopathogenic gram-negative obligate anaerobic bacterium, generally
expresses two types of fimbriae, FimA and Mfa1. Whereas FimA fimbriae are known to have I–V genotypes, the genotypes ofMfa1 fimbriae have not been fully clarified. In recent years, we have analyzed the genotypes of mfa1 in 84 strains from ourlaboratory stock and have shown that mfa1 has at least two different genotypes, namely mfa70 and mfa53. Through a series ofanalyses, we identified eight strains that could not be classified as either mfa70 or mfa53. In the present study, we performed
whole-genome sequencing to classify the genotypes of mfa1 in these eight strains. Methods: Genomic DNA was extracted fromthe P. gingivalis strains 222, 1436, 1439, B158, EM3, JKG9, JKG10, and Kyudai-3, and sequenced using the Illumina NovaSeq
PE150 system. After the raw sequences were trimmed and filtered for quality, the remaining reads were assembled de novo
using BioBam OmicsBox. Based on the similarity of nucleotide and amino acid sequences, the protein-coding sequences ofthe strains were compared between the draft genomes using ClustalW. Results: Mfa1 fimbriae were composed of five proteins
expressed from the mfa cluster (mfa1–mfa5) in the type strain of ATCC 33277; however, it was found that the von Willebrandfactor-containing protein (VWA) gene corresponding to mfa5 was present in tandem in the EM3 and JKG10 strains. Notably,
VWA was presented alone without mfa1–mfa4 in the 222 strain. It was also found that only mfa1 exists independently in the
Kyudai-3 strain. Conclusions: We found the diversity of the mfa cluster among P. gingivalis strains. The genotyping of Mfa1
fimbriae requires sequence analysis to determine the presence or absence of the whole mfa cluster, including mfa1–mfa4 andVWA combination.

030:

Role of hyalin-like protein in biofilm formation by Capnocytophaga ochracea
T. WARITA1, K. SHIBAYAMA1, E. KOKUBU1, D. KITA2, Y. KIKUCHI1, K. ISHIHARA1
1

Department of Microbiology, Tokyo Dental College, Tokyo, Japan, 2Department of Periodontology, Tokyo Dental College, Tokyo, Japan

Objectives:Capnocytophaga ochracea is a gram-negative rod-shaped bacterium with gliding motility that is a major componentof dental plaque biofilms. It has a type IX secretion system that exports proteins, which have gliding motility-associatedC-terminal domain. Hyalin-like protein, one of the exported proteins, is a large protein proposed to be involved in quorum
sensing according to the Kyoto Encyclopedia of Genes and Genomes, suggesting that this protein may play a role in biofilm
formation. In this study, we aimed to investigate the role of C. ochracea hyalin-like protein in biofilm formation.Methods: Thegene encoding hyalin-like protein and its flanking regions were amplified from C. ochracea ATCC 27872 genomic DNA, followed
by insertion of the ermFermAM cassette into the gene. The resulting fragment was electroporated into C. ochracea ATCC
27872 to inactivate the gene by homologous recombination. The hyalin-like protein-deficient mutant was selected and isolatedusing blood agar plates containing 10 μg/mL erythromycin. The growth rate of the mutant was evaluated by measuring theoptical density at 660 nm. The morphology of the biofilm organized by the mutant was evaluated by confocal laser scanningmicroscopy (CLSM).Results: Insertion of the ermFermAM cassette into the target gene was confirmed by PCR using the genomic
DNA of the hyalin-like protein deficient mutant, WT-1. The growth rate of WT-1 was almost the same as that of the wild-typestrain. The morphology of the WT-1 colony was similar to that of the wild-type strain, but the mutant lost its spreading feature
at the edge of the colony. Observations from CLSM indicated that the biofilm organized by the mutant was sparse comparedwith that organized by the wild-type strain.Conclusions: These data suggest that hyalin-like protein is involved in biofilm
formation by C. ochracea.

─ 88 ─

The periodontopathic bacterium Fusobacterium nucleatum induced proinflammatory cytokine
production by human respiratory epithelial cells and in the lower respiratory organs in mice
K. IMAI1, N. WATANABE1,2, S. YOKOE1,2, S. SATO2
1

Department of Microbiology, Nihon University School of Dentistry, 2Department of Periodontology, Nihon University School of
Dentistry

Poster Presentation

─ 89 ─

Rising Scientist Session

ObjectiveImmunoglobulin A nephropathy (IgAN) is the most frequent type of chronic glomerulonephritis seen worldwide,
though its detailed mechanism remains unclear. Streptococcus mutans strains with cell surface expression of the collagenbinding protein Cnm are frequently detected in the oral cavity of IgAN patients. In the present study, cnm-positive S. mutans
was found to be associated with IgAN in a rat caries model.MethodsSpecific pathogen-free Sprague-Dawley rats (males, 15 daysold) were inoculated once daily for five consecutive days with 100 μl of a cell suspension containing Cnm-positive S. mutans
strain SN74R, isolated from the oral cavity of an IgAN patient. Cnm-negative S. mutans MT8148R, isolated from the oral cavity ofa healthy subject, was administered to control group rats in the same manner. All rats in both groups were provided a powdered
caries-inducing diet ad libitum. At 32 weeks after inoculation, the rats were euthanized under ether anesthesia and caries in
12 molar teeth obtained from each were scored. Compositional analysis of collected urine and fluorescent immunostaining of
kidney tissues were performed using IgA and C3 antibodies. ResultsThe caries score of the Cnm-negative MT8148R group was
significantly higher than that of the Cnm-positive SN74R group (P<0.01). Severe dental caries lesions reaching to the pulp wereobserved in both groups. The positive rate of hematuria in the Cnm-positive SN74R group was significantly greater than that in
the Cnm-negative MT8148R group (P<0.001). Furthermore, immunochemical results demonstrated that the numbers of IgApositive and/or C3-positive sections were significantly greater in the Cnm-positive SN74R group (P<0.05).ConclusionThe present
results suggest that Cnm-positive S. mutans strains associated with severe dental caries can trigger an immune response inboth kidney and non-kidney tissues, resulting in induction of IgAN-like lesions.This study was supported by JSPS KAKENHI grants(17K11959, 18H03010).

Symposium III

Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences,
Okayama, Japan, 2Department of Pediatric Dentistry, Division of Oral Infection and Disease Control, Osaka University Graduate Schoolof Dentistry, Suita, Oska, Japan, 3Division of Nephrology, Seirei Hamamatsu General Hospital, Hamamatsu, Japan, 4Division of Kidney
and Dialysis, Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya, Japan, 5Department of Nephrology anf
Endocrinology, National Defense Medical College, Tokorozawa, Japan

Symposium II

1

Symposium I

IgA Nephropathy-like Lesion Development in Rat Caries Model
S. NAKA1, K. WATO2, T. MISAKI3, Y. NAGASAWA4, S. ITO5, R. NOMURA2, M. MATSUMOTO-NAKANO1, K. NAKANO2Special Lecture032:

Greeting

Introduction
Aspiration pneumonia is a major health problem owing to its high mortality rate in elderly people. The secretion ofproinflammatory cytokines such as IL-8 and IL-6 by respiratory epithelial cells, which is induced by infection of respiratory
bacteria such as Streptococcus pneumoniae (S.p), contributes to the onset of pneumonia. These cytokines thus play a key rolein orchestrating inflammatory responses in the lower respiratory tract. Although emerging evidence has revealed an association
between aspiration pneumonia and periodontitis, how periodontitis contributes to the onset of aspiration pneumonia
remains unclear. Most periodontopathic bacteria are anaerobic and are therefore unlikely to survive in the lower respiratoryorgans of humans. Hence, we aimed to elucidate whether exposure to heat-inactivated periodontopathic bacteria induces
proinflammatory cytokine production by several human respiratory epithelial cells and in the lower respiratory organs andserum in mice.
Materials and Methods
Real-time PCR and ELISA were used to investigate in vitro induction by heat-inactivated periodontopathic bacteria and S.p formRNA expression and protein production of proinflammatory cytokines by human respiratory epithelial cells. ELISA was also
used to determine in vivo induction of cytokine production in the lower respiratory organs and serum of intratracheally heatinactivated Fusobacterium nucleatum (F.n)-inoculated mice.
ResultSome, but not all, periodontopathic bacteria, especially F.n, strongly induced IL-8 and IL-6 production by BEAS-2B bronchial
epithelial cells. In addition, F.n induced IL-8 production by A549 alveolar epithelial cells as well as IL-8 and IL-6 production by
Detroit 562 pharyngeal epithelial cells. Furthermore, F.n induced considerably higher cytokine production than S.p. This was
also observed in the entire lower respiratory organs and serum in mice.
Conclusion
F.n is a powerful inflammatory stimulant for respiratory epithelial cells and can stimulate cytokine production, thereby
potentially contributing to the onset of aspiration pneumonia.

Keynote Lecture

031:

033:

Effects of Helicobacter pylori Infection in Caries-induced Rats
T. KADOTA, Y. OGAYA, R. NOMURA, K. NAKANO
Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Osaka, Japan

Objectives: Helicobacter pylori infection, responsible for gastric disease, is considered to occur via the oral cavity and someepidemiological studies have reported that patients with dental caries are more likely to harbor H. pylori in the stomach. In thepresent study, we investigated the effects of H. pylori infection on dental caries and stomach condition in caries-induced rats.
Methods: Specific-pathogen-free Sprague-Dawley rats (n=28, 18 days old) were divided into 3 groups and fed a caries-inducing
diet containing 56% sucrose throughout the experimental period. Group A (n=10) was inoculated with Streptococcus mutans
strain MT8148R at 1.0×108 CFU for 5 consecutive days from 18 days old to induce dental caries, after which 1.5×106 CFU of H.
pylori strain J99 was administered for 5 consecutive days from 75 days old. Group B (n=10) was only administered S. mutans at
the same timing as Group A, while Group C (n=8) received no bacterial inoculation. All rats were euthanized at 110 days old,and unilateral maxilla and mandibular bones were extirpated. Furthermore, dental caries on occlusal surfaces of molar teeth(6 per rat) were counted by a single dentist. Additionally, stomach tissues were extirpated and stained with hematoxylin andeosin, then deflection of gastric mucosa was scored from 0 to 2 by a single pathologist.Results: The number of dental caries inGroup A was greater than that in Group B and significantly greater as compared to Group C (p<0.01). Histopathological analysis
indicated an average gastric mucosa deflection score in Group A of 1.60, which was significantly higher than that in Group B (0.10)(p<0.001) and Group C (0.63) (p<0.05).Conclusions: The present findings indicate that H. pylori infection in caries-induced rats
induces dental caries with greater severity and deflection of gastric mucosa.This study was supported by a JSPS KAKENHI grant (JP18K17252).

034:

Prevalence of Specific Streptococcus mutans Harbored by Non-alcoholic Steatohepatitis Patients
K. TABATA1, S. NAKA1, S. TONOMURA2,3,4, K. NAKANO5, M. MATSUMOTO-NAKANO1
1

Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Japan,
Department of Neurology, Nara City Hospital, Japan, 3Department of Neurology, National Cerebral and Cardiovascular Center, Japan,
4
Department of Neurology, Graduate School of Medicine and Faculty of Medicine, Kyoto University, Japan, 5Department of Pediatric
Dentistry, Division of Oral Infection and Disease Control, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan
2

ObjectiveIn our previous studies, cell surface collagen-binding protein (Cnm)- and 190-kDa cell surface protein antigen (PA)positive Streptococcus mutans strains were shown to induce non-alcoholic steatohepatitis (NASH) aggravation. Here, we
assessed saliva samples obtained from nonalcoholic fatty liver disease (NAFLD) patients, including those with NASH and nonalcoholic fatty liver (NAFL), to determine the prevalence of Cnm-and PA-positive S. mutans strains, as well as their biological
functions. MethodsAfter receiving informed consent for participation, saliva specimens were collected from 40 biopsy-proven
NAFLD patients (20 with NASH, 20 with NAFL). Specimens were serially diluted and plated in Mitis-Salivarius agar containing
bacitracin, then the number of colonies was determined. Genomic DNA was extracted from S. mutans organisms isolated fromthe plates, then PCR was performed to detect the cnmgene encoding Cnm, while PA expression was confirmed by western
blotting. Collagen binding ability of the bacterial strains was determined using type IV collagen. ResultsThe number of S.
mutans in saliva specimens from NASH patients was significantly higher (P<0.05), and the percentage of those with NASH
who possessed Cnm- and PA-positive strains significantly greater (P<0.05), as compared to specimens from NAFL patients. In
addition, the type IV binding ability of strains possessed by the NASH patients was significantly greater as compared to the
NAFL patients (P<0.05). On the other hand, the number of platelets and adiponectin level were significantly lower in NAFLD
patients with Cnm- and PA-positive S. mutans (P<0.05) as compared to NAFLD patients with S. mutans negative for both.
Similarly, adiponectin level was significantly higher in NASH patients with Cnm- and PA-positive S. mutans as compared to NASH
patients with S. mutans negative for both (P<0.05). ConclusionCnm- and PA-positive S. mutans strains were frequently detectedin NASH patients saliva samples, suggesting that those specific strains are associated with NASH aggravation.

─ 90 ─

The Initiation and development of oral microbiome formation in Japanese healthy infants
A. SAKURAI, H. HOMMA, N. NAGAI, T. OTA, S. SHINTANI
Department of Pediatric Dentistry, Tokyo Dental College, Tokyo, Japan

Greeting
Special Lecture

Objectives: With the advent of next-generation gene sequencing, recent studies have advanced current knowledge regarding
the microbiota formed in various tissues and organs of the human body. However, few studies have investigated changes in the
microbiota of the same infants over a long period of time. The aim of this study is to elucidate how the intraoral microbiota isestablished in newborns.Methods: The present study was performed following the approval of the Ethics Committee of ourcollege. Saliva and tongue-swab samples of 5 infants had been collected on the day of birth, then at 1 week, 1, 3, 6, and 9months, and 1 year after birth, and then every 6 months afterwards. Specimens were also collected from their parents when
the subjects were 1 year old. Microbiome analysis of the V3-V4 region of bacterial 16S rRNA was performed and sequencereads matching the reference sequence on SILVA database were explored to estimate the lowest possible class. In regard to therichness and diversity of microbiomes, the observed OTUs and Shannon Index were calculated and compared among samples.
Results: The relative abundances of Streptococcus were remarkably high in samples collected immediately after birth, butwere decreased gradually. On the other hand, the relative abundance of Haemophilus and Rothia was significantly higher at
2 years of age than at birth in lingual swab specimens. It is noteworthy that a PCoA plot and phylogram based on unweighed
Unifrac distance showed that the microbiota was evidently diverted in first 2 year of life. No significant difference was observed
between the 2-year-olds and adults in regard to the microbiota at genus level.Conclusions: From our findings, lifestyle anddietary habits from birth to 2 years may exert great effects on the risk of dental caries, periodontal disease, and diseases
assocated with the oral microbiota in later life.

Keynote Lecture035:

Symposium I

Omics analysis defines differences in microbial community structure between peri-implantitis andperiodontitis
K. KOMATSU1, Y. TAKEUCHI1, T. SHIBA1, T. WATANABE2, M. SHIMOGISHI3, M. SHIBASAKI3, T. NEMOTO1, T. KOYANAGI1, S.
KATAGIRI1, T. IWATA1
1

Department of Periodontology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan,
Department of Chemistry, Nihon University School of Dentistry, Tokyo, Japan, 3Department of Oral Implantology and Regenerative
Dental Medicine, Tokyo Medical and Dental University, Tokyo, Japan

Symposium II

036:

2

Rising Scientist Session
Poster Presentation

─ 91 ─

Symposium III

Objectives
Peri-implantitis shows faster progression and less responsiveness to conventional periodontal treatment than periodontitis. This
study aimed to reveal that disease-specific species and transcriptional activity lead to disease-specific clinical features using an
integrated 16S rDNA sequencing, metagenomic, metatranscriptomic, and network analysis.
Methods
Subgingival plaque samples were collected from 23 subjects with both peri-implantitis and periodontitis sites. Microbial DNA
was extracted from each plaque sample and evaluated for microbial species and gene composition by 16S rDNA sequencing
and metagenomic analysis. Metatranscriptomic data that we previously reported was also used to evaluate active species
and gene activities. The sequences of 16S rRNA region were assigned to the Human Oral Microbiome Database to identify
the taxonomic profile. The sequences of mRNA region were assigned to several virulence factor databases, non-redundantsequencing database, and pathway database to identify the microbial function of each disease. The activities of each species
and gene were calculated by the comparison of read abundances based on DNA and RNA. The correlations based on the readabundance between each species were evaluated by the sparse correlations for compositional data algorithm program. The
microbial co-occurrence networks of peri-implantitis and periodontitis were visualized with Cytoscape.
Results
The highly active species were Peptostreptococcus stomatis and Solobacterium moorei in peri-implantitis, and Fusobacterium
nucleatum subsp. vincentii and Peptostreptococcus stomatis in periodontitis, respectively. The microbial co-occurrence network
revealed Prevotella denticola and Solobacterium moorei had high activity and were significantly correlated in peri-implantitis,whereas none of the species showed significant correlation in periodontitis. Linear discriminant analysis effect size indicatedthat plr/gapA genes which were microbial virulence factors were significantly enriched in peri-implantitis.
Conclusion
Prevotella denticola and Solobacterium moorei were identified as core species specific to peri-implantitis. In addition, plr/
gapA genes were putative virulence factors related to the cause of faster disease progression in peri-implantitis than that inperiodontitis.

037:

Periodontal Bacteria Distribution in Child with Early Primary Tooth Loss
Y. MIYAI, S. NAKA, M. MATSUMOTO-NAKANOOkayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan

ObjectiveChildren with early primary tooth loss often have a genetic disease or chromosomal abnormality, which rarely occur
in those with no systemic disorder. Periodontal disease with loss of teeth is known to be associated with the presence ofsubgingival periodontopathic bacteria. In this study, a child with subgingival periodontopathic bacteria but no systemic disorder
who showed early primary tooth loss is reported.MethodsA 7-year-old girl was referred to our clinic with severe mobilityof multiple teeth. Gingival crevicular fluid (GCF) had been collected from the deepest pockets of both the patient and hermother with paper points. Bacterial DNA was extracted from those specimens and PCR analyses performed for detection of
10 major periodontal pathogens using specific primers. After culturing the samples in blood agar medium, isolated colonies
were identified using sequence analysis. ResultsPeriodontal pockets for most mandibular teeth in the patients were 4 mm or
greater. Periapical radiography revealed prominent vertical bone resorption in the left first and second primary molar areas.
Blood test results supported findings of a systemic inflammatory condition, though no immunological abnormality was seen.
PCR analyses of specimens from child and mother detected seven periodontal pathogens in both, Porphyromonas gingivalis,
Tannerella forsythia, Prevotella nigrescens, Campylobacter rectus, Aggregatibacter actinomycetemcomitans, Capnocytophaga
ochracea, and Capnocytophaga sputigena, with 2 additional species detected in the mother. Among the isolated bacteria, weobserved orange complex (Prevotella intermedia, Campylobacter gracilis, Streptococcus constellatus; 36.6%), green complex (C.
sputigena; 3.3%), yellow complex (Streptococcus mitis, Streptococcus anginosus; 36.6%), blue complex (Actinomyces naeslundii;
20.0%), and purple complex (Veillonella parvula; 3.3%) species.ConclusionThese results suggest that premature tooth loss
is related to growth of orange complex periodontopathic bacteria. In addition, mother-to-child transmission of periodontal
pathogens is a possible factor for the onset and development of aggressive periodontitis identified in this case.

038:

CTLA-4 Reduces Bone Resorption Through the Inhibition of Osteoclast Differentiation
S. NAKANE1, K. IMAMURA1, K. ISHIHARA2,3, A. SAITO1,2
1

Department of Periodontology, Tokyo Dental College, Tokyo, Japan, 2Oral Health Science Center, Tokyo Dental College, Tokyo, Japan,
Department of Microbiology, Tokyo Dental College, Tokyo, Japan

3

Objectives: Cytotoxic T lymphocyte associated antigen-4 (CTLA-4) is one of the immune checkpoint receptors expressed on
the surface of T cells. It has been reported that CTLA-4 administration suppresses bone resorption as well as inflammation inarthritis model mice. However, information is limited on the effects of CTLA-4 on alveolar bone. The purpose of this study is toinvestigate the role of CTLA-4 on bone resorption in periodontitis.
Methods: Periodontitis was induced by placing silk ligature on the second molar of C57BL/6 mice. To investigate the effects of
CTLA-4, CTLA-4 immunoglobulin fusion protein (CTLA-4-Ig) was administered intraperitoneally. The effect of CTLA-4 on alveolarbone resorption was evaluated by μCT and H-E staining, and the effect on osteoclast differentiation was evaluated by TRAP
staining. In vitro, RAW 264.7 cells were treated with RANKL and CTLA-4-Ig and the number of osteoclast-like cells was counted.
The expression levels of osteoclast differentiation markers (C-fms, Carbonic anhydrase II, and Cathepsin K) and signaling
molecule downstream of CTLA-4 (PP2A) were assessed by qRT-PCR.
Results: CTLA-4 (50 μg/kg) significantly suppressed alveolar bone resorption (65% on the buccal side and 47% on the palateside, p<0.01) and decreased the number of TRAP-positive osteoclast-like cells (53%, p<0.05) in periodontitis model mice. In
vitro, the treatment with CTLA-4 (300 μg/ml) significantly decreased the mRNA expression of C-fms, CaII, and Cat-k (77%, 69%
and 41%, respectively, p<0.001) and the prevalence of osteoclast-like cells (36%, p<0.001), when compared to the RANKLtreated control. The expression level of PP2A was increased (1.4-fold, p<0.01) by the treatment with CTLA-4 (300 μg/ml).
Conclusion: It is suggested that CTLA-4 reduces alveolar bone resorption through the inhibition of osteoclast differentiation via
activation of PP2A at the site of periodontitis.

─ 92 ─

An immunohistochemical study on the expression of bioactive molecules in the mouse kidney in P.
gingivalis LPS-induced diabetic nephropathy
K. KOICHIRO1, Y. SAWA2, T. FUJITA1, S. TAMAOKI1
1

Section of orthodontics Department of Oral Growth & Development, Division of Clinical Dentistry, Fukuoka Dental College,
Deparment of Oral Function & Anatomy, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences2

Greeting
Special Lecture

Diabetic nephropathy is a serious complication of diabetes mellitus, which is caused by glomerulosclerosis with renal failure
based on the dysfunction of glomerular capillaries. We recently reported that the glomerular endothelium in the glomeruli
of diabetic mice expresses toll-like receptor (TLR)2 and TLR4, and that Porphyromonas (P.) gingivalis lipopolysaccharide (LPS)
induces diabetic nephropathy with urinary protein and the accumulation of type 1 collagen, IL-6, TNF-α, and TGF-β in glomeruli.
This study aims to immunohistochemically investigate the expression of leukocyte adhesion molecules, and renal physiologically
active molecule FGF23 and SARS-CoV-2 receptor ACE2 in the glomeruli of P. gingivalis LPS induced-diabetic nephropathy model
mouse. All of the diabetic mice subjected to repeated P. gingivalis LPS administrations were euthanized within the survival
period of all diabetic mice not administered LPS and within the survival period of all of the LPS-administered non-diabetic
mice. The VCAM-1, E-selectin, FGF23, and ACE2 were overexpressed in the glomeruli of P. gingivalis LPS induced-diabetic
nephropathy in mice although these molecules were not found in LPS-administered normal kidney and non LPS-administereddiabetic mice. It is thought that the P. gingivalis is one of the critical factors in the diabetic patients.

Keynote Lecture039:

Symposium I

Artepillin C regulates extracellular matrix gene expressions in human periodontal fibroblasts by DNA
methylation
R. TAKAI1, O. UEHARA2, T. MORIKAWA3, K. YOSHIDA3, J. SATO3, Y. ABIKO3, T. OHTA1
1
Advanced Research Promotion Center, Health Sciences University of Hokkaido, Hokkaido, Japan, 2Division of Disease Control andMolecular Epidemiology, Health Sciences University of Hokkaido, Hokkaido, Japan, 3Division of Oral Medicine and Pathology, Health
Sciences University of Hokkaido, Hokkaido, Japan

Rising Scientist Session
Poster Presentation

─ 93 ─

Symposium III

Objectives:
Artepillin C is the major component in Brazilian green propolis. As propolis exhibits antibacterial, antifungal, and antiviralproperties, it is often used for the prevention of periodontal diseases. However, the mechanism through which propolis affects
the periodontal tissue is still unknown. To elucidate the effect of artepillin C on periodontal tissue, we analyzed the expression
level and DNA methylation status in human periodontal ligament fibroblasts (HPDLFs) upon artepillin C treatment.
Methods:
The culture of HPDLFs was repeated alternating 3 days with artepillin C (25 μM/ml, WAKO) and 3 days without artepillin C in
DMEM containing 10% FBS for 1 month. Untreated samples were used as controls. We then performed microarray (Agilent
technology) and quantitative RT-PCR analyses. The expression profile of the genes analyzed through microarray was classified
by functional annotation with keyword analysis in Database for Annotation, Visualization, and Integrated Discovery (DAVID). The
selected relevant genes were further analyzed for their DNA methylation status in the promoter regions through methylationspecific PCR.
Results:
Overall, 370 (1.5-fold) upregulated genes and 377 (0.66-fold) downregulated genes were identified upon artepillin C treatment
via microarray analysis. Among these, 18 genes belonging to the extracellular matrix were significantly correlated in the
keyword analysis in DAVID. Within the extracellular matrix genes, HSPG2 and COL5A3 exhibited significantly altered gene
expression patterns and DNA methylation levels.
Conclusions:
These results indicate that artepillin C is responsible for the altered methylation status in the promoter region, resulting indifferences in the expression patterns of the extracellular matrix-related genes.

Symposium II

040:

041:

Exosomes from human gingiva-derived MSCs inhibit periodontal bone loss
Y. NAKAO, T. FUKUDA, Y. WATANABE, C. HAYASHI, K. KAWAKAMI, M. TOYODA, H. YAMATO, T. SINJO, U. TANAKA, T.
SANUI, F. NISHIMURA
Department of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan

Objectives: MSCs are known to exhibit anti-inflammatory function besides its multipotency. MSCs from gingiva (GMSCs)
are easier to isolate, and appear to secret higher amounts of exosome than other MSCs. Our previous study demonstrated
that exosomes from gingiva-derived MSCs (GMSCs) were capable of accelerating wound healing capacity by inducing antiinflammatory (M2) macrophage polarization, and TNF-α preconditioning further enhanced these effects. In this study, tofurther gain insight into GMSC-based tissue regeneration, we examined the preventive effect of TNF-α preconditioned-GMSCderived exosomes against periodontal bone loss and underlying molecular mechanisms.MethodsGMSCs were isolated fromhuman gingival tissues under the approved Institutional Review Board (IRB) protocol at Kyushu University Hospital (2019-374).
GMSC-derived exosomes were isolated from the serum-free conditioned media using the MagCapture Exosome Isolation Kit
PS. The effect of GMSC-derived exosomes on inflammatory bone loss were examined by ligature-induced periodontitis modelin mice under an institutionally approved animal research protocol (Kyushu University, A21-044-1). TNF-α inducible exosomal
miRNAs were analyzed by miRNA microarray, and the mechanisms by which inhibitory effect of RANKL expression induced
by exosomal miRNA was investigated in LPS-stimulated periodontal ligament cells.ResultsLocal injection of GMSCs-derived
exosomes significantly reduced periodontal bone resorption and the number of TRAP-positive osteoclasts in mice, and theseeffects were further enhanced by preconditioning of GMSCs with TNF-α. GMSCs-derived exosomes reduced expression of
RANKL mRNA in mice gingival tissue, while the expression of OPG mRNA was significantly up-regulated. Microarray analysis
identified that miR-1260b was one of the most highly up-regulated miRNAs by TNF-α-preconditioning. RANKL expression was
regulated by Wnt5a in PDLCs, and exosomal miR-1260b was found to be essential for the inhibition of osteoclastogenesis bytargeting the Wnt5a-mediated RANKL pathway.ConclusionsBesides its anti-inflammatory effect, exosomes from TNF-α-treated
GMSCs directly prevent periodontal bone loss via miR-1260b-mediated inhibition of osteoclastgenesis.

042:

PPARγ is required for periodontal ligament cells to retain cemento/osteogeneity
H. YUAN1, S. SUZUKI1, A. SATO1, T. YAMAMOTO1, E. NEMOTO1, M. SAITO2, S. YAMADA1
1

The Department of Periodontology and Endodontology, Tohoku University school of Dentistry, 2The Department of Operative
Dentistry, Tohoku University school of Dentistry

Objective: Periodontal ligament tissue acts as a principle cell reservoir when periodontal regeneration therapy has been
conducted. Periodontal ligament (PDL) cells actively express osteogenic genes in vitro and in vivo. Thus far, accumulating
articles disclose the importance of cell-matrix connection, ligand binding to plasma membrane receptors, and extracellular
cellular matrix stiffness, which directly controls the fate and differentiation stage of PDL cells. Recently, intermediate productsof biochemical reactions such as TCA cycle, fatty acid β-oxidation, and respiratory chain have been identified as modulator ofcellular differentiation. However, it is still unclear whether metabolic pathways involve in the retention of osteogenic capacities
in PDL cells. Here, we explore the roles of PPARγ, a nuclear receptor and takes pivotal roles in regulating energy metabolism,
for osteogenic capacities of PDL cells.Materials and methods: PPARγ expression was suppressed by 5 independent siRNAs inhuman PDL (hPDL) cells. hPDL cells were cultured in mineralization induce medium (ascorbic acid and β-glycerophosphate)and cementogenic/osteogenic differentiation was assessed by ALP activity and calcium deposition identified by alizarin red S
staining. RNA and anti-PPARγ precipitated chromatin were obtained from siRNA-transfected hPDL cells for RNA-seq and ChIPseq analyses, respectively.Results: Suppression of PPARγ expression induced decreased ALP activity and suppressed calcium
deposition compared with control siRNA-transfected cells. Gene Ontology analyses of RNA-seq revealed that suppressed PPARγ
resulted in down-regulation of the genes associated with osteogenic differentiation and metabolic process and up-regulationof the genes associated with inflammatory responses. ChIP-seq disclosed PPARγ binding to known target sites adjacent tometabolic gene loci, however local chromatin area close to osteogenic gene loci was not enriched. Conclusion: PPARγ is
indispensable for hPDL cells to possess osteogenic capacities and PPARγ might indirectly regulate osteogenic gene expression
possibly through modulating metabolic pathways and their intermediate products.

─ 94 ─

Role of IQGAP1- Flightless I interaction in collagen remodeling by fibroblast
K. NAKAJIMA1, P. ARORA2, C. MCCULLOCH2
1

Department of Pathology, Tokyo Dental College, Tokyo, Japan, 2Faculty of Dentistry, University of Toronto, Toronto, ON, Canada

Greeting
Special Lecture

Objectives: Periodontal connective tissue matrices undergo continuous remodeling to maintain homeostasis. Physiologicalremodeling is dependent on the degradation of collagen fibers and the phagocytic pathway. A multidomain, small GTPase
activating protein IQGAP1 is thought to be involved in the generation of cell extensions through the interaction of cdc42 andthe actin binding protein Flightless I (FliI). Here we examined the effect of IQGAP1-Flightless I interaction in collagen remodelingthrough its impact on the generation of cell extensions and in collagen phagocytosis.Methods: Human gingival fibroblasts(HGFs), IQGAP1+/+ and IQGAP1-/- mouse embryonic fibroblasts were examined by immunoblotting, immunostaining andimmunoprecipitation. Collagen-coated beads were used for immunostaining and collagen internalization assay. For the collagendegradation assay, cells cultured in three dimensions on collagen gel were used. Stained cells were observed by confocal
microscopy and quantified.Results: IQGAP1 was strongly expressed by HGFs and was localized to vinculin-stained cell adhesions
and sites where cell extensions were initiated, which were co-localized with FliI. Immunoprecipitation showed that IQGAP1
associated with FliI. HGFs showed 10-fold increases of collagen binding, 6-fold higher internalization, and 3-fold higher β1
integrin activation between 30 and 180 min after incubation with collagen. Compared with IQGAP1+/+ fibroblasts, deletionof IQGAP1 reduced collagen binding (1.4-fold), collagen internalization (3-fold), β1 integrin activation (2-fold), and collagendegradation (1.8-fold).Conclusions: We conclude that IQGAP1 affects collagen remodeling through its regulation of phagocytic
degradation pathways of fibroblast, which may involve the interaction of IQGAP1 with FliI.

Keynote Lecture043:

Symposium I

Amelogenin down-regulates MHC class II antigen presentation on macrophages.
K. YOTSUMOTO, T. SANUI, H. YAMATO, U. TANAKA, Y. NAKAO, Y. WATANABE, C. HAYASHI, T. FUKUDA, F. NISHIMURA
Department of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan

Rising Scientist Session
Poster Presentation

─ 95 ─

Symposium III

Enamel matrix derivatives (EMDs)-based regenerative therapy is suggested to promote better healing with minimal
inflammatory response after periodontal surgery. We previously found stimulation of monocytes with amelogenin suppresses
major histocompatibility complex class II (MHC II) gene expression using microarray analysis. However, the detailed molecularmechanisms for this process remain unclear. Here, we aimed to understand the underlying mechanism and its effects on
immune system.THP-1 monocytic cells were stimulated with 50 μM PMA. The cells were pretreated with 10 μg/ml amelogenin
for 24 hours, followed by the stimulation with 2.5 μg/ml IFNγ for 24 hours. The cell surface expression of antigens wasevaluated by flow cytometry, and signal transduction pathway was analyzed by real-time PCR and western blotting. Cellular
uptake of amelogenin was observed by using confocal laser microscopy. Histone modification of class II transactivator (CIITA)
promoter region was analyzed by chromatin immunoprecipitation. T cell activation was evaluated by mixed leukocyte reaction(MLR). Amelogenin down-modulated IFNγ-induced cell surface expression of MHC II and this effect was widely conserved
across species, as similar effect was confirmed in raw 264.7 murine macrophages. Ameloginin accumulated in the nucleus asearly as 15 min following stimulation and inhibited subsequent CIITA expression. Reduced MHC II expression on macrophages
pretreated with amelogenin down-regulated the expression of T cell activation markers CD25 and CD69, T cell proliferation,and IL-2 production by allogenic CD4+ T lymphocytes in MLR. H3K27ac and H3K4me3 in CIITA promoter IV region, which areessential for conversion to euchromatin, were markedly suppressed by amelogenin.Amelogenin suppresses MHC II expression
by altering chromatin structure and inhibiting CIITA promoter IV transcription activity and attenuates subsequent T cell
activation. Therefore, clinically observed better wound healing after the surgery may be, at least in part, explained by themechanism elucidated in the current study.

Symposium II

044:

045:

Adipose specific C-C motif chemokine ligand (CCL) 19 overexpression drives the mice to both insulin
resistance and weight gain.
M. HAYASHI, M. IWASHITA, Y. NISHIMURA, T. SHINJO, T. ZEZE, T. SANO, A. YAMASHITA, F. NISHIMURA
Department of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University

Objectives: The pathophysiological features of overweight and/or obesity are adipose tissue inflammation and infiltration ofactivated immune cells, such as macrophages. This results in the increased production of adipokines secreted by adipocytes,
as well as additional inflammatory cytokines and chemokines. We previously reported that co-culture of adipocytes andendotoxin-stimulated macrophages significantly increases the expression of C-C motif ligand 19 (CCL19), suggesting that
periodontal bacteria-activated circulating monocytic cells may further enhance adipose tissue inflammation upon migration into
adipose tissue via its receptor, C-C chemokine receptor type 7 (CCR7). Here, we investigated the effects of CCL19/CCR7 pathway
on subsequent metabolic disorders potentially enhanced by periodontal inflammation.MethodsAdipocyte-specific Ccl19 knockin (KI) mice were generated, and the mice were fed either a normal diet or 40% or 60% fat-diet (FD) to investigate the effects of
CCL19 on the induction of inflammation and lipid metabolism.ResultsCcl19 KI mice exhibited increased inflammatory signs in
the adipose tissues and enlarged subcutaneous white and brown adipose tissue as compared with wild-type (WT) mice. Ccl19
KI mice were characterized by increased extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation and decreased
AMP-activated protein kinase α (AMPKα) phosphorylation in the adipose tissue. Peroxisome proliferators-activated receptor
γ coactivator 1α (PGC1α) and uncoupling protein 1 (UCP1) protein expression was significantly reduced in brown adipose
tissue of Ccl19 KI mice compared to that in WT mice. These changes were most marked when KI mice were fed a 40% FD,
which resembled western style diet. ConclusionsActivation of CCL19/CCR7 pathway in adipose tissue inhibited AMPKα throughactivating ERK1/2, resulting in impaired lipid metabolism and energy regulation. Thus, subjects preferring western style diet,when accompanied by severe periodontal disease, may suffer from resistance to diet.

046:

Characterization of the PLAP-1-GFP/CreER knock-in mouse
T. IWAYAMA1, K. TOMITA1, S. MATSUMOTO1, M. IWASHITA1, C. FUJIHARA1, M. TAKEDACHI1, S. YAMADA2, S. MURAKAMI1
1

Department of Periodontology, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan, 2Department of Periodontology
and Endodontology, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan

Objectives:
Periodontal ligament (PDL) is the fibrous connective tissue between the alveolar bone and cementum. The function of PDL
cells was studied extensively in vitro, however, the molecular regulations for homeostasis of PDL in vivo remain elucidative.
The inducible Cre-lox system is a valuable tool to study the regulation of the tissue homeostasis in a spatial and time-restrictedfashion. We have previously found that PLAP-1/Aspn is highly and specifically expressed in PDL. In this study, we aimed togenerate and characterize a mouse line that expresses both green fluorescent protein (GFP) and tamoxifen-inducible Cre
recombinase from endogenous PLAP-1 locus.
Methods:
A targeting construct was created that inserts the CreERT2-2A-EGFP-WPRE cassette into the endogenous start codon of the
PLAP-1 gene. The construct was electroporated into C57BL/6 embryonic stem (ES) cells, and correctly targeted ES cells were
injected into C57BL/6 blastocysts, which were implanted into pseudo-pregnant females. The resulting chimeric mice were bredwith C57BL/6, and offspring were analyzed. EGFP expression in periodontal tissue was compared with PLAP-1 endogenous
mRNA expression by RNAscope in situ hybridization. Further, the knock-in mice were crossed with Rosa26-tdTomato Cre
reporter mice to label PLAP-1 lineage cells. After the development of the periodontium was completed, the mice are treatedwith Tamoxifen.
Results:
Newly established PLAP-1-GFP/CreER knock-in mouse expressed GFP in most spindle-shaped fibroblastic cells but not in
osteoblasts, cementoblasts, and blood vessels in PDL. These signals were matched to in situ expressions of PLAP-1 mRNA
expression. Upon crossing with Cre reporter mice and 3-day after tamoxifen treatment, tdTomato expression was matched to
GFP expression.
Conclusions:
The fluorescent reporter and lineage tracing analysis showed faithful expression of GFP/CreER under the PLAP-1 promoter inthe knock-in mouse. This method can be a valuable tool to i) trace the fate of PDL cells in vivo by crossing with Cre reporter,ii) study gene functions in PDL by crossing with mice with the floxed allele of the targeted gene, and iii) isolate pure PDL cells
according to their GFP expression.

─ 96 ─

Salivary Alpha-Amylase as a stress marker during dental implant surgeries
A. A. Sabbagh, H. Nakata, A. Abdou, K. Shohei, S. Kuroda
Tokyo medical and Dental University, Tokyo, JAPAN

Greeting
Special Lecture

Objectives: The activity of salivary Alpha-Amylase (sAA) has been thought of as an indicator of mental stress. However, it has
not been studied the relationship between sAA levels and mental stress of patients during dental implant treatment. In thepresent study, we examined the correlation between sAA levels and vital signs changes of the patient during dental implant
surgeries.Methods: The total number of patients examined in this study was 44 including 19 for installing dental implants, 22
for second surgery, and 3 for connective tissue graft (17 males and 27 females). Saliva samples were collected before and after
surgery to evaluate sAA levels. The heart rate and blood pressure were measured at 3 time points: before, during and after
the implant surgery. Data were collected and the correlation between sAA and vital signs were statistically analyzed (α=0.05).
Results: Nine patients had high levels in both sAA activity and blood pressure (6 for installing implants and 3 for second
surgery) while 19 patients had normal sAA activity but high blood pressure (7 for installing implants and 12 for second surgery).
Additionally, 19 patients had high sAA activity but normal blood pressure after surgery. Eight patients had normal BP andsAA. Statistically there is no significant correlation between blood pressure and sAA activity levels before surgery (rs=-0.012,
p=0.951) and after surgery (rs=-0.019, p=0.640).Conclusions: sAA activity tend to increase in the after surgery together with thepatient’s stress level.

Keynote Lecture047:

Symposium I

Regional differences in the density of Langerhans cells, CD8-positive T lymphocytes and CD68-positive
macrophages
Y. OMINE
Iryouhoujin Syuuyuu-kai, Tsuchiura, Japan

Rising Scientist Session
Poster Presentation

─ 97 ─

Symposium III

To provide a better understanding of the local immune system in the face and external genitalia, i.e., the oral floor, lower lip,
palpebral conjunctiva, anus and penis, we examined the distribution and density of CD1a-positve Langerhans cells, CD8-positive
suppressor T lymphocytes and CD68-positive macrophages using specimens from 8 male elderly cadavers.We examinedthe distribution and density of CD1a-positve Langerhans cells, CD8-positive suppressor T lymphocytes and CD68-positive
macrophages using specimens.Most sections were stained with hematoxylin and eosin (H&E), whereas others were used for
immunohistochemistry. The primary antibodies used were (1) mouse monoclonal anti-human CD1a (1:100, Dako N1616, Dako,
Glostrup, Denmark); (2) mouse monoclonal anti-human CD8 (1:100, Dako N1592); and (3) mouse monoclonal anti-human CD68
KP1 (1:100, Dako M0814). Pretreatment autoclaving was conducted in accordance with the manufacturer's instructions. The
secondary antibody (Dako Chem Mate Envison Kit, Dako) was labeled with horseradish peroxidase (HRP), and antigen-antibody
reactions were detected via the HRP-catalyzed reaction with diaminobenzidine.Observations and photography were performed
using a Nikon Eclipse 80 (Nikon, Tokyo, Japan). The field corresponding to a circle 0.8 mm in diameter contained an almost
1-mm surface length of slightly curved epithelium.The density of suppressor lymphocytes showed a significant correlation
between the oral floor and the lip (r=0.78).In addition, the density of either suppressor lymphocytes or macrophages showed
a weak correlation between the conjunctiva and the penis (r=0.59). At each of the five sites, there was no evident correlation
between the density of Langerhans cells and that of coexisting macrophages or suppressor T lymphocytes.The present
observations suggest that the local immune response is highly site-dependent, with a tendency for tolerance rather thanrejection.This study was received December 01, 2014; and accepted in August 19, 2015, Anatomy & Cell Biology. In 2018,
Japanese article was accepted in the journal of the Tokyo Dental College Society (No.118). The research was also presented in
23rd Japanese Academy of MaxilloFacial Implants, Dec.2019.

Symposium II

048:

049:

Delayed Wound Healing after Tooth Extraction under Malnutrition
Y. ZHANG1, H. IDEGUCHI1, H. AOYAGI1, K. YAMASHIRO1, T. YAMAMOTO1, M. NISHIBORI2, S. TAKASHIBA1
1
Department of Pathophysiology - Periodontal Science, Okayama University Graduate School of Medicine, Dentistry andPharmaceutical Science, Okayama, Japan, 2Department of Pharmacology, Okayama University Graduate School of Medicine, Dentistry
and Pharmaceutical Science, Okayama, Japan

Objectives: Malnutrition causes delay in wound healing after tooth extraction. Children in developing country and elderlies
even in developed country have risk of this situation. However, it is unclear how inflammation and malnutrition relate eachother. High mobility group box-1 protein (HMGB1) is one of the damage-associated molecular patterns, which stimulate
inflammasome, then inducing inflammatory response such as secretion of cytokine interleukin-1Β (IL-1Β). This is an essential
response to initiate wound healing. We hypothesized that malnutrition may interfere this cascade, causing abnormal
inflammation and ultimately delaying wound healing.
Methods: We employed tooth-extracted mice under malnutrition condition by low-casein diet by comparing to normal dietfed mice. Malnutrition condition was confirmed by observing weight and triglyceride, albumin, glucose, and total cholesterol inserum after 14-days feeding. In the tooth-extracted socket after 3 and 7 days, the wound tissue was observed by hematoxylineosin staining, and analyzed several factors in inflammation-regeneration lineage such as IL-1Β and other inflammatory andregenerative related cytokines, mesenchymal stem cells and Th2 cells, myeloperoxidase activity, HMGB1, and ATP, by using RTqPCR, flow cytometry, in vivo molecular imaging analysis system, ELISA, immunohistochemistry, and ATP-dependent glycerol-3phosphate generation, respectively.
Results & Discussion: Under the malnutrition condition, delayed wound healing was observed with decrease of mRNA
accumulation of cytokines for regeneration and stem cells accumulation. Myeloperoxidase and mRNA accumulation of IL1Β were decreased at Day3, but obviously increased at Day7. ATP increased at Day7 than Day3. The accumulation of Th2 cells
increased at Day3. HMGB1 increased significantly at Day7. We speculate that in the early stage of inflammation, less ATP andTh2 cells accumulation inhibit the secretion of IL-1Β. While in the later stage, the up-regulation of ATP and the significant
increase of HMGB1 promote the secretion of IL-1Β, which may interfere inflammation resolution and wound healing.
Conclusion: These results suggest that malnutrition alters HMGB1-related inflammation associated with delayed wound healing
after tooth extraction.

050:

Assessment of Facial Changes after Orthognathic Surgery Using Geometric Morphometrics
S. AL BOUGHA1, H. NAKANO2, K. YASUDA1, T. YAMADA1, I. TAKAHASHI3, Y. MORI1
1

Section of Oral and Maxillofacial Surgery-Division of Maxillofacial Diagnostic and Surgical Science - Faculty of Dental Science, Kyushu
University, 2Department of Dentistry and Oral Surgery, Division of Medicine for Function and Morphology of Sensory Organs, Faculty of
Medicine, Osaka Medical College, 3Department of Orthodontics, Faculty of Dental Science, Kyushu University

Objectives:Orthognathic surgery results in significant changes in facial profile. Assessment of these changes is difficult due tointer-individual morphological variations. Therefore, Geometric morphometrics is a powerful tool to isolate surgery-inducedchanges from the normal variation among patients. Our aim in this research is to evaluate changes of the facial soft tissue after
orthognathic surgery using geometric morphometrics analysis.Materials & Methods:This study included twenty-seven patients
who underwent bilateral sagittal split ramus osteotomy (BSSRO), as a set back surgery. Two CT images were taken from eachpatient, the first was before surgery (T0), and the second was six months after surgery (T1). Twenty-seven CT images fromvolunteers with Skeletal Class I were also taken as the control. Three dimensional models were created in 3D modelling software(Mimics; Materialize). These models were imported into 3D surface analyzing software (HBM-Rugle; Medic Engineering)to perform geometric morphometrics analysis and conduct principal component analysis (PCA). PCA measurements werecompared using ANOVA test as a statistical analysis.Result:Among fifteen principle components, there were significant
differences between T0, T1 and control at the first and second principal components. The first principal component represented
a variation in the lower anterior facial height, while the second principal component represented a variation in the anteriorposterior position of chin. The comparison between preoperative group and postoperative group clearly illustrated significant
surgical effect of BSSRO among patients with Skeletal Class III. This effect is demonstrated by decrease of lower facial height,
and movement of chin and lower lip area toward backward. The surgical effect of BSSRO was suboptimal when postoperative
group was compared with control group.Conclusion: Although the patients who underwent BSSRO had significant improvementin the facial profile after surgery, the geometric morphometric analysis detected that additional procedures can be considered
to obtain the optimal facial profile.

─ 98 ─

Metformin inhibits oral cancer cell growth by altering glucose metabolism
S. LIU1, J. WASHIO1, N. TAKAHASHI1
1

Division of Oral Ecology and Biochemistry, Department of Oral Biology, Tohoku University Graduate School of Dentistry, Sendai, Japan,
Department of Head and Neck Oncology, West China Hospital of Stomatology Sichuan University, Chengdu, China

2

Health Sciences University of Hokkaido

Symposium III
Rising Scientist Session

SIRT1 has been identified as playing a role in the maintenance of epithelial integrity and its alteration is often related tocarcinogenesis. However, the methylation and transcription status of SIRT1 in oral cancer has not been investigated. We
examined the methylation levels of SIRT1 in oral cancer tissues of betel quid (BQ) chewing and non-BQ chewing patients, andinvestigated whether the methylation level reflects the transcription level in an in vitro model. In addition, we examined SIRT1
methylation status in smear samples of macroscopically healthy buccal mucosa from individuals with a habit of BQ chewing.The
DNA methylation level of SIRT1 in the tissue samples was analyzed using methylation-specific PCR (qMSP). Gingival epithelial
cells were treated with arecoline, DNA methylation, mRNA, and protein expression levels of SIRT1 were analyzed by using
qMSP, quantitative RT-PCR, and western blotting, respectively. DNA methylation levels of SIRT1 were assessed by using qMSP
in the smear samples.DNA methylation of SIRT1 was significantly higher in tissue samples from BQ chewing patients with oral
cancer than in samples from non-chewing oral cancer patients or controls. Our in vitro model showed that hypermethylation
is followed by downregulation of the transcriptional level of SIRT1. The methylation level of SIRT1 in macroscopically healthy
oral epithelium of BQ chewing subjects is higher than that of non-chewing subjects. The duration of BQ chewing habits wascorrelated positively to the frequency of SIRT1 hypermethylation.Our results indicate that DNA hypermethylation of SIRT1 isinvolved in the occurrence of oral cancer and that hypermethylation in the oral mucosa of BQ chewers may be a predictive
marker for the occurrence of malignant transformation. This is the first report that showed DNA hypermethylation in clinically
healthy oral epithelium of BQ chewers. Our study shows evidence that DNA hypermethylation may be an early event of oral
carcinogenesis prior to observable clinical changes.

Symposium II

S. ISLAM, O. UEHARA, H. MATSUOKA, Y. ABIKO, I. CHIBA

Symposium I

Sirtuin1 DNA hypermethylation may be a biomarker for malignant transformation

Special Lecture052:

Greeting

Objective
Glucose metabolism is crucial for tumor growth and closely associated with the response to tumor treatment. Metformin, a
traditional anti-hyperglycemia drug, has been demonstrated to be beneficial for many malignancies. However, the relationshipbetween its anticancer effect and altered glucose metabolism remains elusive in oral cancer. In the present study, we aim toelucidate the effect of metformin on glucose metabolism of normal cell and oral squamous cell carcinoma cell lines.
Methods
Normal cell (HaCaT) and cancer cells (HSC-2 and HSC-3) were grown with metformin for 4 days and the cell number wasdetermined by cell counting. Cells, treated with or without metformin, were obtained at the logarithmic growth phase and thenthe real-time monitoring system was applied to detect acid production (lactic acid from the glycolysis and bicarbonic acid fromthe citric acid cycle) from glucose in a fixed pH environment (pH 7.5).
Results
The cell growth of HSC-2 treated with 1mM metformin was significantly inhibited by 33.1% and 32.2% at 72h and 96h,
respectively (p<0.01). However, metformin could not inhibit the cell growth of HaCaT and HSC-3. Consistent with the effect of
metformin on cell growth, 1mM metformin suppressed the rate of acid production from glucose by 44.6% in HSC-2 (p<0.05) but
not in HaCaT and HSC-3.
Conclusion
Our results suggest that metformin inhibits the cell growth of HSC-2 by suppressing the acid production from glucose. But
metformin shows heterogeneous effect on oral cancer cell lines, which is associated with the altered glucose metabolism.
Moreover, monitoring acid production might be used to evaluate the efficacy of metformin. The further study will be required
to elucidate the underlying mechanism caused by metformin on glucose metabolism in oral cancer.

Keynote Lecture051:

Poster Presentation

─ 99 ─

053:

Role of EGFR-mediated MOB1 phosphorylation on Hippo pathway regulation
T. ANDO
Center of oral clinical examination, Hiroshima Univeresity Hospital, Hiroshima, JapanThe Hippo pathway and its downstream targets, the YAP/TAZ coactivators, play a central role in cancer cell growth. The Hippo
pathway, composed of MST1/2, LATS1/2 kinases and their adaptor proteins SAV1 and MOB1, is dysregulated and YAP/TAZ are
aberrantly activated in oral squamous cell carcinoma (OSCC). However, the genetic alterations triggering YAP/TAZ activation in
OSCC remains to be unclear. In this regard, we focused on EGFR, which is amplified and overexpressed in OSCC and regarded
as a therapeutic target. But whether EGFR controls YAP activation is still poorly understood. Therefore, the aim is to clarify therole of EGFR on the regulation of Hippo pathway in OSCC. OSCC and lung adenocarcinoma cell lines, and HEK293A cells wereused. Western blot, immunoprecipitation, qPCR, immunofluorescence analysis, in vitro kinase assay, proliferation assay were
performed. We found that EGFR can directly phosphorylate the core Hippo pathway component MOB1 and inactivates LATS1/2,
upstream kinases of YAP/TAZ, thereby promoting the transcription of growth-related genes. Transcriptomic analysis revealed
that EGFR inhibitor inactivates YAP/TAZ and suppresses YAP/TAZ-regulated gene expression. Remarkably, loss of LATS1/2,
resulting in full activation of YAP/TAZ, was sufficient to confer resistance to erlotinib in OSCC and lung cancer cells with EGFR
alterations. Our findings elucidated that EGFR-MOB1-YAP/TAZ plays a pivotal role on cancer cell proliferation in OSCC. Emerging
evidence show that YAP/TAZ activation is important for EGFR targeting therapy resistance. Given the evidence and our results,
EGFR targeting therapy inactivates YAP/TAZ through MOB1 phosphorylation, then YAP/TAZ are likely to be re-activated byunknown mechanism. Therefore, inhibition of YAP/TAZ in combination with EGFR targeting therapy might be beneficial toprevent treatment resistance, and ultimately to halt cancer progression and recurrence. This project was supervised by J Silvio
Gutkind (Principal investigator, University of California, San Diego).

054:

Sema3A-AKT Axis In Salivary Gland And Adenoid Cystic Carcinoma Developments
T. FUJIMOTO1, S. FUJII2, T. KIYOSHIMA2
1

School of Dentistry, Kyushu University, 2Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Facultyof Dental Science, Kyushu University

Recently, we demonstrated that Wnt/β-catenin signaling negatively regulated cellular growth through reduced Semaphorin3A(Sema3A) expression in odontogenic epithelial cells and its involvement in tooth germ development (Sci Rep, 2019). Although
the developmental process in salivary gland may share the same mechanisms with tooth germ, the effect of Sema3A signalingon salivary gland development remains unclear. Here, we conducted to investigate the function of Sema3A signaling in salivary
gland development and adenoid cystic carcinoma (ACC) cell proliferation.We developed the salivary gland organ culture systemwith murine submandibular salivary gland (SMG) rudiments at embryonic day 13. In the organ culture system, normal tempospatial development of the SMG rudiment or salivary gland organ, which is similar to in vivo situations, was confirmed. The
treatment with CHIR99021, a GSK3β inhibitor, activated Wnt/β-catenin signaling but decreased Sema3A expression in the SMG
rudiment culture and ACC cell lines. Immunohistochemical analysis demonstrated that Sema3A was highly expressed in thesalivary gland epithelial cells. Loss-of-function experiments with a Sema3A inhibitor showed the decrease of total epithelialarea, the numbers of buds and proliferating cells, and AKT activation. Consistently, loss-of-function experiment reduced cellproliferation and AKT activation in the ACC cell lines.These results suggest that Wnt/β-catenin signaling reduces Sema3A
expression and the Sema3A-AKT axis promotes epithelial cell proliferation to regulate salivary gland development and ACC cellproliferation.

─ 100 ─

Effect of Ethinyl Estradiol on Mandibular Condyle of Female Rats
S. YAKLAI, R. PECHAYCO, Y. ABE, A. TAKIZAWA, I. MIZOGUCHI, T. TAKAHASHI, M. CHIBA
Graduate School of Dentistry, Tohoku University

Greeting
Special Lecture

Objectives: Idiopathic condylar resorption (ICR) of the mandibular condyle is commonly observed in perimenopausal women.
Recent clinical studies have reported a correlation between oral contraceptives (OC) and ICR. This study aimed to establish
a young female rat model and examine the effect of ethinyl estradiol (EE), a main component of OC and an active analog of
estrogen, on the mandibular condyle.Methods: Seven-week-old female Sprague-Dawley rats with normal estrus cycle wereorally treated with peanut oil (PO; vehicle, n = 6) or EE (0.4, 1, 5, 10, and 50 μg/kg/day, n = 6) for 8 weeks. After confirming
the estrus stage, blood was collected from the animals for serum 17β-estradiol measurements. The right mandibular condyles
and knee joints were subjected to micro-computed tomography, histological staining, and histomorphometric analysis. Total
RNA was extracted from the left mandibular condyles and real-time polymerase chain reaction was performed.Results: The
bodyweight of the rats gradually increased in all groups. Serum 17β-estradiol levels were significantly decreased in the EE10
and EE50 groups (p < 0.05). The EE-treated rats (50 μg/kg/day) demonstrated an increase in bone mineral density (BMD)
and a decrease in the hypertrophic layer thickness of the mandibular condylar cartilage (MCC) compared to the PO-treatedrats (p < 0.05). The BMD, bone volume fraction and trabecular bone number were increased in the EE-treated tibia bone.
Moreover, the thickness of the growth plate in the tibia and articular cartilage in the femoral bone decreased significantly (p< 0.05).Conclusions: EE administration may suppress the estradiol cycle and inhibit long bone growth, which is similar to the
estrogen effect. Moreover, EE may terminate the growth and development of the mandibular condyle prematurely, which may
compromise the properties of MCC and lead to ICR.

Keynote Lecture055:

Symposium I

Histone methyltransferase SETDB1 negatively regulates PTH/PTHrP receptor in chondrocytes
P. THIHA, N. HIGASHIHORI, S. KANO, K. MORIYAMA
Department of Maxillofacial Orthognathics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University

Rising Scientist Session
Poster Presentation

─ 101 ─Symposium III

Objectives: SETDB1 is a histone methyltransferase which represses gene expression by catalyzing lysine 9 of histone H3
trimethylation. We previously showed that conditionally inactivation of Setdb1 only in neural crest-derived cells by crossing
Wnt1-Cre deleter strain to the floxed allele of Setdb1 (Setdb1 CKO) resulted in Meckel´s cartilage enlargement instead of thedegeneration that normally occurs in the later stages of mandibular development. Here¸ we show that the proliferation ofchondrocytes is regulated by SETDB1 along with the downregulation of PTH/PTHrP receptor.
Methods: Setdb1 was knocked down or overexpressed in a mouse chondrogenic cell line¸ ATDC5¸ by transfecting the cells withshort interfering RNA against Setdb1 or wild-type Setdb1 expression vector¸ respectively. The proliferation of cells was detectedby BrdU incorporation. RNA was extracted¸ and gene expressions were examined by quantitative RT-PCR. Immunofluorescencestaining of paraffin sections of embryonic days 13.5¸ 14.5¸ and 15.5 mice or transfected ATDC5 cells was performed to detect
PTH/PTHrP receptor.
Results: Setdb1 inhibition in ATDC5 cells showed increased proliferation¸ and the expression of Pthrp and Pth1r was also
increased in these cells. Converse results were observed when the wild-type Setdb1 was overexpressed. Strong staining of PTH/
PTHrP receptor was observed in Meckel´s cartilage in Setdb1 CKO mice on embryonic days 13.5¸ 14.5¸ and 15.5¸ compared tothat in their control counterparts in which the staining was barely detected. Similarly¸ Setdb1 inhibition in ATDC5 cells clearlyenhanced the staining of PTH/PTHrP receptor in the cytoplasm and membrane. However¸ PTH/PTHrP receptor was only
observed around the nucleus when Setdb1 was overexpressed.
Conclusions: Increased proliferation of chondrocytes are caused in part by the upregulation of PTH/PTHrP receptor as a resultof Setdb1 inhibition¸ which may lead to abnormal enlargement of Meckel´s cartilage¸ and its prolonged presence in Setdb1 CKO
mice.

Symposium II

056:

057:

Generating MSC Spheroids Recovers Stemness Characteristics for Cortical Bone Formation
Y. OHORI, K. NIIBE, H. EGUSADivision of Molecular and Regenerative Prosthodontics, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan

Objectives: Alveolar bone resorption limits the effectiveness of dental treatments. Therefore, regenerative approaches havegarnered attention. Mesenchymal stem cells (MSCs) represent promising candidates for regenerative therapy. In vitro expansionof MSCs is often required prior to in vivo transplantation. Gradual loss of stemness via repeated passage may significantly limit
the therapeutic potential of MSCs. We previously successfully established a novel three–dimensional (3D) culture method
to generate MSC spheroids that maintain multipotency in vitro. Objectives of the present study were to optimize 3D culture
methods and to investigate regenerative ability of MSC spheroids in vivo.
Methods: Human bone marrow–derived MSCs were cultured under adherent conditions for an extended period (16–18
passages) to produce long–term adherent MSCs (lMSC–ad). After expansion, lMSC–ad were harvested and 3D cultured undershaking conditions in neural stem cell medium for 21 days to produce MSC spheroids (lMSC–sph). Cell characteristics were
investigated using a differentiation assay, RT–PCR, and histochemistry. For the in vivo experiment, cells were implanted into
critical sized–femur bone defects of SD–rats. After 3 weeks, femur bones were excised and quantitative assessment of 3D bonemorphometric parameters was performed using micro X–ray computed tomography.
Results: Relative to lMSC–ad, lMSC–sph demonstrated marked multipotency recovery, as suggested by high expression ofstem cell and anti–inflammatory markers. This phenotypic change may reflect recovery of stem cell functionality. Indeed, acontiguous mineralized structure was observed in cortical regions of lMSC–sph–implanted samples, and average bone mineraldensity was significantly higher in lMSC–sph–implanted samples (ANOVA; p < 0.05). These data suggest that lMSC–sph aresuperior to lMSC–ad in promoting bone regeneration.
Conclusions: Even after long–term proliferation, MSC spheroids 3D cultured under novel shaking conditions recovered at least
some stem cell characteristics and enhanced bone regeneration in vivo. This may facilitate alveolar bone regeneration as a formof regenerative dentistry.

058:

The bHLH transcription factor HAND1 is involved in cortical bone volume through the regulation ofcollagen expression
N. FUNATO1, Y. TAGA3, L. E. LAURIE1, C. TOMETSUKA3, M. KUSUBATA3, K. OGAWA-GOTO3
1

Department of Signal Gene Regulation, Tokyo Medical and Dental University, Tokyo, Japan, 2Research Core, Tokyo Medical and Dental
University, Tokyo, Japan, 3Nippi Research Institute of Biomatrix, Ibaraki, Japan

Objective: Temporally and/or spatially altered expression of the members of the collagen family of genes results in numerous
bone defects in humans and mice. However, the mechanisms of collagen expression associated with bone size control remain
largely unknown. The basic helix-loop-helix (bHLH) transcription factor, HAND1, is expressed in the developing long bones andis involved in their morphogenesis. To understand the functional role of HAND1 in the postnatal development of long bones,
we overexpressed Hand1 in osteochondroprogenitors and found that the bone volumes of the cortical bones were decreasedin Hand1-overexpressing mice compared to those in wild-type mice. Methods: Using Hand1-overexpressing mice conditionallydriven by Twist2-Cre (Hand1Tg/+; Twist2-Cre), bone staining, histology, and immunohistochemistry, micro-computed tomography,
real-time quantitative PCR, and liquid chromatography/mass spectrometry (LC/MS) analysis were performed. Results: The
continuous expression of Hand1 downregulated the expression of types I, V, and XI collagen genes in the diaphyses of thelong bones, and was associated with decreased expression of Runx2 and Sp7/Osterix, which encode transcription factors fortransactivation of fibril-forming collagen genes. Moreover, members of the microRNA-196 family, which specifically target
the 3 prime untranslated regions of Col1a1 and Col1a2, were significantly upregulated in Hand1-overexpressing mice. Mass
spectrometric analysis revealed that the expression ratio of type V and XI collagens increased during postnatal developmentin the diaphysis of wild-type mice, whereas their increase was delayed in Hand1-overexpressing mice. Conclusion: Our
results demonstrate that HAND1 regulates bone size and morphology through osteochondroprogenitors, at least partially bysuppressing the postnatal expression of collagen fibrils in the cortical bones.

─ 102 ─

Oxygen tension-dependent expression of monocarboxylate transpoter-1 is a prerequisite event foroxidative death of chondrogenic ATDC5 cells induced by interleukin-1β.
M. TANAKA1, Y. MIYAMOTO1, K. YOSHIMURA1, K. SASA1, K. IKEZAKI1,2, T. SHIROTA2, R. KAMIJO1
1

Department of Biochemistry, Showa University School of Dentistry, Tokyo, Japan, 2Department of Oral and Maxillofacial Surgery,Showa University School of Dentistry, Tokyo, Japan

Greeting
Special Lecture

Objectives: Articular cartilage is a typical avascular tissue. Its superficial and deeper parts' oxygen tension is estimated to
be 6% and 1%. Its destruction begins from the surface in joint disorders including osteoarthritis. We previously reported
that monocarboxylate transporter (MCT)-1, a transmembrane transporter for monocarboxylates such as lactate, played anessential role in interleukin-1β(IL-1β)-induced expression of NADPH oxidase (NOX)-2, a reactive oxygen species (ROS)-producing
enzyme, and ROS-dependent death of mouse chondrogenic ATDC5 cells cultured in a normal condition (20% oxygen). Here,
we investigated the effect of oxygen tension on IL-1β-induced events, including cell death in ATDC5 cells. Methods: ATDC5
cells were treated with IL-1β (1 ng/mL) for various periods under 1-20% oxygen. We assessed cell survivability by measuring
the optical density after toluidine blue staining of the cells. We also examined the expression of mRNAs quantitatively by realtime RT-PCR. Results: IL-1β induced the death of ATDC5 cells under 20% and 6% oxygen but did not under 2% and 1% oxygen.
A NOX inhibitor, apocynin, suppressed cell death. IL-1β induced the expression of Mct1 and Nox2 mRNAs under 20% oxygenin 6 and 24 hours, respectively, but not under 2% oxygen. On the other hand, a 3-hour incubation with IL-1β upregulated theexpression of Nox2 (inducible nitric oxide synthase) mRNA irrespective of oxygen tension. Mct1 siRNA suppressed the IL-1βinduced expression of Nox2. Inhibition of hypoxia-inducible factor (HIF)-1α did not augment the IL-1β-induced expressionof Mct1 or Nox2 under 2% oxygen. Conclusion: The results indicate that IL-1β induces the expression of MCT-1 in an oxygen
tension-dependent manner without regulation by HIF-1α, which precedes NOX-2 expression, ROS production, and cell death inchondrogenic ATDC5 cells. The notions obtained in our study suggest that regulation of MCT-1 in articular cartilage would be a
promising approach to treat joint diseases including jaw arthritis.

Keynote Lecture059:

Symposium I

Effects of Anticancer Drugs on Mouse Tooth Germ Development
Y. TSUNODA1, S. NAKA1, R. OKAWA2, K. NAKANO2, M. MATSUMOTO-NAKANO1
1

Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Japan,
Department of Pediatric Dentistry, Division of Oral Infection and Disease Control, Osaka University Graduate School of Dentistry, Suita,
Osaka, Japan

2

Rising Scientist Session
Poster Presentation

─ 103 ─Symposium III

Objectives: Chemotherapy at an early age for childhood malignancy causes severe disturbances in odontogenesis such as dental
agenesis and microdontia, and also inhibits tooth root development. It has been suggested that these conditions are causedby administration of an alkylating agent for anticancer therapy during the time of formation of permanent teeth. The purposeof this study was to investigate the effects of cyclophosphamide (CPA), an alkylating agent, on development of tooth germs
in mice.Methods: Mandibular first molar tooth germs were collected from 16-day-old mouse embryos and cultured using the
Trowell method. CPA (0.21 mg/mL) was added on the first day of culture in the experimental group, while nothing was added
to the control culture. Histopathological examinations and molecular biological analyses of tooth germs cultured for 7, 14, or
21 days were performed.Results: HE staining revealed a disorganized array of ameloblasts and odontoblasts in the experimentalgroup after 21 days. Also, qRT-PCR results showed increased CK14 expression and decreased vimentin expression at 21 days in
the experimental group as compared to the control. In addition, type I collagen expression was decreased after both 14 and 21days, while fibronectin expression was significantly reduced after 21 days (P<0.001) in the experimental group. Furthermore,large numbers of TUNEL-positive cells were found in the epithelial area and tooth papillae after 14 days in the experimentalgroup, with the number increased in the epithelial area after 21 days, whereas those were decreased in dental papillae ascompared to 14 days.Conclusions: CPA may inhibit DNA synthesis in mitotic inner enamel epithelial and dental papilla cells, thus
causing inhibition of normal growth and differentiation in the tooth germ. In addition, CPA was found to induce histologicalchanges in ameloblasts and odontoblasts, resulting in an abnormal tooth morphology.

Symposium II

060:

061:

Trehalose, a natural sweetening compound, suppresses osteoclast differentiation.
S. NEGISHI, K. YOSHIMURA, R. KAMIJO
Department of Biochemistry, Showa University School of Dentistry

Objectives: Control of osteoclast formation in periodontal disease is an essential issue for patients' QOL. We are interested
in the effects of food components on osteoclast differentiation because it would be possible to develop such compounds
as agents to control alveolar bone resorption in periodontitis. We reported at JADR 2018 that sucrose inhibited osteoclastdifferentiation. However, sucrose is one of the causative sugars of dental caries. In the present study, we expanded our research
to find dietary sugars that effectively inhibit osteoclast differentiation.Methods: Bone marrow cells obtained from male ddY
mice were cultured with M-CSF to propagate macrophages, which were further cultured for 3 days with M-CSF and RANKL to
induce their differentiation into osteoclasts in the presence of various sugars. We performed tartrate-resistant acid phosphataseactivity staining to detect and count osteoclasts. We assessed the expression of the genes related to osteoclast differentiation
by real-time RT-PCR. We also evaluated the effects of sugars on the viability of macrophages by the reduction of MTS reagent.
Results: Among the sugars tested, trehalose, a naturally-occurring disaccharide consisting of two α-D-glucose units with α1,α1 glycosidic bond, suppressed osteoclast differentiation induced by RANKL. Trehalose at 5 mmol/L or higher suppressed
osteoclast differentiation in a concentration-dependent manner. While 25 mmol/L trehalose completely suppressed osteoclastdifferentiation, sucrose at the same concentration only partially suppressed it. Mannitol, a sugar alcohol used for osmotic
diuretic, at 50 mmol/L did not affect osteoclast differentiation, indicating that change in osmolarity did not explain the effect oftrehalose. Trehalose significantly suppressed the expression of Nfatc1, the master gene of osteoclast differentiation. Besides,
trehalose did not affect the viability of macrophages.Conclusion: Trehalose inhibited osteoclast differentiation by suppressing
the expression of Nfatc1. Its high safety to the human seems preferable for developing an anti-bone resorptive agent applicableto periodontitis patients.

062:

Computational chemistry of phospholipid mineralization
E. HARA1, N. KUNIOSHI2, M. OKADA1, T. MATSUMOTO1
1

Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2Departmentof Materials Science, Graduate School of Fundamental Science and Engineering, Waseda University, Tokyo, Japan

Previously, we have found that cell membrane nanofragments (phospholipids) were the nucleation site for bone formation(Hara ES et al., ACS Biomater Sci Eng, 2018). In addition, we showed that cell membrane nanofragments could promote bonelike mineral (calcium phosphate) formation in only 1 day (Hara ES et al., J Mater Chem B, 2018). However, the mineralization
mechanisms of phospholipids are still unclear. This study aimed to evaluate the ability of different phospholipids to mineralize
in vitro, and to analyze the energy required for phospholipid cleavage and calcium phosphate formation using in silico quantum
chemistry-based tools. Chloroform-dissolved phospholipids were applied onto a glass-bottom dish, and after complete dry,a 2 mM CaCl2 solution was poured into the dish, which was incubated in at 37C, 5% CO2 and 98% humidity for 2 days. The
phospholipid/mineral complexes were then collected in small tubes and centrifugally-washed 3 times with ultra-pure water(Milli-Q) and dissolved in 0.1% HCl for quantitative analysis of calcium levels using a simultaneous multi-element analysis
atomic absorption spectrophotometer (AAS). A detailed analysis of the cleavage reaction kinetics focusing on the steric factorof each phospholipid molecule was performed to evaluate the affinity of each molecule for binding to calcium ions. The
Gaussian16 molecular orbital program was used at the B3LYP/6-31(d, p) level of theory. The results showed that among several
phospholipids, phospholipid X showed the highest mineralization ability in vitro, as determined by AAS. Quantum chemical
calculations revealed that the mineralization reaction of phospholipid X probably proceeded in the following order: (1) bindingof Ca ions (2) removal of the hydrophilic head, (3) removal of the hydrophobic tail, and formation of calcium phosphates. These
results reveal important steps of phospholipid mineralization. Future studies are required to clarify the exact mechanisms ofphospholipid mineralization.

─ 104 ─Histological study of dentin bridge formed beneath MTA after pulpotomies in rat molars
A. TANAKA, T. TANASE, K. KOJIMA, H. HOMMA, A. SAKURAI, S. SHINTANI
Department of Pediatric Dentistry, Tokyo Dental College, Tokyo, Japan

Greeting
Special Lecture

It is known that odontoblasts are differentiated from the undifferentiated mesenchymal cells by stimulation. Recently, a lot of
studies on pulpotomy indicate that the clinical results are better using mineral trioxide aggregate (MTA) than CH. Kimura et al.
(2016) suggested that transient receptor potential ankyrin (TRPA) channel is involved in dentin formation. However, it is known
whether MTA and CH activate TAPA1 channel in vivo. The aim of this study is to clarify the histological differentiation about DB
and the association TRPA1 channel using MTA and CH on pulpotomy. Therefore, we made rat models of the pulpotomy at first.
The maxilla first molars from postnatal week 7 Wistar rats were performed pulpotomy using MTA with rubber dam isolationand microscope. We fixed the rats after the progress for 4 weeks from surgical operation day. The maxilla including the firstmolar was embedded in paraffin by a conventional method. The serial sagittal sections of maxilla first molars were made forhematoxyline-eosin staining.The DB was observed in the region facing MTA, and the pulp did not through to outside due to the
DB. It was found that the DB included lacuna and dentinal tubules. The dentinal tubules were irregular and abnormal number.
Odontoblast-like cells were detected bottom of the DB. There is no inflammation response in the pulp and apical area.Many
studies were investigated about MTA in vitro. Although there were studies about direct capping using MTA in vivo, no study
about pulpotomy using MTA in vivo. There is one of the causes, it is difficult to perform pulpotomy in the size of rat molar.
However, we succeeded in the pulpotomy in this study.We can perform pulpotomy on rat tooth with rubber dam isolation andmicroscope.

Keynote Lecture063:

Symposium I

The effect of micro-sized titanium on osteoblast differentiation
N. OMORI, H. NAKATA, S. KURODA
Department of Oral Implantology and Regenerative Dental Medicine, Division of Oral Health Sciences, Graduate School of Medical and
Dental Sciences, Tokyo Medical and Dental University

Rising Scientist Session
Poster Presentation

─ 105 ─Symposium III

Objectives
The purpose of this study is to investigate the effects of micro-sized titanium on osteoblasts and to reveal the mechanism bywhich the titanium acquires its osseointegration.
Methods
MC3T3-E1 preosteoblastic cell culture was started in 6-well plates with 1 × 10 5 cells/well and cultured in a growth medium(αMEM, 7 mL), exposed to different amounts of micro-sized titanium particles (0.1 g, 0.5 g and 1.0 g) [Titanium, Powder, 45
μm, 99.9%, FUJIFILM] dialyzed through cellulose tubes [pore size: 5nm, Kenis] in the medium for 24 hours. And then the culture
medium was replaced with the same amount of the fresh growth medium as group "GM" or an osteogenic medium as group"OG". Subsequently, ALP staining was performed at 3 and 7 days of culture after changing medium with growth or induction
medium. The staining was observed using BZ-X700 [KEYENCE] and the stained area was calculated with Image J software. The
post hoc test with one-way ANOVA was statistically processed using the Tukey test with p-value of 0.05.
Results
There was no significant difference in ALP staining by the titanium exposure in all titanium particle amounts in GM whereas
the stained area was statistically larger by 0.1 g and 0.5 g of the particles than by 1.0 g and 0 g (negative control) in OG at day
3. Afterward, the stained area was significantly smaller by 1.0 g than by 0.1 g, 0.5 g and 0 g in GM; however, in OG, the stained
area enlarged by 0.1g and 0.5 g of the titanium particles than by 1.0 g and 0 g at day 7.
Conclusions
Osteogenic differentiation of MC3T3-E1 cells was promoted by 0.1 g and 0.5 g of micro-sized titanium particle amounts; on theother hand, 1.0 g had no effect on osteoblast differentiation.

Symposium II

064:

065:

Comparison in physical properties of synthetic carbonate apatite and allogeneic bone graft substitute
N. KIMURA, S. KATO, E. ARIMA, N. KITAMURA, K. YAMANAKA, F. FUSEJIMAGC Corporation, Tokyo, Japan

Objectives: Autogenous bone have been the gold standard for bone augmentation, but invasion to the healthy site remain
as a concern. There has been a demand for bone graft substitutes which has potential to be replaced with autogenous bone.
We have developed a novel bone graft substitutes "Cytrans Granules (Cyt)" consisting synthetic carbonate apatite, which is
the main component of human bone. It is reported that Cyt shows osteoconductivity at similar or higher level of allogeneic
bone graft substitutes, but the mechanism behind have not been clarified. In this study, we have compared the composition,
crystal structure and resorption property of Cyt to synthetic Hydroxyapatite (HAp) and freeze-dried bone allograft (FDBA) as
an allogeneic bone.Methods: Cyt was used as test sample, FDBA and three types of HAp (HAp-1, HAp-2, HAp-3) were used ascontrol. Composition and crystal structure were evaluated by using Fourier transform infrared spectroscopy (FT-IR) and powder
X-ray diffraction (XRD). Crushing strength was measured by universal testing machine. Resorption property was measured as
amount of calcium ion dissolved from the samples in neutral solution (pH7.3) and weak acidic solution (pH5.5).Results: XRD
pattern showed that all samples have apatitic crystal structure. FT-IR spectrum showed that Cyt and FDBA contains carbonate
group. Synthetic Hydroxyapatite had higher crushing strength, followed by FDBA and Cyt. Among all samples, dissolution
at neutral solution was at low level. In weak acidic solution, Cyt and FDBA showed higher rate of dissolution compared tosynthetic Hydroxyapatite.Conclusions: It was confirmed that Cyt and FDBA are Hydroxyapatite containing carbonate group.
Cyt had composition, crystal structure and mechanical properties similar to those of FDBA. From the result of dissolution test,
Cyt and FDBA were stable in neutral body fluid, and were dissolved in weak acidic solution resembling the pH produced byosteoclast. These results indicate that these two materials could be resorbed by osteoclasts. It is suggested that Cyt has similar
characteristics to allogeneic bone, which may be the reason for Cyt to exhibited osteoconductivity at similar or higher levelcompared to allogeneic bone.

066:

Novel bio-active adhesive monomer CMET stimulates human dental pulp stem cells differentiation
toward odontoblast phenotype: a comparative study
Y.J. QIU, T. SAITODivision of Clinical Cariology and Endodontology, Department of Oral Rehabilitation, Health Sciences University of Hokkaido, Hokkaido,
Japan

Objectives: The present study aims to evaluate the in vitro effect of the novel adhesive monomer CMET, a calcium salt of
4-methacryloxyethyl trimellitate (4-MET), on the proliferation, mineralization and differentiation of human dental pulp stem
cells (hDPSCs), comparing with 4-MET, calcium hydroxide (CH), and mineral trioxide aggregate (MTA).Methods: hDPSCs were
cultured in Dulbecco's modified Eagle's medium (DMEM) supplemented with 10% fetal bovine serum, 50 units/mL penicillin,
and 50 μg/mL streptomycin. Mineralization reagents including 10 mM β-glycerophosphate and 50 μg/mL ascorbic acid
were incorporated upon confluence. The powder of four tested materials (CMET, 4-MET, CH and MTA) was first dissolved
in distilled water (dH2O) and then was diluted by DMEM to yield final concentrations. Solvent (dH2O) was used as a control.
Cell viability was assessed using CCK-8 assay. Realtime RT-PCR was used to quantify the mRNA expression of odontogenic
markers. Mineralization inducing capacity was evaluated by alkaline phosphatase (ALPase) activity and alizarin red S staining.
Statistical analyses were performed using one-way ANOVA and post hoc Tukey's HSD test, with the significance level at
1%.Results: Cell viability was significantly greater in the CMET- and MTA-treated (10%, v/v) groups than that in other groups,
higher concentrations of each material exhibited cytotoxicity to different extents (P < 0.01). CMET showed the lowest toxic
effect on hDPSCs. CMET treatment augmented the mRNA expression levels of odontogenic markers (P < 0.01), while no great
up-regulation was observed in other three material treated groups. The addition of CMET significantly increased the ALPase
activity of hDPSCs on day 14 and 21, then decreased on day 28 (P < 0.01). The calcific deposition of hDPSCs was accelerated
by the addition of CMET, CH, and MTA on day 30 and 32 (P < 0.01), but it was inhibited by 4-MET on both days.Conclusions:
The present results indicated that the differentiation of hDPSCs was stimulated into odontoblast phenotype by the addition of
CMET, while the addition of CH and MTA rather promoted hDPSCs calcific deposition than differentiation into odontoblast. The
results provided evidence that CMET is a promising bio-active material in dentin regeneration.

─ 106 ─Hydrogel-based biomechanical environment for understanding Meckel's cartilage fate
M. FARAHAT1, G. A. S. KAZI2, E.S. HARA1, T. MATSUMOTO1
1
Department of Biomaterials, Okayama University, Okayama, Japan, 2Department of Applied Life Systems Engineering, Graduate Schoolof Science and Engineering, Yamagata University

Greeting
Special Lecture

Objectives:The purpose of this study was to,1.systematically investigate the course of Meckel's cartilage during embryonicdevelopment from a biomechanical perspective.2.In vitro mimicking the biomechancial miliu affecting the cartialge
development via mechcanically-tuned hydrogel culture systemMethods: 1. Histomophological and biomechanical (stiffness)changes in the Meckel's cartilage were analyzed from embryonic day 12 (E12) to post-natal day 0 (P0).2. E 14 and E15 cartilage
rods were isolated and cultured in mechanically-tuned 3D hydrogel culture system (10, 20 and 40 kPa hydrogel). After, 5-7 daysin culture, immunofluorescence analysis of metalloproteinase (MMP-1 and MMP-13) was carried out.3. Micro-CT images of thecollected samples were obtained to detect the mineralized tissue formation.4. Time-lapse imaging of the development of the
cartialge was done to detect chondrocyte cell burstResults: Our results revealed remarkable changes in the morphology and sizeof chondrocytes, as well as the occurrence of chondrocyte burst, which is an often seen phenomenon preceding endochondral
ossification, in the vicinity of the mineralization site. The mechanically-tuned 3D hydrogel culture system results showed that,at the anterior region, a moderately soft environment (10 kPa hydrogel) promoted chondrocyte burst and ossification. On thecontrary, at the middle region, a more rigid environment (40 kPa hydrogel) enhanced cartilage degradation by inducing a higher
expression of MMP-1 and MMP-13.Conclusions: These results indicate that differences in the biomechanical properties of thesurrounding environment are essential factors that distinctly guide the mineralization and degradation of Meckel's cartilage,
and would be valuable tools for modulating in vitro cartilage and bone tissue engineering.

Keynote Lecture067:

Symposium I

Evaluation of Interleukin – 8 In Human Dental Pulp
S. TALWAR1, R.R. NAWAL1, A. KAUSHIK1, R. KONER2
1

CONSERVATIVE DENTISTRY AND ENDODONTICS, MAULANA AZAD INSTITUTE OF DENTAL SCIENCES, New Delhi, DELHI, INDIA,
BIOCHEMISTRY, MAULANA AZAD MEDICAL COLLEGE, NEW DELHI, DELHI, INDIA

2

Symposium III
Rising Scientist Session

Objectives: To evaluate and compare the IL – 8 levels in the normal, reversibly inflamed and irreversibly inflamed dental
pulpMethods: The study population was composed of 35 patients who underwent dental treatment at the Department ofConservative Dentistry and Endodontics, Maulana Azad Institute of Dental Sciences, New Delhi. Cases subject to testingGroup 1 : Intact vital teeth indicated for orthodontic extractions Group 2 : Teeth with reversible pulpitis Group 3 : Teeth withsymptomatic irreversible pulpitis Sampling, Transport and Storage of Blood Samples Following access preparation, blood
sample was obtained with a micropipette and transferred immediately into numbered reaction tubes (e-cups). Serum wasremoved, diluted with the appropriate diluents, and assayed immediately. IL - 8 levels were assessed using ELISA according
to manufacturer’s recommendations.Results: The IL – 8 levels obtained were in picogram/ml and were subdivided as follows:
Low level < 100 pg/ml Mid level - 100 – 500 pg/ml High level > 500 pg/ml Out of 35 samples, 04 were normal pulp, 05 werereversible pulpitis and 26 were irreversible pulpitis cases (diagnosed clinically). Results have been provided in the table that is
attached with submissionConclusions: Strong correlation was seen between values of IL – 8 and level of pulpal inflammation. In
fact, very high value of IL -8 (more than 2000 pg/ml) were seen only in irreversible pulpitis cases and not in reversible pulpitis
or normal cases. In few cases of clinically diagnosed irreversible pulpitis, low levels of IL-8 signifies that other inflammatory
mediators may also play an important role in pulpal inflammation.

Symposium II

068:

Poster Presentation

─ 107 ─

069:

Interaction analysis of protein S100A7 in dental pulp tissue
M. WATANABE, M. OKAMOTO, H. HAILING, S. MATSUMOTO, K. MORIYAMA, Y. TAKAHASHI, M. HAYASHI
dentistry, Osaka University, Suita, Japan

Objectives: Organic dentin matrix components (DMCs) contain various kinds of bioactive molecules, which can be released byenzymatic digestion of DMCs during caries progression. We previously showed specific molecules from digested DMCs induced
by MMP-20 promoted wound healing process of pulp tissue. In the digested DMCs, we found protein S100A7 found was one of
the most effective molecules which could induce tertiary dentin formation, but the target molecules in the pulp tissue against
this protein was still unclear. In this study, interaction analysis was performed to detect the target molecules of S100A7 using
proteomic methods and to investigate the mechanism of the wound healing of dental pulp.Methods: Pull down assay was
performed to search for the interacted molecules with S100A7 in dental pulp tissue using rat primary pulp cells from rat incisors
and recombinant human S100A7 (PROSPEC, Israel) and, the results were visualized by SDS-PAGE. Then, liquid chromatographytandem mass spectrometry (LC-MS/MS) was performed to detect specific molecules comprehensively and quantitatively. To
identify the target molecules, proteome analysis software, Scaffold Viewer (Proteome Software, USA), was used to narrow
down the candidate target proteins. Then, the focused proteins were analyzed in terms of the function using Gene Ontology
categorization.Results: Pull down assay showed several specific proteins were interacted with S100A7. LC-MS/MS revealed 26
molecules might be interacted with S100A7 and showed that the molecules binding to S100A7 could be related to the functionof cellular process and biological regulation in Gene Ontology categorization.Conclusions: Some specific candidate molecules
were found that might interact with S100A7 in the pulp tissue could facilitate tertiary dentinogenesis.

070:

Lyve-1+ Pulpal Macrophages: M2-polarization and Response to Cavity Preparation
K. THOAI, K. TAZAWA, K. NARA, M. FUJII, K. HASHIMOTO, S. NODA, N. KAWASHIMA, T. OKIJI
Department of Pulp Biology and Endodontics, Tokyo Medical and Dental University, Tokyo, Japan

Lymphatic vessel endothelial hyaluronan receptor-1 (Lyve-1) is a CD44 homolog expressed on lymphatic endothelial cells
and certain macrophage subpopulations. We have reported that normal rat dental pulp contains Lyve-1+ macrophages coexpressing CD163, a marker of M2 macrophages. The purposes of this study were to examine the phenotype and biologicalactivity of Lyve-1+ macrophages in vitro and responses of Lyve-1+ macrophages to cavity preparation in rat molars.RAW264.7
cells, a murine macrophage cell line, were M2-polarized by MID cocktail (M-CSF, IL-4 and dexamethasone). Lyve-1 was forcibly
expressed by transfection of Lyve-1 expression vector into RAW264.7 cells. Lyve-1 mRNA and protein levels were determinedby RT-qPCR and western blotting, respectively. The mRNA levels of Arginase1 (Arg1), CD206, Interleukin-1a (IL-1a), IL-1b, IL-10,
Metalloproteinase 9 (MMP-9), and vascular endothelial growth factor (VEGF) were measured by RT-qPCR. Lipopolysaccharide(LPS, 100 ng/ml) was used to stimulate RAW264.7 cells. Dentinal cavities were prepared in upper first molars of Sprague Dawley
rats and Lyve1, CD68, CD163, and MCH class II was immunolocalized in the pulp with double-immunofluorescence staining.
Typical M2 markers (Arg1 and CD206) and Lyve-1 were highly induced in M2-polarized RAW264.7 cells. LPS-stimulation up- anddown-regulated pro-inflammatory (IL-1a and IL-1b) and anti-inflammatory (IL-10) cytokines, respectively. Enforced expression of
Lyve-1 induced up-regulation of angiogenic factors (MMP-9 and VEGF). Following cavity preparation, Lyve-1+ cells disappearedin the pulp tissue beneath the cavity at 1 day, whereas these cells gradually reappeared and distributed throughout the coronal
pulp at 7 days, when odontoblasts showed rearrangement beneath the cavity. Almost all Lyve-1+ cells co-expressed CD68 andCD163, but not MHC class II. Lyve-1 expression on macrophages was associated with M2-plarization and pro-angiogenic factor
expression in vitro. The delayed increase of Lyve-1+/CD163+ cells after cavity preparation suggests some association of thesecells with reparative responses of the pulp.

─ 108 ─DNA methylation of GJA1, BMP2 and BMP4 in a human cementoblast cell line induced bylipopolysaccharide.
T. MURAMATSU1, F. KOBAYASHI2, O. UEHARA3, C. ITO4, M. FURUSAWA2, Y. ABIKO5
1

Department of Operative Dentistry, Cariology and Pulp Biology, Tokyo Dental College, Tokyo, Japan, 2Department of Endodontics,
Tokyo Dental College, Tokyo, Japan, 3Department of Oral Growth and Development, Health Sciences University of Hokkaido, Tobetsu,
Japan., 4Oral Health Science Center, Tokyo Dental College, Tokyo, Japan., 5Department of Human Biology and Pathophysiology, Schoolof Dentistry, Health Sciences University of Hokkaido, Tobetsu, Japan.

Greeting
Special Lecture

The objective of this study is to examine DNA methylation of GJA1, BMP2 and BMP4 in human cementoblasts (HCEM) inducedby lipopolysaccharide (LPS).HCEM were cultured in osteoinduction medium. After 24 h, Escherichia coli LPS (1 μg/mL) was
added to the medium, which was changed every 2-3 days. Untreated samples were used as controls. Messenger RNA wasextracted after 4 weeks, and quantitative real-time polymerase chain reaction (qRT-PCR) forGJA1, BMP2, BMP4 and DNMT1 was
performed. Genomic DNA was extracted after 4 weeks, and quantitative methylation-specific polymerase chain reaction was
carried out for GJA1, BMP2 and BMP4. To detect mineralization, alizarin red and alkaline phosphatase staining were performed.
The cells were also treated with the DNA methyltransferase inhibitor 5-Aza-2'-deoxycytidine (5Aza) and examined. Decreased
expression of mRNA was seen in GJA1, BMP2 and BMP4 after 4 weeks (p<0.05). DNA hypermethylation was detected in GJA1,
BMP2 and BMP4 (p<0.05). Alizarin red staining and alkaline phosphatase staining revealed decreased mineralization levels in
HCEM stimulated with LPS. 5Aza abolished the effects of DNA methylation in HCEM stimulated with LPS. These results suggestthat long-term LPS stimulation induces DNA methylation of GJA1, BMP2 and BMP4 in HCEM.

Keynote Lecture071:

Symposium I

Effects of Non-thermal atmospheric pressure plasma on human deciduous dental pulp fibroblast-like cells
M. OKUNO1, K. HARADA2, S. AOKI1, S. KAWAI2, K. ARITA2
1

Department of Pediatric Dentistry, Graduate School of Dentistry, Osaka Dental University, Osaka, Japan, 2Department of Pediatric
Dentistry, School of Dentistry, Osaka Dental University, Osaka, Japan

Symposium III
Rising Scientist Session

Objective:Stem cells have been a recent focus of regenerative medicine research. They originate from various tissues including
human deciduous dental pulp. However, only a very small number of stem cells are present in dental pulp tissue and a large
number of cells are needed for clinical application.Non-thermal atmospheric pressure plasma (NTAPP) is a partially ionized gas
containing electrically charged particles and radicals at atmospheric pressure. Recent studies reported the beneficial outcomesof NTAPP including wound healing, activation of immune cells, and proliferation of mesoderm-derived adult stem cells inhuman. Therefore, to evaluate the effects of NTAPP on human deciduous dental pulp fibroblast like cells (hDDPF), we examined
the appropriate conditions of NTAPP exposure on hDDPF, and evaluated cell proliferation, and the mRNA expressions that play
key functions in maintaining the pluripotency of stem cells.Methods:Cells were obtained from the noncarious deciduous incisor
at Osaka Dental University Hospital. All experiments were approved by the Ethical Committee of Osaka Dental University. We
used the helium-based NTAPP device and cells were exposed to the indicated dose (2.7 standard liter/min [slm], 20 voltage[V]).
The distance between the device and cells was fixed to 20 mm. Cell proliferation was evaluated by a CellTiter96 Aqueous One
Solution Cell Proliferation Assay and gene expression analysis was performed using a Step One Plus system.Results:NTAPP
for 20 seconds per hour for 3 times efficiently accelerated the proliferation of hDDPF and further exposure reduced the cellproliferative capacity. The relative mRNA expressions of Oct4, Sox2, and Nanog in NTAPP-exposed cells were increased 3
days after exposure, when compared to unexposed control cells.Conclusion:NTAPP can be an efficient tool for expanding the
population of hDDPF in vitro for stem cell therapy and regenerative medicine.

Symposium II

072:

Poster Presentation

─ 109 ─073:

Effect of Lithium Carbonate on the Healing of Apical Periodontitis
T. KAGIOKA, S. ITOH, H. NARUSE, Y. ITO, M. HAYASHI
Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, Suita, Japan

Objective:We have developed the bioactive root canal medicament which activates immune responses and bone metabolism.
In vivo experiments using the rat root canal treatment model showed that lithium carbonate (Li2CO3) promoted the healing of
periapical lesions. The aim of this study is to identify the minimum effective concentration of Li2CO3 and verify the safety during
application of Li2CO3 into root canal.
Methods:The mandibular first molar pulp of 10-week-old Wistar rat was exposed. After 4 weeks from the pulp exposure, fourconcentrations of Li2CO3 (1%, 0.1%, 0.01%, and 0.001%) were applied into the root canals. After 7, 14, 21, and 28 days, thevolume of the periapical lesions were measured by micro-CT.
To monitor the blood concentration of Li+, rats were divided into two groups. One group is the application of Li2CO3 into root
canals, the other is the systemic administration of Li2CO3. Blood samples were collected at 1, 3, 6, 12, 24, 48, and 72 hours, andmeasured Li+ concentration.
The study was approved by the research Ethics Committee of the Osaka University, Suita, Japan, and all experiments were
performed according to the guidelines related to animal care (AD-26-011-0).
Resuts:There was no significant difference in the volumes of the periapical lesions between four concentrations at 7, 14, and 21
days. At 28 days, the volume of 0.001% Li2CO3 was significantly larger than other concentrations.
As a result of the blood concentration monitoring, the systemic administration showed transient increase in the bloodconcentration of Li+. On the contrary, in case of the application of Li2CO3 into root canal, there was no increase of Li+.
Conclusion:The experiment indicated that Li2CO3 was not sufficiently effective at the concentration of lower than 0.001%. In
addition, we showed that the application of Li2CO3 into root canal is safe.

074:

Large-conductance Ca2+-activated K+ Channels in Human Cementoblasts
S. KAMATA, M. KIMURA, Y. SHIBUKAWA, S. YAMASHITATokyo Dental College

Objective: Cementum, which is formed by cementoblasts, provides an attachment site for collagen fibers to fix the teeth into
the alveolar bone. Ionic signaling associated with cell membrane regulates various physiological and pathological processes
in the cell, but their properties in cementum forming cells have yet been remained be clarified. The purpose of this study
was to examine the biophysical and pharmacological properties of currents generated by ion channels expressed in humancementoblasts (HCEM).Methods: We measured ionic currents using whole-cell patch-clamp recording. Krebs solution wasused as a standard extracellular solution (ECS). Standard intracellular solution (ICS) was composed followings (in mM) ;140
KCl, 10 NaCl and 10 HEPES. We prepared Cs-ICS solution by equimolary replacing K+ in the ICS with Cs+. We used non-selective
K+ channel blocker TEA and Ca2+ -activated K+ channel blocker IbTX, apamin and TRAM-34 were added to the ECS.Results:
Depolarizing steps from holding potential (Vh) of -70 mV with 10 mV increments evoked outward and inward currents under
the ECS/ICS condition. Under the condition of Cs-ICS/ECS, the outward current almost disappeared. Application of TEA and
IbTX, reduced the outward current amplitude in the ECS/ICS condition. Apamin and TRAM-34 had no effect on it. The reversal
potential was measured by recording the tail current, and the date were fitted to the Goldman-Hodgkin-Katz equation. The
results showed that K+ and Na+ permeabilities were contributed to the outward current.Conclusion: The results suggested that
cementoblasts express large-conductance Ca2+-activated K+ channels. The currents via the Ca2+-activated K+ channels werecarried by K+ conductance with background Na+ conductance.

─ 110 ─

Activation of CGRP receptors increased intracellular cAMP level in odontoblasts
N. SAITO, M. KIMURA, H. MOCHIZUKI, K. KOUNO, M. ANDO, S. OHYAMA, T. ICHINOHE, Y. SHIBUKAWA
Tokyo Dental College, Tokyo, Japan

Greeting
Special Lecture

Objectives : Our previous studies suggested that Ca 2+ signaling in odontoblasts is involved in dentin formation and generationof dentinal pain. In the studies, we have reported the expression of transient receptor potential vanilloid subfamily member 1(TRPV1) channels and cannabinoid 1 (CB1) receptors in odontoblasts, and functional crosstalk between them. In odontoblasts,
increase in intracellular Ca 2+ concentration induced by TRPV1 channel activation secretes endocannabinoids. We also
demonstrated that cyclic AMP (cAMP) regulates CB1 receptor-TRPV1 channel crosstalk. These results suggest that cAMP may
participate in dentin formation and dentinal pain generation. However, the detailed intracellular cAMP signaling pathway inodontoblasts and the role of cAMP in odontoblast function remain unclear. In this study, we examined the cAMP signalingelicited by activation of adenylate cyclase or Gs protein-coupled receptors in odontoblasts.Methods : Odontoblasts were
acutely isolated from the incisors of newborn Wistar rats. Odontoblasts were cultured in α-MEM containing FBS for 24-36
hours, and then we added mNeon Green-based cAMP sensor. After culture for 24 hours, intracellular cAMP level was measured
from odontoblasts.Results : In the presence of extracellular Ca 2+, application of forskolin, an adenylate cyclase activator, dosedependently increased intracellular cAMP level in odontoblasts. The increases were decreased by repeated application of
forskolin. In the presence of extracellular Ca 2+, application of CGRP, a CGRP receptor agonist, increased intracellular cAMPlevel in odontoblasts. The increases were significantly inhibited by application of a selective CGRP receptor antagonist or an
adenylate cyclase inhibitor in odontoblasts.Conclusion : These results suggested that activation of adenylate cyclase increased
intracellular cAMP level in odontoblasts. We also showed expression of CGRP receptors in odontoblasts. In addition, theseresults indicate that CGRP receptor activation increased intracellular cAMP level by activation of adenylate cyclase.

Keynote Lecture075:

Symposium I

Plasma membrane Ca2+-ATPase regulates dentin formation and mineralization.
H. MOCHIZUKI, M. KIMURA, S. OHYAMA, K. KOUNO, M. ANDO, Y. SHIBUKAWA
Tokyo Dental College

Rising Scientist Session
Poster Presentation

─ 111 ─Symposium III

In odontoblasts, the control of intracellular Ca2+ concentration is important in driving their cellular function, dentinogenesis
and sensory transduction generating dentinal sensitivity. The intracellular Ca2+ level is regulated by Ca2+ influx, andmobilization as well as extrusion through plasma membrane Na+-Ca2+ exchanger (NCX) and/or plasma membrane Ca2+-ATPase(PMCA). We previously elucidated functional coupling mechanism between transient receptor potential channels and NCX1 andNCX3 in odontoblasts. On the other hand, Linde et al. (1995) revealed that odontoblasts express PMCA. However, the detailed
expression pattern of PMCA, its pharmacological properties and the roles in dentinogenesis remain unclear. Therefore, in thisstudy, we investigated the mRNA expression pattern of PMCAs, and effect of PMCA activity on mineralization mechanism inhuman dental pulp cells showing odontoblast differentiation (HOB cells). We also examined the pharmacological propertiesof PMCA. We measured intracellular free Ca2+ concentration ([Ca2+]i) by fura 2 fluorescence. The expression of PMCA14 mRNAs in HOB cells was demonstrated by real-time reverse transcription polymerase chain reaction. We also analyzed
mineralization efficiencies by alizarin red and von Kossa staining. We observed a little expression of PMCA2 mRNA. In thepresence of extracellular Ca2+, the application of hypotonic or alkaline (pH8) solution transiently increased [Ca2+]i in acutely
isolated rat odontoblasts. During hypotonic or alkaline solution-induced [Ca2+]i increase, the Ca2+ exclusion efficiency wasdecreased by PMCA inhibitors. PMCA inhibitors also reduced stainability using alizarin red and von Kossa stains in HOB 28 days
culture, indicating that inhibition of PMCA suppressed mineralization levels by HOB cells. These results suggest that PMCA14 participate in maintenance of the intracellular Ca2+ concentration in odontoblasts. In addition, they suggest that PMCA inodontoblasts is involved in dentinogenesis under the normal physiological and the pathological condition following mechanicalstimulation by hydrodynamic force inside dentinal tubules or alkaline stimulation by application of high pH dental materials toodontoblasts.

Symposium II

076:

077:

Functional expression of mechanosensitive ion channel in mouse osteoblasts
S. NAGAI1, K. KITAMURA3, M. KIMURA2, Y. SHIBUKAWA2, H. YAMAMOTO3, A. KATAKURA1
1

Department of Oral Pathobiological Science and surgery, Tokyo Dental College, Tokyo, Japan, 2Department of Physiology, Tokyo Dental
College, Tokyo, Japan, 3Department of Histology and Developmental Biology, Tokyo Dental College, Tokyo, Japan

Objectives: Mechanical stress is one of the important regulatory factors in bone homeostasis. Although mechanicalstimulation to osteoblasts elicits an increase in intracellular free Ca2+ concentration ([Ca2+]i), their detailed mechanism of themechanosensitive processes remains unclear. The present study investigated pharmacological properties of direct mechanicalstimulation-induced [Ca 2+]i response in osteoblasts. In addition, we examined the immunohistochemical expression of
mechanosensitive channels.Methods: Mouse osteoblast-like cells (MC3T3-E1) were cultured in 5% CO2 at 37 °C, and loaded
fura-2/AM for 1 hr. The standard extracellular solution was Krebs solution, and we measured [Ca2+]i responses during; 1)application of hypotonic Krebs solution or Yoda1 solution, 2) direct mechanical stimulation with a glass micropipette to thesingle cells with or without extracellular Gd3+, GsMTx4, RN1734, HC030031 or Clemizole. We also studied immunofluorescenceof TRPV4, Piezo1 and Piezo2 channel proteins to identify their morphological localization.Results: An application of hypotonic
Krebs solution and Yoda1 solution increased [Ca2+]i in the osteoblasts. Repeated application caused significant desensitizing
effects on the [Ca2+]i increase. When direct mechanical stimulation was applied, [Ca2+]i was increased, but was not showedsignificant desensitizing effects. Extracellular Gd3+, GsMTx4 and RN1734 reversibly inhibited mechanical stimulation-induced[Ca2+]i increases. Immunofluorescent staining showed positive reaction of Piezo1 and TRPV4.Conclusions: These results
suggested that Piezo1 and TRPV4 channels were involved in the mechanosensitive machinery of MC3T3-E1.

078:

Activation of mechano-sensitive ion channels in cancer cells establishes paracrine network via endothelin
signaling
M. ISHIZAKI1, M. MATSUNAGA1, T. YAZAKI1, N. SAITOH1, S. OHYAMA2, M. KIMURA2, Y. SHIBUKAWA2, T. ICHINOHE1
1
Department of Dental Anesthesiology, Tokyo Dental College, Tokyo, Japan, 2Department of Physiology, Tokyo Dental College, Tokyo,
Japan

Intercellular cell-cell communication of cancer cells relates to their metabolism such as, growth, progression, migration andmodulation of pain. Both cancer cells and cancer-associated cells have been reported to overexpress endothelin and its
receptors within cancer tissue, the autocrine and paracrine effects of endothelin axis involve in proliferation, resistance toapoptosis, migration and invasion. The detailed causes and mechanisms in releasing endothelin still remain unclear, however.
We, thus, investigated the mechanical sensitivity of rat squamous cell carcinoma cells and their paracrine communication
by diffusible transmitter(s) released from mechanically stimulated cells to examine endothelin system involved in cancer
metabolism.Rat squamous cell carcinoma cell lines (SCC-158) were used for this study. We measured intracellular free Ca2+
concentration ([Ca2+]i) by fura-2/AM. [Ca2+]i changes were recorded during direct mechanical stimulation to single SCC-158 cell.
For direct mechanical stimulation, glass micropipette was used to compress the cell membrane to 8 μm for 4 sec. This wasdone by holding the pipette for 22 sec. During direct mechanical stimulation to SCC-158, we could observe transient [Ca2+]
increases. Transient [Ca2+]i increases were also observed in neighboring cells to the stimulated SCC-158. Application of 10iμM Gd3+ and 1 μM GsMTX4 inhibited mechanical stimulation-induced [Ca2+]i increases in stimulated SCC-158. Application of
1 μM BQ-123 (endothelin A receptor inhibitor) did not inhibit [Ca2+]i increases in stimulated SCC-158 but did those in theirneighboring cells.We suggest that SCC-158 express piezo-1 channel. Activation of piezo-1 channels induced endothelin releasefrom the stimulated cells. Released endothelin then activates endothelin A receptors in the neighboring SCC-158. The results
suggested that intercellular paracrine communication among cancer cells might play an important role in cancer metabolism byendothelin signaling.

─ 112 ─

Mechanical stimulation-induced intercellular communication in trigeminal ganglion neurons
T. YAZAKI1, M. ISHIZAKI1, M. MATSUNAGA1, S. OHYAMA2, H. KURODA3, M. KIMURA2, Y. SHIBUKAWA2, T. ICHINOHE1,2
1
Department of Dental anesthesiology, Tokyo Dental Colledge, Tokyo, Japan, 2Department of Physiology, Tokyo Dental Colledge, TokyoJapan, 3Graduate School of Dentistly Department of Critical Care Medicine and Dentistly, Kanagawa Dental University, Kanagawa Japan

Greeting
Special Lecture

Although paracrine communication between neurons and non-neuronal cells has been well described, there has been a little
report on the intercellular communication between neurons. We have previously examined intercellular communication
between trigeminal ganglion (TG) neurons by patch-clamp recordings. When we applied mechanical stimulation to the single TG
neuron, we could record inward current from a stimulated TG neuron, while could not record any responses from neighboring
TG neuron. In this study, we thus aimed to clarify whether metabotropic receptor activation was capable to establish interneuron communication by diffusible factor(s) released from mechanically stimulated TG neuron or not. For this purpose, wemeasured intracellular free Ca2+ concentration ([Ca2+]i) from mechanically stimulated TG neurons and its neighboring neurons.
TG cells were dissected and isolated from 7-day-old Wistar rats under anesthesia and primary cultured (5% CO2, 95% Air,37°C) for 48 hrs. Fura-2, which is a Ca2+ fluorescent indicator, was loaded into the cells (1 hr), and [Ca2+]i was recorded fromthe fluorescence intensity (at 510 nm) ratio of the excitation wavelengths of 340 nm and 380 nm.When the TG neurons were
pushed down by 12 μm using a glass micropipette, we could measure [Ca2+]i increases simultaneously from stimulated neurons
and neighboring neurons. In addition, the increase in [Ca2+]i did not show desensitization effects even after repeated direct
stimulation. In the absence of extracellular Ca2+, [Ca2+]i increases were not observed. These results suggest that neurons arecapable to receive mechanical stimuli and release diffusible intercellular transmitters to establish functional intercellularcommunication with surrounding neurons.

Keynote Lecture079:

Symposium I

Piezo1 channel activation evokes mechanosensitive Ca2+ signaling in human odontoblast
M. MATSUNAGA1, M. KIMURA2, M. ISHIZAKI1,2, T. YAZAKI1,2, S. OHYAMA2, Y. SHIBUKAWA2, T. ICHINOHE1
1

Dental Anesthesia, Tokyo Dental College, 2Physiology, Tokyo Dental College

Symposium III
Rising Scientist Session

Odontoblasts play critical roles in dentinogenesis and sensory transduction by stimuli applied to the dentin surface. In aprevious study, we reported that direct mechanical stimulation induced Ca2+ influx through mechanosensitive transient
receptor potential channels in acutely isolated rat odontoblasts. In addition, the Ca2+ signaling in odontoblasts participate inreactive dentin formation. On the other hand, we demonstrated, in the trigeminal ganglion neurons-odontoblasts coculture
system, suppression of inward current in neighboring trigeminal ganglion neurons following mechanical stimulation to single
odontoblasts by mechanosensitive piezo1 channel antagonist. However, in human odontoblasts (HOB) cells, the cellularresponse elicited by mechanical stimulation, the detailed properties and direct evidence showing expression of piezo channel
remain unclear. In the present study, we investigated mechanical stimulation-induced intracellular Ca2+ signaling and piezochannel expression in HOB cells. Intracellular free calcium concentration ([Ca2+]i) in HOB cells was measured using fura-2
fluorescence. In the presence of extracellular Ca2+, mechanical stimulation transiently increased [Ca2+]i in both mechanicallystimulated HOB cells and neighboring HOB cells. The increases were not desensitized by repeated stimulation. Membrane
deformation using a low-osmotic solution in HOB cells induced transient increases in [Ca2+]i. The increase was inhibited byapplication of Gd3+, a non-selective piezo channel antagonist. An application of Yoda1, a selective agonist of piezo1 receptors,
transiently increased [Ca2+]i in HOB cells, which was suppressed by extracellular Gd3+ and Dooku1, a selective piezo1 channel
inhibitor. These results showed that mechanical stimulation evoked intracellular Ca2+ signaling in HOB cells, and the Ca2+
signaling established intercellular odontoblast-odontoblast communication. The results also suggest that piezo1 channels are
expressed in HOB cells.

Symposium II

080:

Poster Presentation

─ 113 ─081:

Effects of preemptive analgesia with intravenous acetaminophen on postoperat ive pain relief in patients
undergoing third molar surgery: a prospective, single-blind, randomized controlled trial
K. KANO1,2, K. KAWAMURA3, T. MIYAKE3
1

Graduate School of Dentistry, Osaka Dental University, Osaka, Japan, 2Department of Dentistry and Oral Surgery, Uji Takeda Hospital,
Kyoto, Japan, 3Department of Preventive and Community Dentistry, Osaka Dental University, Osaka, Japan

Objectives: The efficacy of preemptive analgesia in managing postoperative pain is still controversial. The aim of this study
was to compare the efficacy of intravenous (IV) acetaminophen given before or immediately after the surgical extraction of
an impacted mandibular third molar. Methods: This prospective, randomized clinical trial included 120 patients. The patientswere assigned to receive one of three different protocols: the pre-treatment group (pre-group) received 1000 mg of IV
acetaminophen 20 min before the surgery, the post-treatment group (pro-group) received 1000 mg of IV acetaminophen after
the surgery, and the no-treatment group (control-group) received nothing. Rescue analgesic medicine (60mg loxoprofen) was
issued to each patient with instructions on self-administration if needed. The following data on rescue medication usage wasobtained for a 17 hour period following the surgery: (1) the time of the initial loxoprofen treatment and (2) the total amountof loxoprofen consumption. Visual analog scale (VAS) pain scores were obtained from all patients 1, 2, 3, 4, 5 and 15 h after thesurgery. Results: There was no significant difference between the three groups in each fixed time interval as measured by the
VAS. However, the pre-group demonstrated a significantly lower consumption of rescue analgesic and a later time for the initialadministration. Conclusions: Administering IV acetaminophen before third molar surgery provides more effective pain control
in contrast to postoperative administrations and no treatments.

082:

Diagnostic and Prognostic Applications of Artificial Intelligence-based Radiology in Head and Neck Region
M. Poorsattar1, A. Poursattar Bejehmir2
1

Private section, San Antonio, Texas, UNITED STATES, 2Private Section, Toronto, Ontario, CANADA

Objectives: Since the introduction of Artificial intelligence (AI) in early 50' defined as "a field of science and engineering
concerned with the computational understanding of what is commonly called intelligent behavior, and with the creation of
artifacts that exhibit such behavior", it has witnessed enormous improvement and become more sophisticated and has beenused more widely.Methods: This presentation is aimed to elaborate on the most recent dentistry related applications of AI
published in literature as a non-systematic narrative review.Results: Machine learning (ML) as a subdivision of AI has been
implemented as Genetic Algorithm (GA), the Artificial Neural Network (ANN) to predict the outcome of a genetic disorder ortreatment plan aiding scientists and clinicians improve the medical and surgical interventions. A subfield of ML, deep learning(DL) and in particular, convolutional neural networks (CNN) has extended horizons for automatic segmentation of cancerous
lesions in head and neck region with promising sensitivity and specificity. CNN is also applied in growth prediction, radiologic
anatomic landmark detection, radiologic periodontal bone loss (PBL), caries detection, intraosseous bone lesions, forensic
dentistry radiology and metastasis prediction based on CT, CBCT, MRI and histology inputs.Conclusions: According to existing
accuracy rate of AI based modeling, an expanding role of such a paraclinical aid for clinical decision is expected in the medical
and dental fields at both preclinical and clinical levels.

─ 114 ─

Revolutionalized Concept of Digitalizing Dental Treatment Contents using Machine Learning
S. OKA1, K. NOZAKI2, M. HAYASHI1
1

Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, Osaka, Japan, 2Division for
Medical Information, Osaka University Dental Hospital, Osaka, Japan

Greeting
Special Lecture

Objectives: Our current study aims at developing a method to encode the treatment and estimate the content of the treatment
from the video footage of the tray on which instruments are placed during a dental treatment.Methods: An image recognition
algorithm was developed using YOLOv3 to recognize 23 types of dental instruments and hands. Image recognition was
performed on all frames of the video of the tray on which instruments were placed during 65 treatments, which consisted offour kinds of treatment contents, and encoded into 24-dimensional vectors with the number of existences of each instrument
and hand as elements, and converted them into time series data. One hundred frames were randomly selected from the 65
videos and the average encoding accuracy was determined from the percentage of correct responses of the elements of the
24-dimensional vector representing each frame. The time series data was divided by the presence of a hand, and the averagetime series data consisting of the average value of the vectors in each section was generated. We trained 1-3 layers of Long
Short-Term Memory (LSTM) neural networks with 2 types of time series data as input and 4 types of dental treatment contents
as output for 500 epochs, and performed leave-one-out cross-validation every 5 epochs, and obtained the highest accuracy wascompared as the accuracy obtained in each neural network.Results: The average coding accuracy was 81.2%.The accuracies ofthe dental treatment contents classification in the 1-3 layers of LSTM were 66.2%, 70.8% and 67.7% when time series data wereused. When average time series data were used, the accuracies were 67.7%, 70.8%, and 69.2%, respectively.Conclusions: We
developed a method for encoding dental treatment. From the obtained codes, the contents of the treatment could be classified
with about 70% accuracy.

Keynote Lecture083:

Symposium I

Evaluation of simulation training courses on basic clinical skills for geriatric dentistry for trainee dentists
H. TAKETA1, T. YOSHIDA2, A. YABE1, N. SHIOTSU1, T. KONO1, H. SHIRAI1, Y. TORII1
1

Comprehensive Dental Clinic, Okayama University Hospital, Okayama, Japan., 2Center for Education in Medicine and Health Sciences(Dental Education), Okayama University, Okayama, Japan.

Symposium III
Rising Scientist Session

Objectives: Geriatric dentistry is becoming the most important issue for delivering dental care as Japan transforms into asuper-aged society. Although dental care for older adults requires basic dental treatment skills, trainee dentists, who havejust acquired a dentist license, are often inexperienced in basic dental care skills. Therefore, we provided a simulation training
courses for basic dental clinical skills for geriatric dentistry for trainee dentists. The purpose of this study was to evaluate thesimulation training courses using a questionnaire.Methods: We included 43 trainee dentists enrolled in a 1-year postgraduate
clinical training course at Okayama University Hospital in 2019. Simulation training courses for basic dental clinical skills such as
tooth preparation for various dental restorations, root canal treatment, and oral cleaning for geriatric patients were provided.
We administered a questionnaire survey and statistical analysis to investigate the practice environment and effectiveness of
simulation training.Results: Almost all trainee dentists thought that the simulation training for preparation and root canaltreatment would be useful for clinical practice, although more than half thought that the number of practice sessions forroot canal treatment was insufficient. A statistical analysis revealed that the trainee dentists increased their knowledge ofdental care for older adults after the simulation training course for geriatric dentistry. In addition, the trainee dentists became
interested in the dental treatment of older adults and began to think about contributing to dentistry for older adults in the
future.Conclusions: This questionnaire results showed that the trainee dentists felt that the simulation training was useful forclinical practice. It was also suggested that we could perform a higher quality training by improving the training environment.

Symposium II

084:

Poster Presentation

─ 115 ─

085:

Needs Of Dentists During The Covid-19 Pandemic In Nepal
Y. HARADA1, D. PRAJAPATI2, H. IWASHITA1, T. SUGISHITA1
1

International Affairs and Tropical Medicine, Tokyo Women's Medical University, 2Community and Public Health Dentistry, Dhulikhel
Hospital, Kathmandu University School of Medical Science

Objective: During the Coronavirus disease (Covid-19) pandemic, Nepal decided to continue the dental service with caseprioritization and infection control. Because the dental setting is a high risk for cross-infection, the needs of dentists should be
identified and addressed. Recent studies illustrated public and private sectors have different practice environments, thus theirneeds might be different. We aimed to assess the needs of dentists by the practice sectors during the Covid-19 pandemic in
Nepal.Methods: A cross-sectional online questionnaire survey was conducted from 28th July to 7th August 2020 by distributing
the questionnaire through emails and social networking services. It had five sections; basic characteristics, behavior, material
availability and affordability, economic and psychological impact, and training and supports. The answers were stratified by
the practice sectors (public hospitals and private clinics). Logistic regression was carried out to calculate the odds ratios (OR) of
each answer based on the practice sectors, adjusting for sex and age.Results: 352 dentists (137 males and 215 females) were
included in the analysis. 146 (41.2%) and 200 (56.8%) dentists worked for public hospitals and private clinics, respectively.
Fewer dentists in private clinics experienced a lack of personal protective equipment than public hospitals (OR=0.3; p=0.001).
Conversely, private clinics had a larger economic negative impact; more dental clinics were permanently closed (OR=2.3;
p=0.015) and decreased salary more than 80% (OR=3.5; p<0.001) than public hospitals. Additionally, more dentists in private
clinics received Covid-19 training from social media than public hospitals (OR=2.3; p=0.002). Overall, fewer dentists in private
hospitals requested material support (OR=0.5; p=0.002) but demanded more for financial (OR=2.3; p=0.010) and technicalsupport (OR=2.2; p=0.012) than dentists in public hospitals.Conclusion: Dentists working for public hospitals and private clinics
in Nepal had different needs during the Covid-19 pandemic and these needs should be addressed accordingly.

086:

Oral conditions matter for general health of community-dwelling elderly population
Y. NAKAI1, Y. NAGATANI1, M. OZAKI2, K. OHUCHI2, H. KINOSHITA2, A. HIRANO2, T. YANAGAWA2
1

Department of Dental Hygiene, University of Shizuoka Junior College, Shizuoka, Japan, 2Shizuoka Dental Association, Shizuoka, Japan

Objectives: Deterioration of oral function and general health might be linked in the elderly people, but population-based
studies are scarce previously. This study described the oral conditions including its functional aspects, and examined theassociation between oral conditions and systemic disease in the elderly population. Methods: The subjects consist of 20052
75-year-old, and 12410 80-year-old individuals who were dwelling in Shizuoka prefecture, Japan, and participated in the oral
health check-ups between 2016-2018, which was provided as a public health service. Number of remaining teeth, carious
and periodontal status, masticatory ability, tongue movement, the repetitive saliva swallowing test, mouth dryness, and oral
hygiene were examined by the experienced dentists. Information regarding the self-rated oral functions and the presence ofsystemic disease was collected using the questionnaire which the subjects brought to their dentists when visiting for checkups. Data on the subjects' body mass index (BMI) and annual medical and dental expenses were obtained from the Shizuoka
association of long-term care medical insurance system. Objective oral frailty score was calculated from the results of clinicalexamination, and Perceived oral frailty score was from the self-rated assessment of the questionnaire. Results: 73.0% and62.1% of the 75- and 80-year-old subjects had 20 or more teeth, respectively. 41.2% and 53.2% showed objective oral frailty(score≥1), and 54% and 56.5% showed perceived oral frailty (score≥1). Objective oral frailty score was positively correlatedwith perceived oral frailty score, number of present systemic diseases, annual medical and dental expenses. It was negatively
correlated with number of caries-free teeth, number of remaining teeth, and BMI.Conclusions: The deterioration of oral
function was associated with greater risks of having systemic disease and having to pay higher medical and dental expenses inolder age. Increasing BMI, retaining more teeth without caries could be important for its prevention. (Support by JSPS KAKENHI
18K02250)

─ 116 ─Comparative study of plaque removal effect on Japanese commercial toothbrushes.
C. HSU, K. SHINADA
Department of Preventive Oral Health Care Sciences, Tokyo Medical and Dental University, Tokyo, Japan

Objectives: There are so many shapes, sizes, and styles of toothbrushes on the market. We may know comparative effects
about that. This study aims to evaluate the plaque removal effect of commercially various toothbrushes in vitro.

Conclusions: The different designs of the commercial toothbrushes like hardness, planting density, tip shape, etc. affected theplaque removal rate. Particularly, the plaque remaining by the ultrafine toothbrushes was large, and there were significant
differences statistically between other toothbrushes.

Special Lecture

Results: As for the plaque removal rate in all parts, the mountain-shape cut bristle toothbrush had the highest removal rate
(61.2%). On the other hand, the ultrafine bristle toothbrush had the lowest (17.4%) with significant differences between othertoothbrushes. These designs, rough surface processing type (59.1%), spherical bristle type (59.1%), and the diamond shape
type (59.7%) had better plaque removal effect, although there was no significant difference in this experiment. Nevertheless,almost toothbrushes had more than 50% of plaque remained in the tooth adjacent surface. It seems necessary to use otheroral cleaning tools such as dental floss or interdental brush to remove plaque in adjacent surfaces.

Greeting

Methods: The toothbrushes were selected Nikkei telecom top-selling products and other different head designs, totally used 11
types. The brands were Clinical Advantage®, System Toothbrush®, Between Lion®, Gum Dental Brush®, Clear Clean Toothbrush®,
and Ruscello Toothbrush®. Using 6 (16, 21, 24, 36, 41, and 44) artificial teeth (NISSIN) setting on the dental model, the brushingmethod was performed for 10 seconds per site with keeping pressure of 150g. The outcome was the removal rate of artificial
plaque (NISSIN). Image analysis using software ImageJ was calculated from the remaining area of plaque, by taking photographs
before and after brushing. The statistical analysis was used SPSS22.0 (IBM) for comparing.

Keynote Lecture087:

Symposium I

Comparing the oral health-related quality of life of people with diabetes and people without diabetes at
a Tertiary Hospital in Nigeria
N. A. Ilochonwu
Preventive Dentistry, University of Port Harcourt, Choba, Port Harcourt, Rivers State, NIGERIA

Symposium III
Rising Scientist Session

Objectives: The bidirectional relationship between diabetes mellitus and periodontal disease may negatively influence theoral health quality of life of diabetics. The study aims to compare the oral health quality of life of diabetics and non-diabetics.
Methods: A descriptive cross-sectional study involving 115 people with diabetes seen at the Endocrine Clinic and 115 nondiabetics at Dental Centre UPTH. A self-administered questionnaire was employed for this study. The people with diabetes wereselected by systematic random sampling method, and the non-diabetics were matched for age and sex from the Oral Diagnosis
unit. Data analysis was done with IBM SPSS Statistics version 25. Chi-square and t-tests were done to test for differences andlevel of significance at 0.05.Results: There were 44 (38.3%) males, 71 (61.7%) females in each group and the mean ages were
56.04 ± 11.67 years for non-diabetics and 55.97 ± 11.48 years for diabetics. Of the 14 subdomains of OHIP-14, only the ‘hadto interrupt meals’ was significantly different between diabetics 17 (14.8%) with impact and non-diabetics 29 (25.2%) without
impact (p=0.048). the summated OHIP-14 impact was 27 (23.5%) for diabetics and 32 (27.8%) for non-diabetics (p=0.450).
whereas the non-diabetics were found to have slightly higher impacts in nine (64.3%) out of the 14 subdomains of OHIP-14,
people with diabetes had 5 (35.7%).Conclusions: The oral health impact of non-diabetics was not significantly different fromthat of the diabetics. It is imperative to refer people with diabetes for routine oral evaluation and intervention.

Symposium II

088:

Poster Presentation

─ 117 ─089:

Survey Of Smile Satisfaction And Desired Treatments Among Medical And Dental Students.
T. Khatri1, S. Butt2, A. Tufail1, R. Fatima1, Z. Irfan1
1

University of Health Sciences, Karachi, Sindh, PAKISTAN, 2University, Karachi, Sindh, PAKISTAN

Objectives: The purpose of this study was to evaluate the factors prompting students’ satisfaction with their own smile andtheir willingness to opt for different treatments to improve their dental appearance.Methods: A cross sectional questionnaire
based study was conducted among 400 undergraduate medical and dental students from different universities of Karachi,
Pakistan.Only the undergraduate medical and dental students were included while the postgraduate students were excluded.
Data was piled up and analyzed by SPSS version 22. A questionnaire was filled by the students responding to dental problems or
conditions with which they are not happy and the oral/dental treatments they would opt.Results: The participating candidates
were predominantly female(81.5%). The data analysis showed (30.8%) of the students were not happy with their generaldental appearance whereas a greater percentage was dissatisfied with their tooth color(37.8%). Tooth whitening was the mostdesirable treatment (59.8%) followed by orthodontic treatment(32%). Dentures were the least popular option among theyoung students with only (1.3%).Survey showed that a notable percentage of the population (35.5%) were not willing to bear
the expense of the treatments.Conclusions: Majority of the participants were satisfied with their general dental appearancewith higher percentage unhappy with their tooth color.Generalized spacing being endemic in Asian population was disregardedby (14.2%) of the students while (19.3%) complained of space among central incisors only. Female students were more agitatedconcerning their appearance. Out of two student groups, smile assessment was better discerned by dental students.

─ 118 ─

Author Index-演者索引
A

FUJITA, T., 039

I

Abdou, A., 006, 047

FUKUDA, T., 041, 044

ICHINOHE, T., 075, 078, 079, 080

ABE, Y., 055

FUKUSAKI, E., 028

IDEGUCHI, H., 049

ABIKO, Y., 040, 052, 071

FUNATO, N., 058

IKAWA, S., 025

AL BOUGHA, S., 050

FURUSAWA, M., 071

IKEDA, H., 007, 013

ALI, S., 024

FUSEJIMA, F., 001, 002, 005, 011,

IKEZAKI, K., 059
Ilochonwu, N. A., 088

065

AMANO, A., 028, SI-4
ANDO, M., 075, 076

G

IMAI, K., 031

ANDO, T., 053

GONG, S., 024

IMAMURA, K., 038

AOKI, S., 072

GOTO, K., 020, 021

IMAZATO, S., 017

AOYAGI, H., 049

GRENIER, D., 016

INABA, K., 015, 022

ARIMA, E., 011, 065

H

Irfan, Z., 089

ARITA, K., 072

HAILING, H., 069

ISEKI, S., SII-3

ARORA, P., 043

HAMADA, N., 015, 022

ISHIHARA, K., 019, 030, 038

ASAUMI, H., 021

HAMBA, H., 008

ISHIZAKI, M., 078, 079, 080

Azuma, T., 001

HARA, E.S., 062, 067

ISHIZUKA, H., 008

B

HARADA, K., 072

ISLAM, S., 052

Bejehmir, 082

HARADA, Y., 085

ITO, C., 071

C

HASEGAWA, Y., 029

ITO, S., 032

CHIBA, I., 052

HASHIMOTO, K., 070

ITO, Y., 025

CHIBA, M., 055

HATAKEYAMA, J., 016

ITO, Y., 073

D

HAYASHI, C., 041, 044

ITOH, S., 073

Den Besten, Pamela, G

Hayashi, M., 009

IWASHITA, H., 085

DENG, F., 017

HAYASHI, M., 010, 069, 073, 083

IWASHITA, M., 045

DUFOUR, D., 024

HAYASHI, M., 045

IWASHITA, M., 046

E

HIGASHIHORI, N., 056

IWATA, T., 036

EGOSHI, T., 004

HIGUCHI, S., 012

IWAYAMA, T., 046

EGUSA, H., 057

Hiraishi1, N., 006

K

F

HIRAMINE, H., 015

KADOTA, T., 033

FARAHAT, M., 067

HIRANO, A., 086

KAGIOKA, T., 073

Fatima, R., 089

HIRANO, K., 002

KAIDA, K., 004

FUJIHARA, C., 046

HIRANO, K., 005

KAKU, M., 003

FUJII, M., 070

HIROFUJI, T., 016

KAMATA, S., 074

FUJII, S., 054

HOMMA, H., 035, 063

KAMIJO, R., 059, 061

FUJIMORI, K., 002

HSU, C., 087

KANO, F., RS-1
KANO, K., 081

FUJIMOTO, T., 054

─ 119 ─

KANO, S., 056

KOYANAGI, T., 036

MIZOGUCHI, T., SIII-4

KANO, T., SIII-2

KUBO, S., 004

MOCHIZUKI, H., 075, 076

Kariya, S., 001

KUBONIWA, M., 028

MORI, Y., 050

KARNTIANG, P., 007

KUNIOSHI, N., 062

MORIKAWA, T., 040

KATAGIRI, A., RS-2

KURAHASHI, A., 022

MORITA, H., 016

KATAGIRI, S., 036

KURODA, H., 079

MORIYAMA, K., 056

KATAKURA, A., 077

Kuroda, S., 047

MORIYAMA, K., 069

KATO, S., 065

KURODA, S., 064

MURAKAMI, S., 005

KAUSHIK, A., 068

KUSUBATA, M., 058

MURAKAMI, S., 046

KAWAI, S., 072

L

MURAMATSU, T., 008, 071

KAWAI, T., 025, 026

LAMONT, R., 028

MURATA, H., 004

KAWAKAMI, K., 041

Lamont, Richard J, KL-1N

KAWAMURA, K., 081

LAURIE, L. E., 058

NAGAI, N., 035

KAWASHIMA, N., 070

LEVESQUE, C., 024

NAGAI, S., 077

KAZI, G. A. S., 067

LIN, D.-J., 003

NAGAMATSU, H., 013

Khatri, T., 089

LIU, S., 051

NAGAMATSU, Y., 007, 013

KIKUCHI, Y., 030

LIU, Y., 017

NAGANO, K., 029

KIMURA, M., 074, 075, 076, 077,

M

NAGASAWA, Y., 032

MATAYOSHI, S., 018, 023

NAGATANI, Y., 086

KIMURA, N., 065

Matsuda, Y., 009

NAITO, K., 010

KINOSHITA, H., 086

MATSUDA, Y., 010

NAKA, S., 032, 034, 037, 060

KITA, D., 030

MATSUMOTO, S., 046

NAKADE, H., 024

KITAGAWA, H., 017

MATSUMOTO, S., 069

NAKAI, Y., 086

KITAMURA, K., 077

MATSUMOTO, T., 062, 067

NAKAJIMA, K., 043

KITAMURA, N., 065

MATSUMOTO-NAKANO, M.,

NAKAMURA, K., 008

KITAMURA, T., 018

020, 021, 032, 034, 037, 060

NAKAMURA, T., SII-4

KIYOSHIMA, T., 054

MATSUNAGA, M., 078, 079, 080

NAKANE, S., 038

KOBAYASHI, F., 071

MATSUOKA, H., 052

NAKANO, H., 050

KOBAYASHI, H., 012

MAYUMI, S., 028

NAKANO, K., 018, 023, 032, 033,

KOGA, C., 016

MCCULLOCH, C., 043

KOHNO, T., 017

MISAKI, T., 032

NAKAO, Y., 041

KOICHIRO, K., 039

MIYAI, Y., 037

NAKAO, Y., 044

KOJIMA, K., 063

MIYAKE, T., 081

Nakata, H., 047

KOKUBU, E., 030

MIYAMOTO, J., RS-3

NAKATA, H., 064

KOMATSU, K., 036

MIYAMOTO, Y., 059

NAKAYAMA, M., SI-2

KONER, R., 068

MIYAYOSHI, Y., 008

NARA, K., 070

KONO, T., 084

MIYOSHI, T., 027

NARUSE, H., 073

KOUNO, K., 075, 076

MIZOGUCHI, I., 055

NAWAL, R.R., 068

078, 079, 080

─ 120 ─034, 060

SHIBUKAWA, Y., 074, 075, 076,

NEGISHI, S., 061

P

NEMOTO, E., 042

Park, Joo-Cheol, SL

077, 078, 079, 080

NEMOTO, T., 036

PECHAYCO, R., 055

SHIGEMURA, N., SIII-1

NEZU, Y., 019

PENG, T.-Y., 003

SHIMIZU, H., 007, 013

NIHEI, T., 015

Poorsattar, M., 082

SHIMIZU, T., 012

NIIBE, K., 057

Poursattar, A., 082

SHIMMA, S., 028

NISHIBORI, M., 049

PRAJAPATI, D., 085

SHIMOE, S., 003

NISHIMURA, F., 041, 044, 045

Q

SHIMOGISHI, M., 036

NISHIMURA, Y., 045

QIU, Y.J., 066

SHIN, R., 025

NODA, S., 070

R

SHINADA, K., 014, 087

NOMURA, R., 018, 023, 032, 033

Rutt, S., 089

SHINJO, T., 045

NOZAKI, K., 083

RYU, M., 019

SHINODA, M., SIII-3

O

S

SHINTANI, S., 035, 063

OBA, S., SII-1

Sabbagh, A. A., 047

SHIOTSU, N., 084

OGAWA-GOTO, K., 058

SAITO, A., 038

SHIRAI, H., 084

OGAYA, Y., 033

SAITO, M., 042

SHIROTA, T., 059

Ogura, Hiroyuki, SII-4

SAITO, N., 075

Shohei, K., 047

Ohara, Naoya, SI-2

SAITO, T., 009, 066

SHUKUNAMI, C., SII-2

OHORI, Y., 057

SAITOH, N., 078

SINJO, T., 041

OHSHIMA, T., 025, 026

SAKAE, K., 029

SOENO, K., 004

OHTA, T., 040

SAKAGUCHI, Y., 011

SUEHIRO, Y., 023

OHUCHI, K., 086

SAKAI, Y., 026

SUGISHITA, T., 085

OHYAMA, S., 075, 076, 078, 079,

SAKANAKA, A., 028

SUZUKI, N., 016

SAKURAI, A., 035, 063

SUZUKI, S., 042

OKA, S., 083

Sakurai, M., 009

T

OKADA, M., 062

SANO, T., 045

TABATA, K., 034

OKAMOTO, M., 069

SANUI, T., 041, 044

TAGA, Y., 058

OKAWA, R., 060

SASA, K., 059

Tagami, J., 006

OKIJI, T., 070

SASAKI, H., 015, 022

TAIRA, Y., 004

OKUNO, M., 072

SASAKI, M., 015

TAKAHASHI, I., 050

Okuyama, K., 009

SATO, A., 042

TAKAHASHI, N., 051

OKUYAMA, K., 010

SATO, J., 040

TAKAHASHI, T., 055

OMAGARI, S., 016

SATO, S., 031

TAKAHASHI, Y., 069

OMINE, Y., 048

SATO, T., 022

TAKAI, R., 040

OMORI, N., 064

SAWA, Y., 039

TAKASHIBA, S., 049

OTA, T., 035

SHIBA, T., 036

TAKEDACHI, M., 046

OTSUGU, M., 018, 023

SHIBASAKI, M., 036

TAKESHITA, T., SI-1

OZAKI, M., 086

SHIBAYAMA, K., 030

TAKETA, H., 084

080

─ 121 ─

Takeuchi, Hiroki, SI-4

WATANABE, Y., 041, 044

TAKEUCHI, Y., 036

WATO, K., 032

TAKIZAWA, A., 055

Y

TALWAR, S., 068

YABE, A., 084

TAMAOKI, S., 039

YAKLAI, S., 055

TANAKA, A., 063

YAMADA, K., 016

TANAKA, M., 059

YAMADA, S., 042, 046

TANAKA, T., 025

YAMADA, T., 050

TANAKA, U., 041, 044

YAMAMOTO, H., 009, 010

TANASE, T., 063

YAMAMOTO, H., 077

TASAKA, A., 012

YAMAMOTO, S., 016

TAZAWA, K., 070

YAMAMOTO, T., 042

ThanNaing, S., 006

YAMAMOTO, T., 049

THIHA, P., 056

YAMANAKA, K., 011, 065

THOAI, K., 070

YAMASHIRO, K., 049

TOMETSUKA, C., 058

YAMASHITA, A., 045

TOMITA, K., 046

YAMASHITA, A., SII-5

TONOMURA, S., 034

YAMASHITA, S., 012

TORII, Y., 084

YAMASHITA, S., 074

TOYODA, M., 041

YAMATO, H., 041, 044

TSUBOI, R., 017

YANAGAWA, T., 086

Tsumaki, Noriyuki, SII-5

YASUDA, K., 050

TSUNODA, Y., 060

YASUI, M., 014

Tufail, A., 089

YAZAKI, T., 078, 079, 080

TUKAZAKI, M., SI-3

YOKOE, S., 031

U

YONEDA, M., 016

UEDA, T., 019

YOSHIDA, A., 027

UEHARA, O., 040, 052, 071

YOSHIDA, K., 040

W

YOSHIDA, T., 084

WADA, Y., 015

YOSHIMURA, K., 059, 061

WARITA, T., 030

YOSHINARI, N., 027

WASHIO, J., 051

YOTSUMOTO, K., 044

WATANABE, H., 015

YUAN, H., 042

WATANABE, K., 022

Z

WATANABE, M., 069

ZEZE, T., 045

WATANABE, N., 031

ZHANG, Y., 049

WATANABE, S., 015
WATANABE, T., 036

─ 122 ─謝

辞第 68 回国際歯科研究学会日本部会（JADR）総会・学術大会開催にあたり、下記の団体・企業様より多大なご支援を賜りました。ここに厚く御礼申し上げます。

第 68 回国際歯科研究会日本支部（JADR）総会・学術大会
大会長

石原

和幸

株式会社 池田理化株式会社 インターメディカル
サンスター 株式会社株式会社 ジーシー
株式会社 松風株式会社 吉田製作所（50 音順）─ 123 ─The 68th Annual Meeting of Japanese Association for Dental Research
Program and Abstracts of Papers

Copyright © 2020 by the 68th Annual Meeting of Japanese Association for Dental
Research. All rights reserved.
Secretary General : Department of Microbiology, Tokyo Dental College,
Tokyo Dental College Shinkan 6F
2-1-14 Misaki-cho, Chiyoda-ku, Tokyo 101-0061 JAPAN
Email: jadr68@kokuhoken.jp