Tokyo Dental College
Research Project

Asian Rising Stars Symposium 2024
July 27, 2024
Well-being Society Achieved by Maintaining and Improving
Oral-Maxillofacial Function at Every Stage of Life

（Well-being Project）

Program and Abstracts

Saturday, July 27
Tokyo Dental College Research Project
Asian Rising Stars Symposium 2024

Program
13：00-13：05：Opening Remarks
Tatsuya Ichinohe（Dean, Tokyo Dental College）
Session Ⅰ Moderator：Takehito Ouchi（Department of Physiology, Tokyo Dental College）
Tatsukuni Ohno（Oral Health Science Center, Tokyo Dental College）
13：05-13：35：Lecture Ⅰ
Calvarial stem cells：guardians of cranial bone homeostasis and injury repair
Bo Li（State Key Laboratory of Oral Diseases, National Center for Stomatology,
National Clinical Research Center for Oral Diseases, Department ofOrthodontics, West China Hospital of Stomatology, Sichuan University）
13：35-14：05：Lecture Ⅱ
PDLSC-conditioned medium reduces root resorption in delayed replantation of
avulsed teeth
Lu Jia（D epartment of Physiology, School of Basic Medicine, Emergency
Comprehensive Department, School of Stomatology, Hebei Medical
University）
Session Ⅱ Moderator：Masahide Koyachi（Department of Oral Pathobiological Science andSurgery, Tokyo Dental College）
Hitomi Sato（Department of Oral and Maxillofacial Radiology, Tokyo
Dental College）
14：05-14：35：Lecture Ⅲ
The volumetric medical image for accurate and reliable guided dentistry
Kento Odaka（Department of Oral and Maxillofacial Radiology, Tokyo Dental
College）
14：35-15：05：Lecture Ⅳ
Content evaluation of dental radiology videos on YouTube
Wai Kan Andy Yeung（Oral and Maxillofacial Radiology, Applied Oral Sciences
and Community Dental Care, Faculty of Dentistry, University of Hong Kong）

1

15：05-15：20：Coffee Break（15 min）
Session Ⅲ Moderator：Takayuki Ueda（Department of Removable Prosthodontics and Gerodontology, Tokyo Dental College）
15：20-16：00：Keynote Lecture
The importance of oral function in older adults from the viewpoint of healthy
Longevity
Masanori Iwasaki（Division of Preventive Dentistry, Department of Oral Health
Science, Graduate School of Dental Medicine, Hokkaido University）
Session Ⅳ Moderator：Mamoru Yotsuya（Department of Fixed Prosthodontics, Tokyo Dental
College）
Hideo Yonezawa（Department of Microbiology, Tokyo Dental College）
16：00-16：30：Lecture Ⅴ
A Morphological Approach to Understanding Swallowing Mechanisms～ The genioglossus muscle is the only muscle that attaches to the epiglottis. ～Kei Kitamura（Department of Histology andDevelopmental Biology, Tokyo Dental College）
16：30-17：00：Lecture Ⅵ
Inhibiting symbiotic bacterial-fungal interaction alters in vitro biofilm formationand its cariogenic potential
Jian-Na Cai（School of Oral Stomatology, Binzhou Medical University）
17：00-17：05：Closing Remarks
Akira Yamaguchi（Well-being Project advisor, Tokyo Dental College）

2

［Lecture Ⅰ］
Calvarial stem cells：guardians of cranial bone homeostasis and injury repair
Bo Li, DDS, DMD, PhD
Research Associate, Attending Physician
State Key Laboratory of Oral Diseases,
National Center for Stomatology,
National Clinical Research Center for Oral Diseases,
Department of Orthodontics, West China Hospital of Stomatology, Sichuan
University.
Abstract：
Cranial bones constitute a protective shield for the vulnerable brain tissue. Unlike long bones,
cranial bones possess unique properties in terms of developmental origin, osteogenesis progress,
and anatomical structure. The major stem cell population for cranial bone resides in the suture
mesenchyme, termed calvarial stem cells（CSCs）. However, how CSCs contribute to cranial bonehomeostasis and injury repair away from the suture remains elusive. Gli1+ cells have been identified as CSCs in vivo, and our short- and long-term lineage tracing demonstrates that Gli1+
CSCs can self-renew and display a suture-specific distribution pattern under physiological conditions. Upon calvaria injury, Gli1+ CSCs are activated and expanded, participating in injury repair and tissue regeneration by long-range migration along the dura mater. In addition, we
found that the CXCL12-CXCR4 axis plays a pivotal role in guiding Gli1+ CSC migration during
the healing process. Blocking the CXCL12-CXCR4 axis hampers injury repair and results in
non-unions, further confirmed via genetic knockout（cKO）of Cxcr4 in Gli1-lineage cells. Of note,
CXCR4 is a G protein-coupled receptor（GPCR）coupled to Gαi, which inhibits Gαs in activating
protein kinase A（PKA）. Intriguingly, mice expressing gain-of-function Gαs mutant phenocopy
Cxcr4 cKO mice with fewer Gli1+ CSCs recruited to the injury site and impaired healing. Conversely, mice expressing Gαs loss-of-function mutant exhibit accelerated bone regeneration withincreased Gli1+ CSC activation, aberrant Hedgehog signaling, and enhanced osteogenic differentiation. Dysregulated Hedgehog signaling is concomitantly amplified by injury through induced
sonic hedgehog（SHH）expression. Furthermore, anti-SHH monoclonal antibody（mAb）treatment
partially rescues the phenotype of Gαs loss-of-function mutant mice. Altogether, our data indicate that CSCs are guardians of cranial bone homeostasis and injury repair, and the CXCL12-Hedgehog signaling axis plays a critical role in regulating CSCs, shedding light on stem
cell-based therapy.

3

Curriculum Vitae
2011-2016 Undergraduate, West China School of Stomatology, Sichuan University（SCU）
2014-2014 Visiting Undergraduate, Medical Center of Hamburg University（UKE）
2015-2015 Visiting Undergraduate, Osaka Dental University（ODU）
2016-2021 Postgraduate, West China School of Stomatology, Sichuan University（SCU）
2019-2021 Visiting Postgraduate, Harvard School of Dental Medicine（HSDM）
2021-Present Research Associate/Attending Physician, West China School of Stomatology, Sichuan University（SCU）
Research Fields of Interest
1. Craniofacial Bone and Suture Biology
2. Mesenchymal Stem and Progenitor Cells
3. Cellular Senescence and Aging
4. Head and Neck Oncology
Selected Honors
1. SAKURA Exchange Program in Science, Japan Science and Technology Agency（2015）
2. Keystone Symposia Scholarship, Keystone Symposia（2020&2020）
3. Postdoctoral Fellowship Award, China Postdoctoral Science Foundation（2022）
4. Excellent Paper Award, Sichuan Stomatological Association（2023）
5. First Prize for Poster, Chinese Stomatological Association（2023）
6. International Orthodontics Foundation（IOF）Young Research Grant Award（2024）
Selected Publications
1. Li B.*, Li J., Fan Y., Zhao Z., Li L., Okano H.*, Ouchi T*. Dissecting calvarial bones and suturesat single-cell resolution. Biol Rev Camb Philos Soc. 2023；98（5）：1749-1767.（*：Co-corresponding）
2. Li B.*, Li J., Li B., Ouchi T., Li L., Li Y.*, Zhao Z*. A single-cell transcriptomic atlas characterizes age-related changes of murine cranial stem cell niches. Aging Cell. 2023；22（11）：e13980.（*：Co-corresponding）
3. Li J., Zhang Z., Tang J., Hou Z., Li L.*, Li B*. Emerging roles of nerve-bone axis in modulating
skeletal system. Med Res Rev. 2024；44（4）：1867-1903.（*：Co-corresponding）
4. Weng Z., Wang Y., Ouchi T., Liu H., Qiao X., Wu C., Zhao Z., Li L., Li B*. Mesenchymal Stem/
Stromal Cell Senescence：Hallmarks, Mechanisms, and Combating Strategies. Stem Cells
Transl Med. 2022；11（4）：356-371.（*：Corresponding）
5. Liu Y., Huang N., Qiao X., Gu Z., Wu Y., Li J., Wu C., Li B.*, Li L*. Knockdown of PGC1α suppresses dysplastic oral keratinocytes proliferation through reprogramming energy metabolism.
Int J Oral Sci. 2023；15（1）：37.（*：Co-corresponding）
6. Weng Z., Zhang B., Wu C., Yu F., Han B., Li B.*, Li L*. Therapeutic roles of mesenchymal stem
cell-derived extracellular vesicles in cancer. J Hematol Oncol. 2021；14（1）：136.（*：Co-corresponding）

4

［Lecture Ⅱ］
PDLSC-conditioned medium reduces root resorption in delayed replantationof avulsed teeth
Lu Jia, DDS
PhD student
Department of Physiology, School of Basic Medicine,
Emergency Comprehensive Department, School of Stomatology,
Hebei Medical University

Abstract：
Tooth avulsion is the most serious dental trauma, defined as the complete displacement of the
tooth from its original alveolar. Dental replantation is the standard treatment for tooth avulsion,and periodontal healing is the ideal prognosis. However, root resorption is the most common andserious complication in delayed replantation of avulsed teeth, which may lead to anterior tooth
loss in adolescents and affect aesthetics and health in physical and mental. Periodontal ligament
stem cells（PDLSC）
are considered to be the optimal cell for periodontal tissue repair and regeneration. Its conditioned medium can be used for cell-free therapy, which is convenient to obtain,
fully utilizes bioactive factors, and avoids immune rejection and ethical concerns associated withstem cell transplantation. In this study, we collected clinical specimens and found high expression of osteoclast related factors and inflammatory factors in the periapical soft tissue of delayed
replantation tooth. PDLSC-CM significantly promoted the healing of the periodontal ligament, reduced root resorption and inflammatory reactions in rats received delayed dental replantation.
Moreover, PDLSC-CM inhibited the osteoclast formation and reduced M1 polarization in osteoclast precursors and Raw264.7 macrophages. In addition, proteomics data revealed that HAPLN1
was markedly downregulated in PDLSC-CM treated replantation roots, and overexpression of
HAPLN1 cancelled the protective effect of PDLSC-CM on root resorption. In summary, ourstudy uncovers that PDLSC-CM promotes periodontal ligament healing and reduces root resorption by downregulating HAPLN1 in delayed replantation of avulsed teeth. PDLSC-CM can beused as preservation medium for avulsed teeth, which is expected to be widely applied in clinical practice.

5

Curriculum Vitae
2013-2018 Bachelor
2018-2021 Master2021-2022 Dentist
2022-Present PhD candidate

School of Stomatology, Hebei Medical University
School of Stomatology, Nanjing Medical University
Stomatological Hospital of Hebei Medical University
School of Basic Medicine, Hebei Medical University

Research Fields of Interest
1. The application of stem cells in oral diseases
2. The regulation of the nervous/vascular system in bone and dental metabolism
Selected Publications
1. Jia L.#, Yang Z.#, Sun L.#, Zhang Q., Guo Y., Chen Y., Dai Y., & Xia Y.（2021）. A three-dimensional-printed SPION/PLGA scaffold for enhanced palate-bone regeneration and concurrent alteration of the oral microbiota in rats. Materials science & engineering. C, Materials for biological applications, 126, 112173. https：//doi.org/10.1016/j.msec.2021.112173
2. Shi Z., Jia L., Zhang Q., Sun L., Wang X., Qin X., & Xia Y.（2022）. An altered oral microbiota
induced by injections of superparamagnetic iron oxide nanoparticle-labeled periodontal ligament stem cells helps periodontal bone regeneration in rats. Bioengineering & translational
medicine, 8（3）,e10466. https：//doi.org/10.1002/btm2.10466
3. Han L.#, Guo Y.#, Jia L.#, Zhang Q., Sun L., Yang Z., Dai Y., Lou Z., & Xia Y.（2021）.3D magnetic nanocomposite scaffolds enhanced the osteogenic capacities of rat bone mesenchymal stem
cells in vitro and in a rat calvarial bone defect model by promoting cell adhesion. Journal ofbiomedical materials research. Part A, 109（9）, 1670-1680. https：//doi.org/10.1002/jbm.
a.37162
4. Xia Y., Zhao Y., Zhang F., Chen B., Hu X., Weir M. D., Schneider A., Jia L., Gu N., & Xu H. H.
K.（2019）. Iron oxide nanoparticles in liquid or powder form enhanced osteogenesis via stem
cells on injectable calcium phosphate scaffold. Nanomedicine：nanotechnology, biology, andmedicine, 21, 102069. https：//doi.org/10.1016/j.nano.2019.102069
5. Guo X., Ma H., Cui Z., Zhao Q., Zhang Y., Jia L., Zhang L., Guo H., Zhang X., Zhang Y., Guan Y.,& Ma H.（2024）. Chronic Intermittent Hypobaric Hypoxia Reduces Hypothalamic N-Methyl-d-Aspartate Receptor Activity and Sympathetic Outflow in Spontaneously Hypertensive
Rats. High altitude medicine & biology, 25（1）,77-88. https：//doi.org/10.1089/ham.2023.0098

6

［Lecture Ⅲ］
The volumetric medical image for accurate and reliable guided dentistry
Kento Odaka, DDS, PhD
Senior Assistant Professor
Department of Oral and Maxillofacial Radiology, Tokyo Dental College

Abstract：
Imaging modalities such as CT and MRI are commonly employed in the oral and maxillofacial
field for diagnostic and treatment planning purposes. These modalities can provide both qualitative and quantitative data, including information on the boundary and content of lesions, as well
as volumetric data on the morphology of the patient's anatomical structures. The main theme of
my research is to improve the precision and reliability of guided diagnosis and dental treatment
through an interdisciplinary approach. This entails extracting any area from the data obtained,reconstructing it in three dimensions and using it as a basis for computer-aided design（CAD）foradditive manufacturing（AM）,extended reality（XR）and radiomics.
AM is the fabrication technique for a three-dimensional object from a CAD model with the material being added layer by layer. In our projects, the additive manufactured devices were used
to physically guide the manipulation of the instruments in surgery and endodontic treatment as
designed before the treatment. Furthermore, we have assessed the directly fabricated prostheses such as denture bases or clasps by AM with the aim of optimal designing for individual patients before manufacturing. XR is an umbrella term to refer to augmented reality（AR）, virtual
reality（VR）,and mixed reality（MR）.The advent of XR technology has enabled the realisation ofsimultaneous bidirectional communication including visual information, with the potential to revolutionise the field of education, clinical conferencing, and real-time guided surgery. Radiomics isa method that extracts a vast array of features from medical images through the utilisation ofdata-characterisation algorithms. Deep learning technology has a profound affinity with image
recognition, including medical images, and is expected invaluable in the field of segmentationand diagnosis, with an understanding of its limitations.
In this presentation, I will showcase our work in the domains of oral and maxillofacial surgery,endodontics, and prosthodontics.

7

Curriculum Vitae
2012 DDS, Tokyo Dental College, Tokyo, Japan2017 PhD, Graduate School of Dentistry, Tokyo Dental College, Tokyo, Japan2017-2018 Assistant Professor, Department of Anatomy, Tokyo Dental College, Tokyo, Japan
2018-2021 Assistant Professor, Department of Oral and Maxillofacial Radiology, Tokyo Dental
College, Tokyo, Japan2021-Present Senior Assistant Professor, Department of Oral and Maxillofacial Radiology, Tokyo Dental College, Tokyo, Japan2023-2024 Visiting Researcher, Department of Oral and Maxillofacial Surgery, Charité-Universitätsmedizin Berlin, Berlin, Germany
Research Fields of Interest
Image Segmentation, CAD, Additive Manufacturing, Biomechanics, Radiomics
Selected Publications
1. Odaka K., Steffen C., Wagendorf O., Geißler S., Ebker T., Rubarth K., Nguyen T.T., Bortel E.L.,
Sarasaen C., Duda G.N., Heiland M., Voß J.O. Volumetric Evaluation of Osteotomy Gap Following Mandibular Bilateral Sagittal Split Osteotomy Using a Novel Semi-Automated Approach：A Pilot Study. Clinical Oral Investigations 28：358, 2024
2. Koyachi M., Sugahara K., Tachizawa K., Nishiyama A., Odaka K., Matsunaga S., Sugimoto M.,
Tachiki C., Nishii Y., Katakura A. Enhanced Precision in Genioplasty：A Novel Intraoperative
Spatial Repositioning Using Computer-Aided Design and Manufacturing Technology and a Holographic Mixed Reality Application. Journal of Clinical Medicine 12（23）7408, 2023
3. Noguchi T., Odaka K., Fukuda K. Clinical Application of Inferior Alveolar Nerve Block Device
for Safe and Secure IANB by Any Operator. Pain Research and Management 2023：1-7,
2023
4. Odaka K., Kamiyama S., Takizawa H., Takano N., Matsunaga S. Comparison of the fatigue lifeof pure titanium and titanium alloy clasps manufactured by laser powder bed fusion and its
prediction before manufacturing. Journal of Prosthodontic Research 67（4）：626-32, 2023
5. Yamada M., Odaka K., Kasahara N., Matsunaga S., Tamiya Y., Sako R., Furusawa M. A Caseof Non-surgical Root Canal Treatment Using an Operating Microscope on Type Ⅲ-b Dens Invaginatus. Operative Dentistry, Endodontology and Periodontology 1（1）：97-104, 2021

8

［Lecture IV］
Content evaluation of dental radiology videos on YouTube
Wai Kan Andy YEUNG, BDS, PhD
Tutor in Radiography
Oral and Maxillofacial Radiology,
Applied Oral Sciences and Community Dental Care,
Faculty of Dentistry, University of Hong Kong

Abstract：
In this era of digital learning, dental students, clinicians, and patients often seek online information on health topics, including dental health. YouTube is a very popular online platform thathosts many free-to-watch, user-generated videos. Many videos related to dental radiology areavailable on YouTube, but the quality of their contents was not thoroughly evaluated before. A
series of YouTube video evaluations were performed with the following foci：instructional videos that demonstrated the procedures to take periapical and panoramic radiography, videos that
explained the radiographic anatomy on panoramic images, and videos that discussed radiation
safety concerning dental radiology. Overall, the videos were informative and useful, but with thefollowing areas for improvement. For videos on how to take periapicals, common issues included
not removing the metallic objects from the patient’s head and neck region, not showing the selection of radiation dose, and not placing the orientation dot on the film or phosphor plate on theocclusal side. For videos on how to take panoramics, none of them clearly showed that the operator was pressing the exposure button outside the radiographic room with its door closed, as
most of them either showed an open door, with no door, or without enough information. For
panoramic radiographic anatomy videos, each video described 26 landmarks on average. The
maxillary sinus was the structure mostly involved in wrong information, particularly the wrong
delineation of its posterior wall. For videos on radiation safety, some of the analogies and theclaimed radiation dose were questionable. One video even wrongly stated that dental x-rays arenonionizing radiation.

9

Curriculum Vitae
2012 BDS, HKU Dentistry2017 PhD, HKU Dentistry2015-present Tutor in Radiography, HKU Dentistry2020-present C linic Manager, Oral Diagnosis Clinic and Diagnostic Imaging, Prince Philip Dental Hospital（associated with HKU Dentistry）
Award
2017 Outstanding Research Postgraduate Student（2016-2017）,HKU
Selected publications
1. Yeung A. W. K.*, Parvanov E. D., Horbańczuk J. O., Kletecka-Pulker M., Kimberger O.,
Willschke H., & Atanasov A. G.（2023）.Are dental x-rays safe? Content analysis of English andChinese YouTube videos. Digital Health, 9, 20552076231179053.
2. Wong N. S. M., Yeung A. W. K., McGrath C. P., & Leung Y. Y.（2023）. Qualitative Evaluationof YouTube Videos on Dental Fear, Anxiety and Phobia. International Journal of Environmental Research and Public Health, 20, 750.
3. Grillon M., & Yeung A. W. K.*（2022）.Content Analysis of YouTube Videos That Demonstrate
Periapical Radiography. Applied Sciences, 12, 9602.
4. Yeung A. W. K.*（2022）.Content analysis of YouTube videos on radiographic anatomy on dental panoramic images. Healthcare, 10, 1382.
5. Grillon M., & Yeung A. W. K.*（2022）. Content analysis of YouTube videos that demonstrate
panoramic radiography. Healthcare, 10, 1093.

10

［Keynote Lecture］
The importance of oral function in older adults from the viewpoint of healthy
longevity
Masanori Iwasaki, DDS, PhD
Professor
Division of Preventive Dentistry, Department of Oral Health Science,
Graduate School of Dental Medicine, Hokkaido University

Abstract：
Although older adults retain their teeth for longer, they report complaints concerning oral function. The oral health treatment needs of the older population have changed. In addition to methods focused on the teeth affected by dental caries and periodontal diseases, methods focused on
the adequate functioning of oral cavity are now needed. Because individual oral health problems
are interrelated and their prevalence increases with age, older adults frequently have coexistingoral health problems. Therefore, poor oral function-related problems are becoming more common as society ages. As further attention is given to the importance of oral function in aging
populations, new concepts referred to as oral frailty and oral hypofunction have been introduced
as multidimensional concepts describing poor oral function in Japan. In particular, the "Joint
Working Committee on Oral Frailty" by three academic societies：the Japan Geriatrics Society,
the Japanese Society of Gerodontology, and the Japanese Association on Sarcopenia and Frailty,
issues Consensus Statement on Oral Frailty, on April 1st, 2024, with the aim to further public understanding of oral frailty.
In the ARSS 2024, I aim to provide an overview of recent epidemiological evidence of the associations of poor oral function with dietary intake and general health from the perspective of oral
frailty and oral hypofunction. Oral frailty and oral hypofunction are novel concepts. Maintaining
good oral function may be key to healthy longevity.

11Curriculum Vitae
2023-Present Professor, Division of Preventive Dentistry, Department of Oral Health Science,
Graduate School of Dental Medicine, Hokkaido University2023-Present Visiting Researcher, Tokyo Metropolitan Institute for Gerontology and Geriatrics
2022-2023 Vice Research Director, Tokyo Metropolitan Institute for Gerontology and Geriatrics
2020-Present：Visiting Professor, Kyushu Dental University
2020-2022 Vice Specialized Director, Tokyo Metropolitan Institute for Gerontology and Geriatrics
2014-2020 Associate Professor, Kyushu Dental University
2010-2014 Assistant Professor, Graduate School of Medical and Dental Sciences, Niigata University
2010：Clinical Fellow, Graduate School of Medical and Dental Sciences, Niigata University
2009-2010 Visiting Scholar, University of Michigan
2007-2010 Ph.D. of Dental Medicine, Graduate School of Medical and Dental Sciences, Niigata
University
2006 Residency, Niigata University Medical & Dental Hospital
2000-2006 B.A. of Dental Medicine, School of Dental Medicine, Hokkaido University
Awards2023 Geriatrics & Gerontology International Best Reviewer Award
2019 LION Award, Japanese Society of Gerodontology
2018 LION Award, Japanese Society for Oral Health2012 Best Paper Award, Japanese Society for Oral Health2010 JADR Young Investigator Award
Selected Publications
1. Iwasaki M., et al. Prevalence of oral frailty and its association with dietary variety, social engagement, and physical frailty：Results from the Oral Frailty 5-item Checklist. Geriatrics &Gerontology International. 2024. 24（4）：371-377.
2. NCD Risk Factor Collaboration. Diminishing benefits of urban living for children and adolescents’growth and development. Nature. 2023. 615：874-883.
3. Iwasaki M., et al. Decline in oral function and its management. International Dental Journal.
2022. 72（4S）：S12-S20.
4. Iwasaki M., et al. The association of oral function with dietary intake and nutritional statusamong older adults：latest evidence from epidemiological studies. Japanese Dental Science
Review. 2021. 57：128-137.
5. Iwasaki M., et al. Serum antibody to porphyromonas gingivalis in chronic kidney disease. Journal of Dental Research. 2012. 91（9）：828-833.

12

［Lecture Ⅴ］
A Morphological Approach to Understanding Swallowing Mechanisms～ The genioglossus muscle is the only muscle that attaches to the epiglottis. ～Kei Kitamura, DDS, PhD
Senior Assistant Professor
Department of Histology and Developmental Biology, Tokyo Dental College

Abstract：
Epiglottic retroversion is difficult to explain anatomically. One reason is inadequate structural
identification of the ligaments in the submucosal tissue anterior to the epiglottis（pre-epiglottic
space, PES）
. Although studies have shown that tongue root movement plays a role in epiglottic
retroversion, few morphological reports have investigated the attachment of the lingual muscles
to the epiglottis. This study reconstructed the fiber structure of the PES by comprehensively
analyzing fiber alignment in the PES focusing on the hyoepiglottic ligament, which runs between the lingual muscles and the epiglottis. Gross and microscopic observations of the submucosal structures from the tongue to the larynx of 20 cadavers（10 men, 10 women； mean age 79
years）were performed. A tendon continuing from the posterior part of the genioglossus muscle
and attaching to the center of the epiglottic cartilage was identified in the midline area of theepiglottis. We named this tendon the glossoepiglottic tendon. In contrast, the hyoepiglottic ligament is found between the hyoid bone and the epiglottis and is attached from the lateral marginof the epiglottic cartilage to its base. Furthermore, the glossoepiglottic tendon consists of ahigh-density fiber bundle that is thicker than the hyoepiglottic ligament. These results showthat the conventional hyoepiglottic ligament has a two-layer structure consisting of an upper fiber bundle connected to the genioglossus muscle and a lower fiber bundle connected to the hyoidbone. Sustained contraction of the posterior part of the genioglossus muscle therefore places theepiglottis under persistent traction, suggesting that its relaxation may cause epiglottic retroversion.

13

Curriculum Vitae
2012 DDS, Tokyo Dental College, Japan
2016 PhD, Department of Anatomy, Tokyo Dental College, Japan
2016-2017 Research assistant, Department of Histology and Developmental Biology, Tokyo Dental College, Japan2017-2021 A ssistant Professor, Department of Histology and Developmental Biology,
Tokyo Dental College, Japan2021-2024 Senior Assistant Professor, Department of Histology and Developmental Biology, Tokyo Dental College, Japan
Honor
2019 The Japanese Society of Dysphagia Rehabilitation“encouragement award”
Research Fields of Interest
Human Histology, Human embryology, Lingual muscle, Dysphagia, Age-related change in oralsoft tissues
Selected Publications
1. Kitamura K., Suzuki R., Ishizuka S., Murakami G., odríguez-Vázquez JF., Yamamoto H., Abe S.
Growing stylohyoideus muscle insertion to the hyoid bone with special reference to Its topographical relation to the intermediate tendon of digastricus muscle：a histological study using
human fetuses. Ann Anat（in press）, 2024.
2. Kitamura K., Ishizuka S., Ji Hyun Kim., Yamamoto H., Murakami G., Rodríguez-Vázquez JF.,
Abe S. Development and growth of the temporal fascia：a histological study using human fetuses. Anat Cell Biol（in press）, 2024.
3. Kitamura K., Watanabe T., Yamamoto M., Ishikawa N., Kasahara N., Abe S., Yamamoto H. A
Newly Discovered Tendon Between the Genioglossus Muscle and Epiglottic Cartilage Identified by Histological Observation of the Pre-Epiglottic Space. Dysphagia, 38（1）：315-329, 2023.
4. Kitamura K., Kim JH., Cho KH., Murakami G., Rodríguez-Vázquez JF., Yamamoto H. Regional
differences in zygapophysial joint cavities：A histological study of human fetuses. Anat Rec（Hoboken）,304（5）：979-990, 2021.

14

［Lecture Ⅵ］
Inhibiting symbiotic bacterial-fungal interaction alters in vitro biofilm formation and its cariogenic potential
Jian-Na Cai, PhD
LectureSchool of Oral Stomatology, Binzhou Medical University

Abstract：
The emergent property of polymicrobial biofilm is a consequence of intricate microbial interaction that occurs in response to individual cells interactions. Association between Streptococcus
mutans and Candida albicans is resulted in a mutually beneficial cross-kingdom cluster, which is
structurally complex and displaying enhanced cariogenic potential of biofilm. Given the polymicrobial niche in the oral cavity, both S. mutans and C. albicans are competitive with intrinsic
and extrinsic microbes. Here, we hypothesized that applying antagonistic interaction of extrinsic
lactic acid bacteria including Lacticaseibacillus rhamnosus towards S. mutans and C. albicans isa feasible strategy to disrupt the virulent cross-kingdom biofilm. Furthermore, combination ofcollagen peptide（CP）with L. rhamnosus can synergistically inhibit bacterial-fungal biofilm formation and further inhibit its cariogenic properties. Using a dynamic microbial-interaction model,
the results showed that L. rhamnosus significantly impaired a dense and complex cariogenic biofilm formation. Although single treatment of CP cannot inhibit the growth of bacterial or bacterial-fungal mixed-species biofilms, it significantly decreased glycolytic acid production of bacterial-bacterial or bacterial-fungal biofilms when co-cultured with L. rhamnosus. Mechanically, L.
rhamnosus modulated the virulence potential of this cross-kingdom biofilm via down-regulationof the genes associated with bacterial-fungal interaction, biofilm formation and yeast-to-hyphaetransition. Interestingly, in KEGG analysis, combination of L. rhamnosus with CP altered membrane functions of both S. mutans and C. albicans without affecting the membrane/cellular functions of L. rhamnosus, akin to the mechanism of action of F-ATPase inhibitors. The data provide
new insights for therapeutic strategies targeting microbial interaction in cross-kingdom biofilms
via enhancement of the antagonistic effect of probiotics towards virulent cross-kingdom oral biofilm.

15

Curriculum Vitae
2008-2013 Bachelor
2013-2015 Master2015-2018 PhD
2021-2023 Postdoc
2018-Present Lecture

Binzhou Medical University
Jeonbuk National University
Jeonbuk National University
Jeonbuk National University
Binzhou Medical University

Research Fields of Interest
1. Dental biofilms
2. Microbial ecology in the oral cavity
3. Therapeutic approaches targeting cariogenic biofilms
Selected Publications
1. Cai JN., Kim D. Biofilm ecology associated with dental caries：understanding of microbial interactions in oral communities leads to development of therapeutic strategies targeting cariogenic biofilms. Adv Appl Microbiol. 2023；122：27-75.
2. Cai JN., Choi HM., Song KY., Jeon JG. The reciprocal interaction between fluoride release ofglass ionomers and acid production of Streptococcus mutans biofilm. J Oral Microbiol. 2022；
14（1）：2055267.
3. Cai JN., Choi HM., Jeon JG. Relationship between sucrose concentration and bacteria proportion in a multispecies biofilm. J Oral Microbiol. 2021；13（1）：1910443.
4. Cai JN., Jung JE., Lee MH., Choi HM., Jeon JG. Sucrose challenges to Streptococcus mutans biofilms and the curve fitting for the biofilm changes. FEMS Microbiol Ecol. 2018；94（7）：fiy091.
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