bluuebunny/crossref_metadata_2025 huggingface dataset:
A survey on working length determination of endodontic treatment
Authors: Ahn Hye-ra , Seo Min-Seock
Published: August 2024

The purpose of this study is to evaluate the preferred method of root canal length determination and the apical limit for canal instrumentation among endodontic teachers of dental school. A questionnaire on the preferred method of root canal length determination and the apical limit for canal instrumentation was designed and distributed to endodontic teachers of various dental schools. The response rate was 90%. The most preferred method of root canal length determination was Electronic apex locator (EAL)(89%). The most favoured apical limit for canal instrumentation was 0.5 to 1.0 mm short of the radiographic apex(78%). The most preferred method of using EAL was that the working length is taken at 'APEX' mark and then distracted 0.5mm from that length.(41%). When there is no agreement between radiographic measurement and EAL measurement, 74% of respondents chose the length of EAL measurement. The majority of endodontic teachers from Korean dental schools preferred EAL to radiograph method in determining root canal length.
Maintenance of complete denture
Authors: Song Young-Gyun
Published: August 2024

As residual ridge resorption occurs, complete dentures tend to become loose. Denture relining and rebasing are an essential element for improving a denture's stability and prevention side effect such as sore spot, epulis fissuratum. This paper focuses about health insurance is available for maintenance of complete denture and, methods of relining or rebasing.
Efficiency of the nickel-titanium rotary instruments for glide path preparation: in-vitro preliminary study
Authors: Kim Hyeon-Cheol , Kwak Sang Won , Ha Jung-Hong
Published: August 2024

Objectives: This preliminary study compared the effects of glide path establishing instruments prior to substantial root canal preparation. Materials and Methods: Glide path was established by enlargement of the 2nd mesiobuccal root canal of Dentalike by using three kinds of glide path preparation nickel-titanium file; PathFile, One G and ProGlider. The pre- and post-instrumented Dentalikes were weighed in the resolution of 1 / 10mg. In addition, after glide path preparation, torque generated during shaping using the WavoOne file was measured. The data were analyzed by one-way ANOVA and Tukey post-hoc test at a significance level of 95%. Results: The ProGlider had the significantly larger amount of reduced weight than other instrument groups (p < 0.05). There was no significant difference between group of glide path preparation with ProGlider and without glide path preparation in maximum torque and total stress generation during the shaping with WaveOne. Conclusions: Glide path preparation instruments may have different efficiency according to their geometries. The Dentalike artificial teeth were revealed to have discrepancies in the size of root canals by microCT examination. It is impossible to make a meaningful judgment of the results due to the reliability or resolution problem of the root canal size of the artificial tooth selected as the standardized tooth.
Comparative inorganic analysis of the mesiodens and the 3rd molar as the autogenous tooth graft materials
Authors: Lee Sung-Suk , Kim Su-Gwan , Oh Ji-Su , You Jae-Seek , Kim Won-Gi , Yang Jung-Eun , Lim Hyoung-Sup
Published: August 2024

Objective: The aim is to evaluate the potential of the mesiodens through the comparative inorganic analysis of 3rd molar teeth prior to clinical study. Material and methods: The extracted mesiodens and the 3rd molar teeth were prepared. The teeth are prepared as in the process of the autogenous tooth bone graft. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) analysis was performed for inorganic analysis. Results: Rough and porous surfaces were observed in all materials in SEM analysis. Ca/P ratio of mesiodens was 1.55 and the 3rd molar was 1.22 in EDS analysis. XRD analysis shows that the 3 main peaks position were similar. This means that the graft materials are very similar to that of the crystallinity. Conclusions: The mesiodens and the 3rd molar teeth are very similar to the inorganic component. These results provide the reasonable rationale that mesiodens can be used as autogenous tooth bone graft in a clinic.
Application of the QLF technology to monitor recovery rates of enamel caries lesions with human saliva
Authors: Kim Gyung-Min , Ku Hye-Min , Lee Eun-Song , Kang Si-Mook , Jong Elbert de Josselin de , Kwon Ho-Keun , Kim Baek-Il
Published: August 2024

Purpose: The aim of this in vitro study was to assess changes in remineralization by stimulated human saliva over a short period of 48 hours with quantitative light-induced fluorescence (QLF) technology. Materials and Methods: Bovine incisor surfaces were demineralized for 10 days. Two types of stimulated saliva were collected from 7 healthy persons. 24 hours after tooth brushing (Stimulated saliva group) and immediately after tooth brushing with 1,000 ppm NaF dentifrice (Dentifrice saliva group). The specimens were immersed in saliva and fluorescence images were obtained by QLF-digital (QLF-D biluminatorTM,) at 2, 4, 6, 12, 24, and 48 hours fluorescence loss (DeltaF%) of the lesions. A paired t-test was performed to assess fluorescence differences between before (DeltaF_baseline) and after (DeltaF_treatment;time) the remineralization process. Results: Before the remineralization, the mean DeltaF_baseline of the initial demineralized specimens was -18.42pm0.15 (%). In both groups, the DeltaF values obtained at baseline and after 2 hours were statistically significant (P < 0.001), indicating recovery of the lesions by approximately 40% after 2 hours. After 48 hours, remineralization rates were slightly higher (49%) for the stimulated saliva group than for the dentifrice saliva group (41%), but the difference was not statistically significant. Conclusions: With QLF minute degrees of remineralization by saliva can be measured in periods as short as 2 hours. Additionally no significantly higher effects of remineralization were observed in the dentifrice saliva group when compared to the stimulated saliva group.
Clinical application method and the meaning of interdental brush
Authors: Cho Hyun-Jae
Published: August 2024

Periodontitis is the major concern of oral disease to human, and begins in the interdental area. The aim of this study is to discuss the clinical application method and the meaning of interdental brush. It is very difficult to change oral health behaviors, because patients believe that it is enough that the reason of tooth brushing is to remove food debris, not dental biofilm. Moreover, there are several barriers for using interdental brush. For the better oral health and maintenance of dental prosthesis, it is very important to motivate the use of the interdental brush well, and teach the desirable design of the interdental brush and the clinical meaning to patients.
Evaluation of antral exostoses in a Korean population
Authors: Cho Bong-Hae , Jung Yun-Hoa
Published: August 2024

Purpose: This study was performed to survey the incidence and imaging characteristics of the antral exostoses in a Korean population. Materials and methods: The cone-beam computed tomographic images of 5,268 patients were reviewed for the presence of antral exostoses. Incidence, location, shape, structure and dimension were evaluated. Gender and side difference were analyzed by chi-squared test. Results: Ninety eight antral exostoses were found in 78 (1.5%) out of 5,268 patients. Gender and sides showed no statistically significant differences. Antral exostoses was often found in the lateral wall and floor of the maxillary sinus, accounting for 58.2% and 38.8% of the exostoses, respectively. Most exostoses had broad base and were composed of spongy bone surrounded by compact bone. The mean dimension was 9.1(W)*4.9(D)*5.3(H) mm. Conclusion: Antral exostoses is not uncommon in a Korean population. The identification of antral exostoses is clinically significant to avoid unnecessary examination and treatment. It also needs to be examined carefully in the implant planning or sinus lift procedure.
Surgery-First Orthodontic Approach for the patients
Authors: Kook Minsuk
Published: August 2024

The traditional orthognathic surgery treatment consists of three steps: preoperative orthodontic treatment, orthognathic surgery, and postoperative orthodontic treatment, and the average treatment period is usually two years. Also, patients with Class III malocclusion should spend more time getting their facial features worse during the decompensation process. However, most of the patients who want orthognathic surgery visit the chief complaints of appearance improvement, and resolve this address as soon as possible. The concept of °AESurgery - First 'does not cause a facial imbalance caused by decompensation for the pre - operative correction period, and the patient can obtain an improved facial profile immediately after the operation. In addition, the correction period is shortened by Regional Acceleratory Phenomenon (RAP) after surgery. However, it is not applicable to all patients. Patients with severe crowding, severe curve of spee or reverse curve of spee, severe transverse discrepancy of the maxilla and mandibular arch, and severe incisal angles are less likely to apply the technique. Although it is not yet possible to apply this technique to all patients, it has many advantages over the conventional method. Especially, the patients' preference is increasing due to the rapid appearance improvement and the shortening of the total treatment period.
Tooth dentin regeneration and its clinical application
Authors: Bae Hyun Sook , Park Joo-Cheol
Published: August 2024

Teeth are made up of three hard tissues, enamel, dentin, and cementum. The dental pulp is the only non-mineralized connective tooth tissue that is surrounded by dentin. The dentin-pulp complex is able to respond to injury by producing hard tissue deposition. However, dentin is considered one of the most difficult tissues to regenerate because of its unique anatomic and physiologic nature. Recently, advances in understanding the applicability of bio-active dentin regenerating proteins are emerging with the development of biological-based therapies using bio-active materials. Dentin defects were regenerated by the deposition of tubular physiologic dentin after application of the bio-active protein in a beagle dog model. Therefore, the bio-active protein may be able to serve as a novel dentin regenerating material and improve symptoms of dentin hypersensitivity.
Clinical anatomic consideration of the superficial layer of the masseter muscle for botulinum toxin injection
Authors: Lee Hyung-Jin , Kim Hee-Jin
Published: August 2024

In clinical dentistry, botulinum toxin is generally used to treat the square jaw, bruxism, and temporomandibular joint diseases. Recently, this procedure has been expanded and applied for cosmetic purposes, and it is becoming a key task to be aware of the precise anatomical structure of the target muscles to be cautious during treatment and how to prevent side effects. Therefore, the purpose of this study is to observe the anatomical structure of the superficial layer of masseter muscle and to provide a most effective botulinum toxin injection method through clinical anatomical consideration. It was observed that the muscle belly of superficial part of the superficial layer was originated from the deep to the aponeurosis of masseter muscle and descend, then changed gradually into the tendon structure attaching to the inferior border of the mandible. In this study, we named this structure deep inferior tendon. This structure was observed in all specimens. We conclude that the use of superficial layer and deep layer injection should be considered to prevent paradoxical masseteric bulging in consideration of the deep inferior tendon of superficial part of superficial layer of masseter muscle.
Multidisciplinary treatment of generalized aggressive periodontitis: case report
Authors: Cha Hyun-Jeong , Bae Ju-Eun , Cho Jin-Hyun , Suh Jo-Young
Published: August 2024

Generalized aggressive periodontitis cause intrabony pocket, loss of teeth, and severe alveolar bone defect. As a result, pathologic tooth migration occurs and esthetic problem happens according to this, especially on the anterior teeth of maxilla. The purpose of this study was to assess the multidisciplinary treatment including periodontics, orthodontics and prosthetics of a patient caused by generalized aggressive periodontitis. This study presents a case using full mouth periodontal treatment, immediate orthodontic treatment for 5 months, implantation with guided bone regeneration and free gingival graft, and prosthetic treatment. Treatments took totally 14 months. Periodontal indicators such as probing pocket depth, bleeding on probing, tooth mobility improved. Also, the patient was satisfied with the esthetic and functional improvement.
The incidence of odontogenic tumors and clinical and radiological reviews for the most frequent three types in Korea
Authors: Kim Do Kyeong , Kim Jin
Published: August 2024

The aim of this study is to examine the incidence of odontogenic tumors and to review the clinical and radiological findings for the most frequent three types in Korea. Odontoma, ameloblastoma and keratocystic odontogenic tumors are the most frequent odontogenic tumors in Korea. We provide an overview of these tumors based on clinical and radiographic findings.
Outlier detection in dental research
Authors: Kim Ki-Yeol
Published: August 2024

In clinical dental research, errors occur in spite of careful study design and conduct. Data cleaning procedures intend to identify and correct these errors or at least to minimize their influence on study. Outlier is the one of these errors. Outlier detection is the first step in data analysis process which has a serious effect in the field of dental research. Hence, this paper aims to introduce the methods to detect the outliers and to examine their influences in statistical data analysis.
Efficacy and safety of 2% lidocaine HCl with 1:200,000 epinephrine
Authors: Karm Myong-Hwan
Published: August 2024

INTRODUCTION The most commonly impacted tooth is the third molar. An impacted third molar can ultimately cause acute pain, infection, tumors, cysts, caries, periodontal disease, and loss of adjacent teeth. Local anesthesia is employed for removing the third molar. This study aimed to evaluate the efficacy and safety of 2% lidocaine with 1:80,000 or 1:200,000 epinephrine for surgical extraction of bilateral impacted mandibular third molars. METHODS Sixty-five healthy participants underwent surgical extraction of bilateral impacted mandibular third molars in two separate visits while under local anesthesia with 2% lidocaine with different epinephrine concentration (1:80,000 or 1:200,000) in a double-blind, randomized, crossover trial. Visual analogue scale pain scores obtained immediately after surgical extraction were primarily evaluated for the two groups receiving different epinephrine concentrations. Visual analogue scale pain scores obtained 2, 4, and 6 h after administering an anesthetic, onset and duration of analgesia, onset of pain, intraoperative bleeding, operator's and participant's overall satisfaction, drug dosage, and hemodynamic parameters were evaluated for the two groups. RESULTS There were no statistically significant differences between the two groups in any measurements except hemodynamic factors (P > .05). Changes in systolic blood pressure and heart rate following anesthetic administration were significantly greater in the group receiving 1:80,000 epinephrine than in that receiving 1:200,000 epinephrine (Pleq01). CONCLUSION The difference in epinephrine concentration between 1:80,000 and 1:200,000 in 2% lidocaine liquid does not affect the medical efficacy of the anesthetic. Furthermore, 2% lidocaine with 1:200,000 epinephrine has better safety with regard to hemodynamic parameters than 2% lidocaine with 1:80,000 epinephrine. Therefore, we suggest using 2% lidocaine with 1:200,000 epinephrine rather than 2% lidocaine with 1:80,000 epinephrine for surgical extraction of impacted mandibular third molars in hemodynamically unstable patients.
Devices for reducing Pain during local anesthesia
Authors: Park Wonse
Published: August 2024

Dental local anesthesia is important procedure for the elimination of pain during dental treatment. However, the pain during local anesthesia is one of the main source of fear to the patients. The cause of pain during dental local anesthesia includes soft tissue damage during penetration of the oral mucosa, pressure from the spread of the anesthetic solution, temperature of anesthetic solution, low pH of anesthetic solution, and the characteristics of the drug. Several concepts and devices introduced to date to reduce the pain during local anesthesia for dental treatment. In this report, devices that can reduce the pain during local anesthesia will be discussed.
Digital impression taking for full-arch implant restoration to a patient with microstomia
Authors: Shim Ji Suk , Ryu Jae Jun
Published: August 2024

This clinical case highlights the failure of long length implants, and the prosthodontic procedures necessary to rehabilitate the maxillary dentition of a patient with microstomia. The integrated digital technology of intra-oral scanning, computer-aided design, and three-dimensional printing can provide an alternative method to make conventional impressions for patients with microstomia who cannot insert the appropriate tray in their mouths.
Combined effects of a chemically cross-linked porcine collagen membrane and highly soluble biphasic calcium phosphate on localized bone regeneration
Authors: Kim You-Kyoung , An Yin-Zhe , Cha Jae-Kook , Lee Jung-Seok , Jung Ui-Won , Choi Seong-Ho
Published: August 2024

Objectives: Aim of this study was to evaluate bone regenerative efficacy of a chemically cross-linked porcine collagen membrane (CM) when used in combination with highly soluble biphasic calcium phosphate (BCP). Materials and methods: Physiochemical properties of the experimental collagen membrane were analyzed. Four circumferential defects with diameter of 8 mm were created in each calvarium of New Zealand white rabbits (n = 10). Defects were randomly allocated to one of following 4 groups: 1) BCP-CM (BCP (20% hydroxyapatite/80% beta-tricalcium phosphate) covered with the prepared collagen membrane), 2) BCP (only BCP used), 3) CM (only the prepared collagen membrane used), and 4) C (control; only blood clot). After 2 weeks (n = 5) and 8 weeks (n = 5), histologic and histomorphometric analyses were performed. Results: The experimental collagen membrane exhibited dense and compact structure, relatively high tensile strength and lower degradability. Histologic analyses revealed that new bone increased rapidly at 2 weeks, while defect was preserved at 8 weeks. Histomorphometric analyses revealed that the new bone areas increased in the BCP-grafted groups over 8 weeks, with BCP-CM exhibiting greater total augmented area than that of BCP group both at 2 weeks (27.12pm3.99 versus 21.97pm2.27mm2) and 8 weeks (25.75pm1.82 versus 22.48pm1.10mm2) (P < 0.05). Conclusions: The experimental collagen membrane successfully preserved localized defect for 8 weeks despite early rapid resorption of BCP. Within the study limitations, combined use of the chemically cross-linked porcine collagen membrane and highly soluble BCP aided localized bone regeneration.
A study on Radix Entomolaris about prevalence and correlation of canal orifices location according to number of roots in mandibular first molars
Authors: Jang Ji-Hye , Kim Jin-Woo , Cho Kyung-Mo , Kim Soo-Yeon , Park Se-Hee
Published: August 2024

Objectives: The purpose of this study was to investigate the ratio of 4 root canals and the incidence of Radix Entomolaris in mandibular first molars and find out anatomical difference according to number of roots by analysis of cone-beam CT images in a Korean population. Materials and Methods: Total 142 images containing mandibular first molars were selected from CBCT images taken from 2013 to 2017 at Gangneung-Wonju National University Dental Hospital. After reconstructing the image with reference to the Cemento-enamel junction, the root canals were detected at the bottom of the pulpal floor and the number of roots and root canals were analyzed. Various lengths and MLO-DLO-DBO angle were measured between each canal orifices and the external contour line of the tooth, and the distolingual canal wall thickness was measured. Student t-test was used for statistical significance. Results: Among the total 142 teeth, 4 canals were 42.2% and Radix Entomolaris was 25.3%. As the results of measuring various lengths and the angle, the distolingual canal orifice in Group 2(with Radix Entomolaris) tends to deviate to the lingual side than the mesiolingual canal orifice and to the mesial side than the distobuccal canal orifice. Besides, thickness of the distolingual canal wall in Group 2(with Radix Entomolaris) was significantly thinner than that of Group 1 at every level except pulpal floor level. Conclusion: It is necessary to consider the difference according to the presence of Radix Entomolaris in endodontic treatment.
Caries preventive effect from community water fluoridation program
Authors: Ha Tae-Gyu , Kong Wook-Sung , Kim Se-Yeon , Kim Ji-Soo , Lee Jung-Ha , Kim Han-Na , Kim Jin-Bom
Published: August 2024

Objectives: The water fluoridation program has been implemented since 2008 at the Daesan water treatment plant, Changwon City. The aim of this study is to evaluate caries preventive effect of permanent teeth from community water fluoridation program Methods: Evaluation surveys were conducted on 8-, 10- and 12-year olds in the fluoridated and non-fluoridated area of Uichang-gu and Seongsan-gu, Changwon City in 2015. The number of the subjects in 2015 was 722 in fluoridated area and 707 in non-fluoridated area. The caries preventive effect of permanent teeth by community water fluoridation was estimated by the differences in adjusted DMFT and DMFS scores between the program and control groups. Cofounders of mean number of fissure-sealed teeth or surfaces, and number of subjects by gender were adjusted to estimate the caries preventive effect of permanent teeth. Results: The mean DMFT score or DMFS score of children aged 8-, 10- and 12-years adjusted for the number of fissure-sealed teeth or surfaces in fluoridated area were significantly lower than those in non-fluoridated area in 2015. The caries preventive effect of permanent teeth estimated based on the difference of mean DMFT scores adjusted for fissure-sealed teeth, age and number of subjects by gender between control and program group among children was 37.3%. Conclusions: These results suggest that the caries preventive effect of permanent teeth from water fluoridation program at Daesan water treatment plant, Changwon City was so high that the water fluoridation program should be developed in other regions in Korea.
Mouthguard and Sports Dentistry: a perspective for the future
Authors: Ryu Jae Jun , Lee Soo Young
Published: August 2024

Conventional mouthguard fabrication process which consists of elastomeric impression taking and followed gypsum model making is changing into intraoral scanning and dental model printing with 3D printer. In addition, new 3D printing materials for mouthgurad, 3D Computer-Aided Design(CAD) software for dental appliance, evaluation of a virtual dentoalveolar model for testing virtually 3D designed mouthguard, and lightweight sensor technology will lead dental professionals to the new era of Sports Dentistry, including information technology integrated custom mouthguard fabrication and creating value with analytic data acquired from sensors in mouthguard.
Subcutaneous emphysema during removal of suture after intraoral surgery
Authors: Park Jong-Chan , Shin Hyeon-Seo , Son Jeong-Wan , Lee Jun , Kim Bong-Chul , Lim Hun-Jun
Published: August 2024

Subcutaneous emphysema is relatively rare postoperative complication in the oral and maxillofacial region. Most cases reported in maxillofacial area relate to the use of high-speed handpiece. However, in this case, subcutaneous emphysema was caused by compressed air blow performed during suture removal. Cone-Beam Computed Tomography was conducted to evaluate the extent of diffusion bubbles.. In this report, we describe etiology, diagnosis, prevention and management of subcutaneous emphysema in the maxillofacial area.
Dental biofilm control of the disabled patients
Authors: Cho Hyun-Jae
Published: August 2024

Dental caries and periodontitis are the major concerns of oral disease to human, and its etiologic factor is dental biofilm. The aim of this study is to discuss the clinical application method and the meaning of dental biofilm control in the disabled patients. Generally, ultrasonic scaler are likely to generate excessive stimulus to the disabled patients. Rubber cup application using Ni-Ti engine could remove dental biofilm more comfortably to the disabled patients.
K-point stimulation: triggering the jaw opening reflex for brain-damaged patients
Authors: Hyun Hong-Keun
Published: August 2024

Patients with a wide range of cerebrovascular disease may have difficulty in opening their mouths, resulting in failing to swallow foods and maintain their oral hygiene. K-point was introduced as an effective trigger point to stimulate the jaw opening reflex for those patients. K-point stimulation may be useful as one of methods of helping open the jaw for dental examinations, or for placing foods onto the dorsum of the tongue and swallowing them effectively. Although this method cannot always guarantee the success of the jaw opening for every patient, it may still be considered to be an effective one to apply to patients having difficulty in jaw opening and swallowing disorder.
A report on the regional oral health centers for the disabled in Korea
Authors: Go Hyeon-Jeong , Park Tae-Jun , Kim Eun-Kyong , Jo Han-Jin , Choi Youn-Hee , Song Keun-Bae
Published: August 2024

Purpose : The purpose of this study was to survey the present status of the regional oral health centers for the disabled. Material and methods : Face to face interviews with oral healthcare professionals in eight regional oral health centers and literature reviews were conducted among eight regional oral health centers for the disabled during 2, July to 30, August 2017. Results : It is necessary to establish more regional oral health centers for the disabled in area where the number of disabled person as percentage of whole region population is high. Also, all the centers appeared a lack of professional manpower including dentist, dental hygienist and anesthesiologist, equipment and facilities for the demands of patients and their guardians. It is essential for the government to improve the support system to regional oral health centers for the disabled. Conclusions : This study can be used as a reference for the countermeasure to make a new policy and activate the accessibility of dental care services in the public for the disabled.
Analysis of Various Influencing Factors Related to Patient-Dentist Interaction Score
Authors: Kim Jooah , Kim Kee-Deog , Jo Jaehyun , Huh Jisun , Jung Seoyeon , Lee Bora
Published: August 2024

Each college of dentistry in Korea is examining and reorganizing its own curriculum to prepare students for the practical examination of the National Dental Licensing Examination. Conducting an assessment of students' competency of communication skills with standardized patients is the first attempt for the examination. Yonsei University College of Dentistry carried out the evaluation of communication attitude, communication written exam, and communication skills practice with standardized patients for Third year predoctoral students. The purpose of this study is a) to find out the relationship between the variables measured in communication skills education and b) to make a new basis for the application of communication education and evaluation in dentistry. Based on the results of the study, the following suggestions for the operation of a dental communication curriculum can be drawn: First, the communication classes and the practice with standardized patients should be based on the wide support of the school. In addition, the patient-dentist interaction (PDI) should be practiced in the same way as practically possible by predoctoral students. Moreover, a space is required to allow predoctoral students to practice PDI. Second, the communication score given by the standardized patients was the most influential on the total score of PDI. This indicates that the communication practice with the standardized patients for the practical examination of the National Dental Licensing Examination is a meaningful process in the course of its communication education.
Improvement of Accessibility to Dental Care due to Expansion of National Health Insurance Coverage for Scaling in South Korea
Authors: Huh Jisun , Nam SooHyun , Lee Bora , Hu Kyung-Seok , Jung Il-Young , Choi Seong-Ho , Lee Jue Yeon
Published: August 2024

Since 2013, adults aged over 20 can receive national health insurance scaling once a year in South Korea. In this study, we analyzed the usage status of national health insurance care service for periodontal disease in 2010-2018 by using Healthcare big data of the Health Insurance Review and Assessment Service. The increase rate of the dental care users was very high at 7.8 and 11.2% in 2013 and 2014, respectively. These are higher than the increase rate of all medical institution users, which is between -1.7 and 3.7%. In 2017, the rate of dental use was 44.4%, which has increased more than 10% compared to 2012. Percent receiver of national health insurance scaling was 19.5% in 2017. The 20s had the highest rate of 23.2%. The rate decreased with age. Based on these results, it can be evaluated that the expansion of national health insurance coverage for scaling improves accessibility to dental care. A more long-term assessment of the effect of periodic dental examination and scaling on reducing the prevalence of periodontal disease is needed. National health insurance coverage should be extended to oral hygiene education and supportive periodontal therapy in order to prevent periodontal disease.
Clinical considerations in the use of dental light curing unit
Authors: Lee Chang-Ha
Published: August 2024

Increasing the aesthetic needs of patients and decreasing the use of amalgam had led to increased demand for dental resin composite. Thereby, light curing unit (LCU) has become an essential equipment in dental clinic. To ensure long-term prognosis of photopolymerized materials, LCU should have a uniform and consistent radiant output and an emission spectrum that includes the active wavelength range of photoinitiators. In addition, when the correct use and thorough maintenance and repair of LCU are performed, the higher success rate of restoration using photopolymerization materials will be achieved.
Classification of maturation of bacterial dental deposits using differences in fluorescence intensity
Authors: Cho Mu-Yeol , Lee Eun-Song , de Jong Elbert de Josselin , Yoon Hong-Chul , Kim Baek-Il
Published: August 2024

Purpose: The aim of this study was to evaluate the red fluorescence characteristics of bacterial dental deposits assessed by quantitative light-induced fluorescence (QLF) technology and confirm whether the red fluorescence can distinguish and evaluate quantitatively accumulation of bacterial dental deposits. Methods: This retrospective cross-sectional study used QLF images captured at a dental clinic from January to December 2016. In each QLF image, a skilled examiner selected one region where the presence of deposits was suspected. Then, the regions were classified into three groups of not detectable deposits(ND), half detectable deposits (HD), and full detectable deposits (FD) by two examiners according to classification criteria. Only those images where the regions of bacterial dental deposits were classified identically by all examiners were used for analysis. The mean red fluorescence intensity (RFI) was defined as the mean value of R/G for all pixels in the regions. The RFI was compared between groups using Welch's ANOVA test, and the Spearman correlation was calculated to assess the association between RFI and accumulation of deposits. Results: In this study, 351 images among the collected images of 605 subjects were finally selected. The mean age of subjects was about 44 years. The R/G values of the ND, HD and FD were 0.73, 1.26 and 1.83 respectively. There were significant differences between all groups (p<0.001), and strong positive correlation was identified between the R/G value and the accumulation of deposits (r = 0.90, p<0.001). Conclusion: The intensity of red fluorescence as observed in the QLF images correlated well with the accumulation maturation of the deposits, which indicates that the QLF technology can be used to evaluate the status of oral hygiene.
Effects of auditory feedback and task difficulty on the cognitive load and virtual presence in a virtual reality dental simulation
Authors: Kim Byunggee , Yang Eunbyul , Choi Namki , Kim Seonmi , Ryu Jeeheon
Published: August 2024

This research examined the difference in cognitive load and the virtual presence depending on auditory feedback and task difficulty in haptic-based dental simulation. In the field of dental education, practice-centered training using handpiece has been crucial because a practitioner's psychomotor experience has a significant impact on the mastery of treatment skills. For the novice, it is necessary to reduce errors in dental treatment to enhancing skill acquisition in the haptic practice. In the training process, the force-feedback is crucial to elaborate subtle movement to guide what to do and how it should be hard or soft. However, It is not easy to add force-feedback to generate kinetic experience training. As an alternative method, we examined that auditory feedback can help learners' skill training. In this study, we analyzed how the presence/absence of auditory feedback at the different levels of task difficulty impacts learners' psychological demand and virtual presence in the virtual reality simulation. For this study, 29 dental college students participated in a dental simulation. The participants were grouped into two conditions that are with and without auditory feedback. Additionally, two consecutive tooth preparation tasks with different levels of difficulty were used in the simulation. The auditory feedback condition gives alarms to a learner when he treats a non-targeted tooth with a virtual handpiece. The user's cognitive load and virtual presence were measured to examine the effects of auditory feedback. The results revealed that the main effect was found in cognitive loads. Also, a significant interaction effect was shown in the virtual presence. We discussed the effective design methods for the virtual reality-based dental simulation through the result of this study.
Effect of primer on the polymerization of dual cure resin cements
Authors: Lee Eun-Hye , Enkhbileg Nyamsuren , Kim Jin-Woo , Cho Kyung-Mo , Park Se-Hee
Published: August 2024

Objectives: The primer (G-Cem One Adhesive Enhancing Primer), which promote self-polymerization more in the absence of polymerization light is developed. To date, many studies on the mechanical properties and prognosis of various self-adhesive resin cements have been published. Since there is almost no comparison of the degree of polymerization depending on the application of primers, this study was attempted. Materials and Methods: A total of three types of dual cure self-adhesive resin cements (G-Cem One, G-Cem LinkAce, Rely-X U200) and one type of dual cure resin cement (Rely-X Ultimate) were evaluated. G-Cem One Primer was used as a primer enhancing of auto-polymerization. A mold 5 mm in diameter and 2 mm thick was made from aluminum, primers were applied on a glass slit, and each material was filled in the mold, and self-polymerization was induced. The microhardness was measured with a Vickers microhardness machine after 10 minutes, 1 hour,3 hours,6 hours and 24 hours. All dates were statistically analyzed. Results: G-Cem One, G-Cem LinkAce and Rely-X U200 showed high microhardness values when primers were applied at the beginning of cement mixing. Primer application did not show significantly different in Rely-X Ultimate. Conclusion: The application of a new primer has a dual cure self-adhesive resin cement which promotes the polymerization at the beginning of the mixing.
Frailty in older people and oral frailty
Authors: Jung Hoi In
Published: August 2024

With a dramatic increase in the older population, there is a growing interest in strategies for managing oral disorders in the elderly. This study aims to introduce oral frailty and propose dental and oral health services for older people. This study reviewed the literature on oral frailty and frailty in older people by searching academic databases, government documents, and related websites. There is a growing awareness that the recovery and maintenance of oral function help delay the onset of frailty and conditions requiring nursing care, thereby extending a healthy life expectancy. The Japanese Society of Gerodontology (JSG) proposed the concept of oralhypofunction. JSG defined oral hypofunction as a presentation of 7 signs or symptoms: oral uncleanness, oraldryness, a decline in occlusal force, decline in the motor function of the tongue and lips, decrease in tongue pressure, decline in chewing function, and reduction in the swallowing function. JSG suggested diagnosing oral hypofunction if the criteria for three or more signs or symptoms are met. More evidence should be gathered from clinical studies and trials in the Korean community care setting to develop better diagnostic criteria and management strategies for the Korean elderly. Better health in older people can be achieved by strengthening the dental and oral health provider’s accountability of healthcare systems. The evolving concept of oral frailtypaves the way for effective dental care for the elderly in Korea.
Intraosseous neurofibroma of the mandible involving masticator space
Authors: Kim Eun-Kyung , Han Won-Jeong , Choi Jin-Woo , Kim Hak-Sun
Published: August 2024

Neurofibroma is a benign, heterogenous peripheral nerve sheath tumor arising from the connective tissue of peripheral nerve sheaths, especially the endoneurium. Its intraoral occurrence is uncommon and its occurrence within mandible is extremely rare. A case of solitary intraosseous neurofibroma of the mandible involving masticator space in a 8-year-old male is reported. He was referred from a private local clinic with a chief complaint of limitation in opening of the mouth. Panoramic and cone-beam computed tomographic images showed unilocular radiolucent lesion with scalloped border at the right mandibular ramus, connected posteriorly to the enlarged mandibular foramen and anteriorly to the mandibular canal. T1-weighted magnetic resonance images showed soft tissue mass of isointensity compared with muscles. Contrast-enhanced T1-weighted images showed peripheral enhancement and T2-weighted images showed the heterogeneous hyperintense mass with extension between lateral and medial pterygoid muscles. The tumor was surgically removed under general anesthesia and diagnosed to be neurofibroma at the biopsy.
Dental treatment and Oral hygiene management for the disabled
Authors: Kwak Eun-Jung
Published: August 2024

Dental treatment for the disabled requires special consideration. Due to poor cooperation of the patient during dental procedures, behavioral management or general anesthesia is often necessary. We also need to considerthe patient’s oral habits and ability to maintain oral hygiene. Since dental treatment may be difficult for thedisabled, prevent is more important than treatment itself. In addition, secondary dental caries and periodontaldisease after treatment are likely to occur when proper oral care is not sustained. Because the patient is difficultto maintain optimal oral hygiene by themselves, it is essential to educate the guardian about the importance of oral hygiene, as well as encourage them to participate in the patient’s daily oral care. Finally, it is necessary to regularly check the patient’s oral hygiene status and perform professional plaque control through frequent dental visit.
Baseline neutrophil-to-eosinophil-ratio and outcome in metastatic clear-cell renal cell carcinoma treated with nivolumab or ipilimumab/nivolumab
Authors: Beulque Yana , Kinget Lisa , Roussel Eduard , Mobaraki Sajedeh , Laenen Annouschka , Debruyne Philip R. , Van Herck Yannick , Baldewijns Marcella , Wozniak Agnieszka , Garg Abhishek D. , Zucman-Rossi Jessica , Couchy Gabrielle , Albersen Maarten , De Wever Liesbeth , Haaker Lorenz , Beuselinck Benoit
Published: August 2024

Background and purpose: This study aims to evaluate neutrophil-to-eosinophil ratio (NER) as a prognostic and/or predictive biomarker in metastatic clear cell renal cell carcinoma (m-ccRCC) treated with nivolumab or ipilimumab/nivolumab.
Patients/materials and methods: We performed a retrospective study on m-ccRCC patients treated with nivolumab or ipilimumab/nivolumab (2012–2022). Baseline NER was calculated and correlated with clinical outcomes: response rate (RR), progression free survival (PFS) and overall survival (OS). Corresponding transcriptomic data were analysed.
Results: We included 201 m-ccRCC patients, 76 treated with ipilimumab/nivolumab and 125 with nivolumab. Baseline NER was statistically significantly associated with International Metastatic RCC Database Consortium (IMDC) risk groups. Increased NER was associated with shorter PFS and OS in the total patient series and nivolumab-treated patients. In patients treated with ipilimumab/nivolumab, increased NER was only statistically significantly associated with shorter OS. The impact of baseline NER on PFS and OS was independent of IMDC risk stratification. No clear correlation was found between baseline NER and RECIST response or maximal tumour shrinkage. In two additional databases, NER was also associated with PFS and OS in first-line vascular-endothelial-growth-factor-receptor tyrosine-kinase-inhibitors (VEGFR-TKIs), but not to disease-free survival in the post-nephrectomy setting. Lower NER was associated with intratumoural molecular features possibly associated with better outcome on immune checkpoint inhibitors.
Interpretation: Lower baseline NER is associated with better PFS and OS, independent of IMDC risk score, in m-ccRCC patients treated with ipilimumab/nivolumab or nivolumab. It correlates with intratumoural molecular features possibly associated with better outcome on immune checkpoint inhibitors. The predictive power of this biomarker is probably limited and insufficient for patient selection.
Multi-disciplinary team meetings for lung cancer in Norway and Denmark: results from national surveys and observations with MDT-MODe
Authors: Gouliaev Anja , Berg Janna , Bibi Rana , Arshad Arman , Leira Håkon Olav , Neumann Kirill , Aamelfot Christina , Christense Niels Lyhne , Rasmussen Torben R.
Published: August 2024

Background and purpose: Multi-disciplinary Team (MDT) meetings are widely regarded as the ‘gold standard’ of lung cancer care. MDTs improve adherence to clinical guidelines for lung cancer patients. In this study, we describe and compare lung cancer MDTs in Denmark and Norway by combining national surveys and the MDT-Metric for the Observation of Decision-making (MDT-MODe) instrument.
Materials and method: Identical surveys were sent out to all lung cancer MDT centers in Denmark and Norway by the Danish Lung Cancer Group and the Norwegian Lung Cancer Group. Six MDT centers, three in Denmark and three in Norway, were observed using the MDT-MODe instrument.
Results and interpretation: We found similar organization of MDT meetings in both countries, with the main difference being more local MDT meetings in Norway. All lung cancer MDTs were chaired by respiratory physicians and attended by a radiologist. Other members included oncologists, pathologists, thoracic surgeons, specialist nurses, nuclear medicine specialists and junior doctors. Overall, members reported that they had sufficient time for preparation and attending MDT meetings. With the MDT-MODe instrument it was found that the MDT chairs, surgeons, oncologists, radiologists all contributed positively to case discussion. Comorbidities were included in the discussion of most patients while the patient’s view and psychosocial issues were less often discussed. A treatment decision was reached in 79.7% of cases discussed. In conclusion, we found similar settings and overall good quality concerning lung cancer MDT meetings in Denmark and Norway.
Parametric study of the laser energy absorption in high-power laser beam welding
Authors: Meng Xiangmeng , Putra Stephen Nugraha , Bachmann Marcel , Rethmeier Michael
Published: August 2024

Laser energy absorption on the keyhole wall is decisive for the thermodynamic behavior and the resultant weld properties in the high-power laser beam welding process. However, its highly transient nature on a microsecond scale makes the quantitative analysis challenging. In this paper, the influence of the relevant welding parameters on laser energy absorption is studied statistically by utilizing multiphysical modeling, in which the three-dimensional transient keyhole dynamics and thermo-fluid flow are calculated. A dynamic mesh adaption technique and a localized level-set-based ray-tracing method are employed to improve the model accuracy further. The results show that the focus position has a remarkable effect on the time-averaged laser absorption, and in contrast, the laser energy distribution regime is only slightly influenced by the welding speed in the studied parameter range (1.5–3.0 m/min). The absorption ratio of the laser energy on the keyhole front wall decreases with increasing welding speed and increases with upward-moving focus positions. The comparison between the calculated results and the experimental measurements ensures the validity of the proposed model.
Mejora de la escritura académica a través de estrategias metacognitivas: una revisión sistemática de la evidencia empírica
Authors:   Universidad Nacional Mayor de San Marcos, López Chumbe Mark
Published: August 2024

El objetivo de este estudio fue realizar una revisión exhaustiva de las investigaciones existentes sobre el uso de estrategias metacognitivas en la escritura académica, empleando la metodología PRISMA. La evaluación se realizó mediante la búsqueda en las bases de datos Scopus, Web of Science y Scielo de artículos pertinentes publicados entre 2013 y 2023. Los resultados validaron la importancia y eficacia de las estrategias metacognitivas en el ámbito de la escritura académica. Este artículo enfatiza la importancia de promover la enseñanza y utilización de habilidades metacognitivas para mejorar la escritura académica de los estudiantes