VGG-16 딥러닝 알고리즘을 활용한 우식치아와 건전치아 분류

변민지 ( Min-ji Byon ),전은주 ( Eun-joo Jun ),김지수 ( Ji-soo Kim ),황재준 ( Jae-joon Hwang ),정승화 ( Seung-hwa Jeong ) 대한예방치과·구강보건학회 2021 大韓口腔保健學會誌 Vol.45 No.4

Objectives: Diagnosis of dental caries is based on the dentist’s observation and subjective judgment; therefore, a reliable and objective approach for diagnosing caries is required. Intraoral camera images combined with deep learning technology can be a useful tool to diagnose caries. This study aimed to evaluate the accuracy of the VGG-16 convolutional neural network (CNN) model in detecting dental caries in intraoral camera images. Methods: Images were obtained from the Internet and websites using keywords linked to teeth and dental caries. The 670 images that were obtained were categorized by an investigator as either sound (404 sound teeth) or dental caries (266 dental caries), and used in this study. The training and test datasets were divided in the ratio of 7:3 and a four-fold cross validation was performed. The Tensorflow-based Python package Keras was used to train and validate the CNN model. Accuracy, Kappa value, sensitivity, specificity, positive predictive value, negative predictive value, ROC (receiver operating characteristic) curve and AUC (area under curve) values were calculated for the test datasets. Results: The accuracy of the VGG-16 deep learning model for the four datasets, through random sampling, was between 0.77 and 0.81, with 0.81 being the highest. The Kappa value was 0.51- 0.60, indicating moderate agreement. The resulting positive predictive values were 0.77-0.82 and negative predictive values were 0.80-0.85. Sensitivity, specificity, and AUC values were 0.66-0.74, 0.81-0.88, and 0.88-0.91, respectively. Conclusions: The VGG-16 CNN model showed good discriminatory performance in detecting dental caries in intraoral camera images. The deep learning model can be beneficial in monitoring dental caries in the population.

대사증후군 요소와 치주염의 관련성: 35-79세 한국인

김지수 ( Ji-soo Kim ),김세연 ( Se-yeon Kim ),변민지 ( Min-ji Byon ),이정하 ( Jung-ha Lee ),정승화 ( Seung-hwa Jeong ),김진범 ( Jin-bom Kim ) 대한예방치과·구강보건학회 2019 大韓口腔保健學會誌 Vol.43 No.3

Objectives: The purpose of this study was to investigate the association between the components of metabolic syndrome (MetS) (waist circumference, hyperglycemia, hypertriglyceridemia, low levels of high-density lipoprotein cholesterol, and hypertension) and periodontitis in Korean adults aged 35-79 years. Methods: In this study, data from the Sixth Korean National Health and Nutrition Examination Survey (KNHANES, 2013-2015) were analyzed. Among the 22,948 participants of the Sixth KNHANES, 8,314 participants, who were aged 35-79 years and had completed all systemic and oral health examinations and questionnaires, were included in this study. Confounding variables associated with the demographics and socioeconomic status and systemic and oral health-related behaviors were age, gender, household income, the educational level, smoking and drinking habits, the physical activity status, and frequency of daily toothbrushing. The independent variables were components of MetS, and the dependent variable was periodontitis. Results: Periodontitis was diagnosed in 37.0% of the participants. The incidence of periodontitis among participants with MetS was 47.9%. The incidences of periodontitis among participants with three, four, and five components of MetS were 44.8%, 50.0%, and 56.2%, respectively. The odds ratio (OR) for periodontitis among participants with MetS was 1.43 (95% confidence interval [CI]: 1.27-1.61). The participants with three, four, and five components of MetS showed a significantly higher OR for periodontitis than those with no components of MetS (three components, OR=1.18, 95% CI: 1.02-1.36; four components, OR=1.34, 95% CI: 1.14-1.59; five components, OR=1.68, 95% CI: 1.29-2.20). Conclusions: A higher number of components of MetS augments the OR of periodontitis.

불소바니시 5종의 불소이온용출량 비교: 실험실 연구

김지수 ( Ji-soo Kim ),변민지 ( Min-ji Byon ),남용태 ( Yong-tae Nam ),김진범 ( Jin-bom Kim ),정승화 ( Seung-hwa Jeong ) 대한예방치과·구강보건학회 2019 大韓口腔保健學會誌 Vol.43 No.4

Objectives: This study aims to compare the fluoride-release between different fluorine varnish under in vitro experimental conditions. Methods: In this study, 5 fluoride varnish products distributed in Korea were selected. V-varnishTM (Vericom, Korea: VV), CavityShieldTM (3M ESPE, USA: CS), ClinproTM White varnishTM (3M ESPE, USA: CP), MI VarnishTM (GC, Japan: MI), and Fluor Protector (Ivoclar Vivadent, Liechtenstein: FP). For the in vitro study, 10 mg of each fluoride varnish was thinly applied to the same area of the specimen. The specimen was then immersed in 3 ml of distilled water at consistent intervals to confirm fluoride release. Nine specimens per group were used. Fluoride ion electrodes were used to measure the fluoride concentration of the solution. The Kruskal-Wallis nonparametric test was performed to compare between each experimental group, and the Wilcoxon signed-rank nonparametric test was performed to compare experimental groups over time. The significance level for a Type I error was set at 0.05. All statistical analyses were performed using SPSS 25.0 (IBM Co., Armonk, NY, USA). Results: In vitro experiments showed that the amount of fluoride released from MI was higher than the other groups during the first 12 hours after application. However, the amount of fluoride released from CP and CS was higher than MI as the immersion time increased over 12 and 20 hours, respectively. The fluoride release from FP was the lowest at all measurement points. Conclusions: The results of this study showed that the remaining fluoride effect from rosin type fluoride varnishes was higher than liquid type fluoride varnishes. There were differences in the residual fluoride concentrations despite each fluoride varnish having the same fluoride content.

경상남도 합천군 합천읍 수돗물불소농도조정사업의 18년간 영구치우식 예방효과

김지수 ( Ji-soo Kim ),변민지 ( Min-ji Byon ),전은주 ( Eun-joo Jun ),정승화 ( Seung-hwa Jeong ),김진범 ( Jin-bom Kim ) 대한예방치과·구강보건학회 2020 大韓口腔保健學會誌 Vol.44 No.4

Objectives: The water fluoridation program in Hapcheon township area has been implemented since 2000. This study aimed to evaluate the caries-preventive effect of water fluoridation on permanent teeth after implementation of an 18-year community water fluoridation program in a suburban area. Methods: A survey was conducted in 2018 with 359 subjects, aged 8, 10, and 12 years, residing in the Hapcheon township area. In this prospective cohort study, the data on caries prevalence obtained from 671 subjects, aged 8, 10, and 12 years, in 2000, when the community water fluoridation program was initiated in the township, were used as a cohort to evaluate the caries-preventive effect after 18 years. The caries-preventive effect of community water fluoridation on permanent teeth was estimated by comparison of the adjusted DMFT scores between the program and the control group, and between the pre- and post-program data after 18 years. The confounding factor, mean number of fissure-sealed teeth, was adjusted to estimate the caries-preventive effect of fluoridation on permanent teeth. Results: Based on the results of the surveys conducted in Hapcheon-eup in 2000 and 2018, the mean number of fissure-sealed permanent teeth was 2.24 in 2000 and 1.38 in 2018. The mean DMFT scores of subjects aged 8, 10, and 12 years in 2018, adjusted for fissure-sealed permanent teeth in the fluoridated area, were significantly lower than those reported by the 2018 Korea National Children’s Oral Health Survey. In addition, the mean values of the adjusted DMFT scores of subjects aged 8, 10, and 12 years in 2018, after the 18-year fluoridation program, were significantly lower than those reported in 2000, the year the fluoridation program was initiated. Conclusions: Community water fluoridation has a high caries-reducing effect; thus, the reintroduction of water fluoridation program is desirable to prevent dental caries.

청소년들의 치주건강과 관련된 위험요인

김지수 ( Ji-soo Kim ),김세연 ( Se-yeon Kim ),변민지 ( Min-ji Byon ),전은주 ( Eun-joo Jun ),정승화 ( Seung-hwa Jeong ),김진범 ( Jin-bom Kim ) 대한예방치과·구강보건학회 2020 大韓口腔保健學會誌 Vol.44 No.3

Objectives: The purpose of this study was to investigate the risk factors related to periodontal health in middle school and high school adolescents. Methods: This study was conducted using data from the Sixth Korean National Health and Nutrition Examination Survey (KNHANES, 2013-2015). Among the 22,948 participants in the Sixth KNHANES, 1,222 participants (aged 12-18 years) who completed the systemic and oral health examinations and questionnaires were included in this study. Independent variables related to demographic socioeconomic status and oral health-related behaviors were the following: age, gender, household income, frequency of daily toothbrushing, smoking, alcohol drinking, annual dental visit, and periodontal treatment. The dependent variables were the prevalence of gingival bleeding or calculus and the number of sextants with gingival bleeding or calculus.. Results: Among the total participants, 34.1% were diagnosed with prevalence of gingival bleeding or calculus, and periodontal health was found to be at its worst at 17 years of age (41.6% of participants). Moreover, household income, alcohol drinking, annual dental visits, and frequency of daily toothbrushing were related to prevalence and the number of sextants with gingival bleeding or calculus. The adjusted odds ratio (aOR) for prevalence of gingival bleeding or calculus by alcohol consumption, toothbrushing less than twice per day, and number of DMFT were 5.00 (95% CI: 2.24- 11.18), 2.21 (95% CI: 1.21-4.04), and 1.09 (95% CI: 1.02-1.17), respectively. Conclusions: To prevent periodontal disease among adolescents, it is necessary to improve oral health-related behavior and its associated factors and continuous oral health education.

아크릴과 분광광도계를 이용한 치약마모도 평가

정승화 ( Seung-hwa Jeong ),변민지 ( Min-ji Byon ),전은주 ( Eun-joo Jun ) 대한예방치과·구강보건학회 2023 大韓口腔保健學會誌 Vol.47 No.4

Objectives: This study aimed to develop a method for objectively evaluating toothpaste abrasivity, enabling a direct comparison between different toothpastes. Methods: Nine commercially available toothpaste variants were selected, and 8 mm thick acrylic specimens were allocated to each toothpaste treatment group (n=7). A control group without toothpaste was also included. Specimens and toothbrushes were mounted on the V8 Cross brushing machine, and toothpaste (0.05-0.1 g) was applied for 20 strokes under a 200 g load and 1 Hz speed. The surface wear was measured at an absorbance of 600 nm in a UV-Vis spectrophotometer. Specimens were then photographed with a polarized light microscope, and the gray value of the worn brushed part was obtained through image analysis using Image J software. A one-way ANOVA followed by Bonferroni’s post-hoc test was employed for analyzing absorbance and gray value differences among the toothpaste groups. The correlation between absorbance and gray value was assessed using Pearson’s correlation analysis. Results: Significant differences were noted in absorbance and gray values across the toothpaste groups (P<0.05), and a strong correlation was observed between the absorbance and the values from the images analyzed (r=0.948, P<0.001). The wear rankings based on absorbance and image analysis values were mostly the same. Conclusions: This study introduces a direct and objective method for evaluating toothpaste abrasion, offering users objective information on different toothpaste types.

치은염과 치석보유 상태를 중심으로 한 12세 아동들의 치주상태와 관련 요인

이정하 ( Jung-ha Lee ),김세연 ( Se-yeon Kim ),김지수 ( Ji-soo Kim ),변민지 ( Min-ji Byon ),전은주 ( Eun-joo Jun ),김한나 ( Han-na Kim ),김진범 ( Jin-bom Kim ) 대한예방치과·구강보건학회 2019 大韓口腔保健學會誌 Vol.43 No.4

Objectives: This study aimed to investigate factors related to the periodontal health of 12-year-old children. Methods: In 2015, the Korean Children’s Oral Health Survey from the Ministry of Health & Social Welfare conducted a nationwide representative sample comprised of 23,702 12-year-old children. The calibration-trained dentists examined the gingivitis and dental calculus of the children taking into consideration of the Löe and Silness gingival index to diagnose gingivitis with a modified gingivitis scale. We used questionnaires to collect data from the children on dental treatments, the experience of dental pain and gingival bleeding, self-perceived oral health, and oral health behaviors. Data were analyzed using a complex samples Chi-square test, general linear model, and logistic regression. Significance was determined at P<0.05. Results: The prevalence of gingivitis was higher among males (OR 1.57), among children with poor perception (OR 1.19), dental calculus (OR 3.68), or gingival bleeding experience (OR 2.00), and among children not using dental floss (OR 1.69) or tongue cleaner (OR 1.90). The prevalence of dental calculus was higher among children with gingivitis (OR 3.82) and among children who had not visited a dental clinic in the preceding year (OR 1.31). However, dental calculus was lower among children with a higher frequency of daily toothbrushing (OR 0.75), intake of cariogenic foods (OR 0.90), or a higher DMFT index (OR 0.91). Conclusions: Children with dental calculus and gingival bleeding who did not visit a dental clinic in the preceding year also had a higher prevalence of gingivitis and dental calculus. The prevalence of children’s dental calculus was lower among children with a high frequency of daily toothbrushing.