S-Space College of Dentistry/School of Dentistry (치과대학/치의학대학원) Dept. of Dental Science(치의과학과) Theses (Master's Degree_치의과학과)
소아청소년기 상악 제일대구치 마모도 분석을 위한 종단 연구
Maxillary first molar wear: A longitudinal study of children
- 이승표; 박영석
- 치의학대학원 치의과학과
- Issue Date
- 서울대학교 대학원
- 학위논문 (석사)-- 서울대학교 대학원 : 치의과학과 구강해부학전공, 2016. 8. 박영석.
- OBJECTIVES: The aim of this study is to examine the correlation between tooth wear and age by quantitatively measuring maxillary first molar wear in Children.
METHODS: A total of 150 maxillary dental models were analyzed in 30 subjects (male: 11, female: 19) with an age range of 6-14 years. Dental models were analyzed in five groups divided according to age at 2-year intervals (i.e., 6, 8, 10, 12 and 14 years old). Stone casts of the maxillary dentition were rendered as virtual 3D models. Maxillary first molar wear were assessed based on area, volume and the shortest distance from the buccal occlusal plane to the central pit point (BCPH). The area and volume of the tooth cusps were measured at four different offset-plane heights (0.2, 0.4, 0.6, and 0.8 mm) and BCPH was measured using Rapidform 2004 software (INUS Technology Inc., Seoul, South Korea). Repeated measures analysis of variance (ANOVA) was performed to examine the relationship between age and the amount of wear, as quantified by area and
volume measurements. One-way ANOVA was used to analyze the relationship between age and BCPH. Correlation and regression analyses were also performed, and age estimation was obtained with linear regression analysis.
RESULT: Repeated measures ANOVA revealed significant differences between age and the amount of wear based on area, volume, and offset-plane height. Except age of 8 and 10, 12 and 14s 0.2-mm offset-plane-measured volume, all area and volume measurement of all ages and offset-plane height showed a significant amount of increase. Comparison of BCPH by age group showed that the 6-year-old age group was significant different from the 8-, 10-, 12- and 14-year-old groups. However, there were no significant differences between the 8-year-old age group and age groups 10 through 14. Upon using the BCPH to analyze the change in wear speeds, the following data were obtained: 91.23 μm/yr from 6 to 8 years
48.38 μm/yr from 8 to 10 years
4.10 μm/yr from 10 to 12 years
and 16.31 μm/yr from 12 to 14 years. Among age and measurement variables, the correlation coefficient was strongest when the volume was measured from the 0.4-mm offset-plane.
CONCLUSION: As age increases, the amount of wear, as quantified by area and volume measurements, also increases. Speed of wear gradually decreases with age, with the exception of a small increase from 12 to 14 years. According to this study, a regression equation that can be used for age estimation is: Age (y) = 0.16 × 0.4V + 0.85 (R2 = 0.49) using volume.