Age Estimation Based on CBCT Measurement of Pulp Chamber Volume of the First Permanent Molar in Chinese Adults

Abstract

Abstract Purpose This study aims to establish a population-specific age estimation model by investigating the correlation between the volume of the right first permanent molar pulp chamber and the actual age of Chinese Han adults. Method A total of 1857 CBCT images of Han adult teeth (883 males, 974 females) from the Department of Stomatology of the Affiliated Hospital of North Sichuan Medical College were collected. The volume of the right first permanent molar pulp chamber was measured using Mimics software for statistical analysis. The data were divided into a training set and a validation set in an 8:2 ratio. An age estimation model was built using 1485 samples from the training set, and the accuracy of the model was verified with 372 samples. Results The volume of the right upper and lower jaw pulp chambers showed a strong negative correlation with age, with the correlation of the upper jaw volume with age being superior to that of the lower jaw, and the correlation was highest in the upper jaw of females (r = 0.880). There was a significant difference in the volume of the right first permanent molar pulp chamber between the upper and lower teeth positions and sexes (P < 0.05). Among the 11 mathematical models constructed, the cubic regression model was superior to the other models, and the cubic regression model built for the right upper first permanent molar in females was the best (AGE = 74.96−1.427X−0.04X2 + 0.001X3), with a mean absolute error (MAE) of 4.95 years. Conclusion In the process of age estimation, the volume of the first permanent molar pulp chamber has been proven to be an effective indicator. To improve the accuracy of age estimation, we recommend using models specific to gender and tooth type.