Age-related changes in the root canal system of permanent anterior teeth in Tibetan individuals

OBJECTIVES: This study aimed to assess age-related changes in pulp volume, volume ratio, buccolingual and mesiodistal diameter ratios, and the distance from foramen to apex in permanent anterior teeth of Tibetan individuals using micro-CT, and to evaluate the potential of these parameters as age estimation indicators. METHODS: A total of 121 permanent anterior teeth from Tibetan individuals (43 males and 78 females, aged 18 to 89 years) were analyzed with adjustment for tooth type as a covariate. Teeth were stratified into seven age groups and scanned using micro-CT. Measurements included pulp volume (PV), dentin volume (DV), volume ratio (VR = PV/DV), buccolingual ratio (BLR= inner/outer BL diameter), mesiodistal ratio (MDR=inner/outer MD diameter), and distance from foramen to apex (DFA). The Kruskal-Wallis H test was used to compare age group differences, followed by post-hoc pairwise comparisons with Bonferroni correction. Spearman's rank correlation and linear regression analyses were performed to evaluate associations between age and the measured parameters. RESULTS: PV, VR, BLR, and MDR all showed significant age-related decreases (all P < 0.05), with BLR demonstrating the strongest correlation (rₛ = -0.371). DFA showed no significant age-related change. The regression equation for BLR against age was y = 0.31107 - 0.00224x, with R² = 0.1380. CONCLUSION: In Tibetan permanent anterior teeth, PV, VR, BLR, and MDR decrease with age, with BLR showing the strongest correlation. BLR may serve as a supplementary age estimation marker when used in combination with other indicators.