RÉSUMÉ
Objective:To investigate the correlation between root and root canal diameter of maxillary central incisors and age by cone-beam computed tomography(CBCT).Methods:CBCT images of 420 cases of Chinese Han population were divided into 7 age groups as follows:1 5 -24,25 -34,35 -44,45 -54,55 -64,65 -74 and 75 -84(n =60).Root diameter and root canal diameter of maxillary central incisors at the 3 /4 level from the cemenal-enamel junction(CEJ)to root apical were measured.Linear-regression a-nalysis was used to analyze the correlation between root and root canal diameter of the teeth and age,T-test was used to examine the gender difference.Results:Mean root diameter(mm)of the teeth in males and females were 5.81 ±0.445 and 5.53 ±0.489(P <0.05),mean root canal diameter(mm)1 .20 ±0.396 and 0.96 ±0.236(P <0.05),mean of the ratio of root canal diameter and root diameter of the teeth 0.21 ±0.072 and 0.1 7 ±0.043(P <0.05)respectively.There were negative correlations between the ratio of root canal diameter and root diameter of the teeth with age (R2 =0.576,P <0.05).Conclusion:The ratio of root canal diameter and root diameter of maxillary central incisors is negitively correlated with age in Chinese Han population.The decrease of root canal diame-ter in males is more significant than that in females.