Influence of sex and timing of mixed dentition on discrepancies between chronological age and dental age in Taiwanese children

Background/purpose: The aim of this study was to determine the effects of age and sex on the difference between chronological age (CA) and dental age (DA) predicted using the Demirjian and Willems methods in Taiwanese children. Materials and methods: A total of 232 periapical X-ray images were obtained from children aged 5–12 years in Taiwan. Among them, 119 were boys, and 113 were girls. DA was calculated on the basis of the X-ray images of permanent teeth by using the aforementioned methods. The children were stratified by age (5–9 years [early mixed dentition period] vs. 10–12 years [late mixed dentition period]) and sex (boys vs. girls). Statistical analyses were performed to investigate potential age- and sex-based differences in the correlation between CA and DA. Results: No significant difference was observed between the mean CA and DA predicted using the Willems method in children with late mixed dentition and in girls. However, the correlation between CA and DA was stronger in children with early mixed dentition than in those with late mixed dentition and also stronger in boys than in girls. Conclusion: For children in mid-Taiwan, age and sex influence the development of permanent teeth. In addition, the correlation between DA and CA is relatively strong for boys in the early mixed dentition period.