Dental Maturation in Canadian Children – A Cross-country Comparative Study

Objectives: Our study investigated radiographic root maturation of 6 to 13 years old British Columbian (BC) children compared to the dental maturation of Quebec (QC) children. Demirjian et al. 1973 performed the first such radiographic study on French-Canadian children. Root completion is thought to be largely under genetic control, but there is evidence that envirnmental factors also play a role. We asked whether a multi-ethnic population, such as the population of BC may have different characteristics than one from QC where immigration is a more recent phenomenum. Our goal was to determine whether it is time to revise dental age standards so that they are more reflective of the multi-cultural make-up of Canada today.
Methods: Panoramic radiographs of 100 boys and girls (N=200) were identified from a retrospective chart review. BC children were born between 1969 and 1980. QC children were born in the 1960's. Dental age was assessed according to Demirjan’s method (1973): Scores of maturity (A-H) were given for 7 mandibular teeth and used to calculate an overall dental maturity score for each child. BC values were compared to the 50th percentiles for the QC children for each age band (6-7, 7-8, 8-9, 9-10, 10-11, 11-12, 12-13 years).
Results: The dental maturity of children aged 8 and up were no different between BC and QC. Boys were always significantly delayed compared to girls. The BC girls aged 6-7 (p <0.0001) and 7-8 years (p<0.05) were significantly advanced in dental maturity compared to QC girls. Boys were also significantly advanced between 6-7 and 7-8 years (p< 0.0001). The teeth that appeared to be advanced in BC compared to the norms were the lateral incisors.
Conclusions: Our study suggests that dental maturity standard curves developed by Demirjian are acceptable for measuring dental maturity of an ethnically heterogenous population of BC children from ages 8 onward. Future studies in multi-ethnic populations from other countries are necessary to confirm if the observed comparable dental development between homogenous and multi-ethnic populations are due to exposure to similar environmental factors. Human ethics approval #H1702181.