Dental age estimation using radiographic assessment of third molar eruption among 10-20-year-old Ugandan population

Aim: This study aimed at establishing the age for third molar eruption among Ugandans aged 10-20 years.

Materials and methods: This was a cross-sectional study comprising 471 male and 541 female patients attending Mulago Dental Clinic. Patients' orthopantomographs were assessed for third molar eruption as described by Olze et al. Age was summarized using means/SD. Jaw and sex differences were assessed using Student's t-test.

Results: Complete eruption (Stage D) ranged between 13 and 20 years. The mean age at complete eruption for girls and boys was 17.5-18 years and 18.2-18.6 years, respectively. Mean age was statistically significantly (P < 0.05) lower among girls compared to boys for all third molar teeth (#18, #28, #38, and #48). The difference in mean eruption times between girls and boys was -0.62 (95% confidence interval: 0.2-1.0, P = 0.006). At 18 years, 40% or 41% maxillary and 52% or 53% mandibular molars were completely erupted. There were statistically significant differences in eruption between the sexes and jaws for all teeth (P < 0.05).

Conclusions: Given the fact that the percentage of erupted third molars by age 18 was found to be <50% on an average in this Ugandan population, we should reconsider the use of third molar eruption as a definitive tool for age estimation in this population.