Third molar agenesis varied strongly between South African population groups

What the study found: Third molar agenesis, meaning the absence of one or more wisdom teeth, differed greatly between the two South African population groups studied. It was much more common in White South Africans than in Black South Africans.

Why the authors say this matters: The authors conclude that sole reliance on third molar assessment for dental age estimation may lead to inaccurate age estimates, especially in multi-ethnic populations. They say population-specific reference data are essential to improve the accuracy and reliability of forensic dental age estimation.

What the researchers tested: The researchers carried out a retrospective analysis of orthopantomograms, which are panoramic dental X-rays, from 2,536 individuals: 1,688 Black South Africans and 848 White South Africans. They assessed third molar agenesis by tooth position, sex, population group, and birth cohort.

What worked and what didn't: Third molar agenesis was significantly more prevalent in White South Africans (28.42%) than in Black South Africans (6.81%). The overall prevalence of at least one missing third molar was 14.92% in males and 13.33% in females, and agenesis occurred slightly more often in the maxillary arch, meaning the upper jaw, than in the mandibular arch, meaning the lower jaw. There were no consistent sex-related or side-related differences, and prevalence declined over time across birth cohorts.

What to keep in mind: The abstract does not describe detailed study limitations. The findings are based on the studied South African sample and on third molar development as assessed from orthopantomograms.

Key points

• Third molar agenesis was much more common in White South Africans than in Black South Africans.
• The study examined 2,536 people using panoramic dental X-rays.
• At least one missing third molar was found in 14.92% of males and 13.33% of females.
• Agenesis was slightly more frequent in the upper jaw than in the lower jaw.
• The authors say population-specific reference data are needed for dental age estimation.