Hyperdontia across sub-Saharan Africa: Prevalence, patterning, and implications.

OBJECTIVE

Hyperdontia data in modern and premodern sub-Saharan Africans are presented by region-West, Central, East, and South, and sex. Beyond describing the anomaly, comparisons are made with other world populations and future work is promoted. These findings may be useful to both dental clinicians and anthropologists.

METHODS

Hyperdontia presence and patterning were recorded in 51 samples of skeletal dentitions and hardstone casts (n = 1916). Its infrequency prompted regional pooling after grouping by time. Only adults were included to record later forming fourth molars reportedly common in Africans. Quantitative analyses, including 95% confidence intervals, were conducted to characterize spatiotemporally sub-Saharan peoples.

RESULTS

Forty-four of 1429 modern individuals (3.08%) exhibit hyperdontia (CI 2.24-4.13%). Regional variation is significant, particularly West-Central vs. East-South, between 6.8% and 1.5%. Four of 487 premodern individuals, 0.82%, have hyperdontia (0.22-2.10%), with minimal regional differences. Males are most affected, as reported by other researchers. Other similarities with non-African research are evident regarding isomere, antimere, and form, with one key exception-a proclivity for the posterior over anterior maxilla.

CONCLUSIONS

3.08% is toward the upper end of published world ranges, including an oft-cited 0.1-3.6 + %. However, the regional variation argues against a single prevalence to describe collectively the subcontinental inhabitants. This variation parallels past west to east and south migrations like other biocultural indicators. Thus, beyond a health concern to clinicians or interesting anomaly to anthropologists, hyperdontia may be useful in other studies. There are no equivalent premodern ranges for comparison. Similarity in patterning overall to previous findings suggests a shared, potentially ancient genetic component in expression.