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Updated: Jun 14, 2025
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Published on: August 22, 2022
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Double Teeth and Coexistent Anomalies: Examples From Continental Africa
1Research Centre in Evolutionary Anthropology and Palaeoecology, School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, UK.
Summary
Double teeth, or gemination and fusion, are rare dental anomalies. This study found a low prevalence in African populations, suggesting unique developmental processes and potential shared etiologies with other dental anomalies.
Area of Science:
- Paleoanthropology
- Dental Morphology
- Human Evolution
Background:
- Double teeth (gemination or fusion) are rare worldwide, with limited data from Africa.
- Understanding their prevalence and associated anomalies in African populations is crucial for dental research.
Purpose of the Study:
- To document new cases of double teeth in African samples.
- To identify anomalies associated with double teeth.
- To estimate the prevalence of double teeth in North and sub-Saharan Africa.
Main Methods:
- Analysis of 97 modern and premodern African skeletal samples (5631 individuals).
- Recording presence of double teeth and coexistent anomalies.
- Prevalence estimation using a Poisson model for 95% confidence intervals (CI).
Main Results:
- Three cases of maxillary double teeth identified: primary incisor (Nubian), permanent incisor (Egyptian), and permanent incisor (Guinea).
- Associated anomalies include talon cusp, peg lateral incisor, premolar crown variation, and dens evaginatus.
- Prevalence varied regionally: 0.048% in premodern North Africa, 0.000% in modern North Africa, 0.000% in premodern sub-Saharan Africa, and 0.048% in modern sub-Saharan Africa.
Conclusions:
- African double incisors align with global developmental patterns of odontogenesis.
- Observed prevalence is lower than modern global rates, indicating potential exceptionality in African dental variants.
- Double teeth and associated anomalies may share common etiologies, warranting further research into their formation and expression.
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