Objective: To evaluate the role of genetics and tooth wear in the etiology of dental crowding through the analysis of a split indigenous Amazon population.
Materials and methods: Dental crowding prevalence (n = 117), tooth wear (n = 117), and inbreeding coefficient (n = 288) were compared for both villages. A biometric investigation was performed by dental cast analysis of 55 individuals with no tooth loss. Mann-Whitney statistics, independent t-tests, and Fisher exact tests were used at P < .05.
Results: A high coefficient of inbreeding was confirmed in the resultant village (F = 0.25, P < .001). Tooth wear was not significantly different (P = .99), while a significantly higher prevalence of dental crowding was confirmed in the original village (PR = 6.67, P = 0.02). Forty dental arches (n = 20) were examined in the new group, and only one (2.5%) had a dental crowding ≥ 5 mm. In the original villages, we found 20 arches (28.6%) with dental crowding. No difference was observed for tooth size, while larger dental arch dimensions explained a lower level of dental crowding in the resultant village.
Conclusions: Our findings downplay the widespread influence of tooth wear, a direct evidence of what an individual ate in the past, on dental crowding and emphasize the role of heredity, exacerbated through inbreeding, in the etiology of this malocclusion.