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Dental occlusion in a split Amazon indigenous population: genetics prevails over environment.
David Normando1, Jorge Faber, João Farias Guerreiro
1Department of Orthodontics, Dental School, Federal University of Pará, Belem, Brasil. davidnormando@hotmail.com
Plos One
|January 5, 2012
Summary
Genetics, not diet, significantly impacts dental malocclusion. This study on the Arara-Iriri people reveals genetic factors are the primary drivers of teeth misalignment, challenging previous hypotheses.
Area of Science:
- Anthropology
- Genetics
- Dental Science
Background:
- Dental malocclusion prevalence is increasing, with processed diets and reduced mastication hypothesized as causes.
- Previous research focused on primates; this study examines live human populations for genetic and tooth wear influences.
Purpose of the Study:
- To investigate the roles of genetics and tooth wear in dental malocclusion within a genetically cohesive indigenous population.
- To compare occlusal variation between two Arara-Iriri villages with differing genetic structures.
Main Methods:
- Evaluated dental malocclusion, tooth wear, and inbreeding coefficient (F) in 176 individuals from two Arara-Iriri villages.
- Utilized chi-square, Fisher's exact, and Mann-Whitney tests to analyze statistical differences.
- Confirmed high inbreeding in the resultant village through the inbreeding coefficient.
Main Results:
- Despite similar tooth wear, occlusal patterns differed significantly between villages.
- Dental malocclusion occurred in approximately one-third of the original village population, nearly doubling in the resultant village.
- Morphological characteristics of malocclusion varied substantially between the two groups.
Conclusions:
- Tooth wear has a limited influence on occlusal variation in living human populations.
- Genetic factors play a predominant role in the etiology of dental malocclusion.
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