• oral lesions;
  • epidemiology;
  • focal epithelial hyperplasia;
  • fissured tongue

Background:  A cross-sectional study on the oral mucosal conditions among the Waimiri Atroari Indians from central Amazonia, Brazil, has been conducted. These Indians keep their traditional way of life and are free from habits such as smoking, alcohol drinking, and use of pacifiers.

Methods:  Clinical examinations of a representative, randomly selected sample of patients during routine dental treatment, following ethical procedures recommended by Brazilian laws were made.

Results:  Out of 922 individuals, 587 were examined, among which 52.57% of the children up to 12 years old and 73.44% of patients aged 13 years or older presented at least one oral mucosal condition. The conditions more frequently observed were, in decreasing order of prevalence: fissured tongue, focal epithelial hyperplasia (FEH), lesions of traumatic origin, geographic tongue, Fordyce's spots, and candidiasis. Only one case of leukoplakia was identified.

Conclusions:  Conditions observed among theses Indians were essentially the same that have been described in other populations around the world, except for FEH, which, as a characteristic lesion of Indians, had high prevalence (20.95%). The lesions observed were related to the way of life of this specific population.