Measuring periodontal disease in ancient populations: root and wear indices in study of American Indian skulls.

As an example of the collaboration of periodontologists and physical anthropologists, the skulls of two Indian populations were studied. A root index to assay periodontal disease and a wear index to evaluate occlusal wear, were developed. The first Indian population, living 400 years ago, had more decay, loss of teeth and caries; the second population, living 4,000 years ago, exhibited more periodontal disease. Starting with a sample of eight teeth, two from each quadrant, the statistical analysis showed that a smaller number of teeth would give a reliable assessment of past oral health. Based on our findings, the canines proved to be good indicators for general wear and the incisors for periodontal disease. A six-tooth index of varying teeth studied is proposed for the root index and the wear index in future studies of oral health of ancient populations.