A randomized sample of 1392 girls and boys, 16 to 20 years old and living in the canton of Geneva have been studied through their own history, clinically and radiologically in 1970-72 during an epidemiological and socio-economical study. The rate of alveolar bone resorption (radiographic method of Marshall-Day and Shourie, with Schei grid), the degree of gingival inflammation (PM index), the oral health (OHI-S index) and the carious frequency (DMFS index) have been determined. For the same sample, an indication of the duration of caries prevention through fluoride tablets, the frequency of daily toothbrushing and the dento-facial anomalies (Angle classes) were known. Through statistical analysis, it was shown that the mean rate of alveolar resorption was 0.85 (standard deviation 1,99) for the whole sample, that 24,16% of the subjects had a zero rate, 90% of the children having a rate of no more than 3,74 and that the maximum observed rate was 20. On the other hand, this bone resorption rate was statistically significantly correlated with the PM index and the OHI-S index. However no significant correlation has been shown between alveolar resorption and the other oral characteristics such as carious attack, toothbrushing, duration of caries prevention, dento-facial anomalies.