[Prevalence of Streptococcus mutans in pehuenche children, Chilean ethnic group].

We studied 26 pehuenche children between 9 and 13 years of age and 12 non-pehuenche controls. Samples were obtained from saliva and from the bacterial plaque of 6 year molars and cultured anaerobically for 48 hr at 37 C in TYCSB medium. S mutans were obtained from 90% of children in both groups, all corresponding to biotype I (Coykendall). Nutritional and hygienic habits did not differ between groups. These results confirm the ample distribution of S mutants in Chilean subjects.