During the last few years in Sweden, there has been a change in the way of living for the mentally retarded. There has been a gradual movement away from institutions toward a more integrated life within society. The aim of the present study was to examine the dental health of mentally retarded adults with different ways of living. Forty-two subjects lived in an institution, 50 lived in integrated units, and 40 stayed in their own apartments or with their parents. All subjects had had regular dental care for at least ten years. The clinical examination was made by one dentist. The use of fluoride and chlorhexidine was recorded in addition to a microbiological examination. The results showed a higher caries prevalence and incidence in subjects with integrated living. Compared with other studies where the mentally retarded had had no regular dental care, the caries incidence and prevalence were lower in this study, and the number of missing teeth was lower. The prevalence of mutans streptococci was related to caries prevalence and incidence. High scores of mutans streptococci could be observed, even among subjects with a frequent use of chlorhexidine gel. The loss of alveolar bone was more pronounced for individuals living in the institution compared with that in individuals with other ways of living.