To clarify the relationship between daily performed dental practices and work-related physical complaints by dentists, we examined 16 male dentists who worked at their clinic in an urban district. Each subject answered a questionnaire concerning work-related complaints and was examined by a time study of daily actions. The electromyograms of back muscles were taken from ten different positions. Approximately 62% of the daily practice was occupied by the dental care work. The dental care postures were classified into 3 types according to the inclination of the body. The most common posture was a right-forward position. The prevalence of complaints including problems with eyes, hands and arms, neck and shoulders and low back differed among 3 types. The order of complaints was neck and shoulders, eyes, and low back. The amplitude of the electromyograms was increased by the extension of the muscles to lateral bending of 30°and internal rotation of 15°. These results suggest that the body positions of daily dental care practices cause an increase in work-related complaints in dentists.