The relationship between the operational situation of dental treatment and accidents experienced was investigated through questionnaires sent to members of the Kagawa Dental Association. Responses were received from 261 dentists (53% response rate), of whom 113 (43%) had experienced accidents during dental examinations and/or treatment during the past one year. Dentists with a particularly high risk of having accidents were predominantly young males who possessed many medical chairs at their clinic and who daily examined many patients. Those dentists who worked together with two or more colleagues had a lower risk of accidents. These factors should be considered when trying to take preventive measures against accidents during medical examinations and treatment.