Dentists’ Legal Liability and Duty of Explanation in Dental Malpractice Litigation in Japan

INTRODUCTION: Dental litigation accounts for approximately 10% of medical cases in Japan. This study sought to identify factors related to dentists’ legal liability in Japan, including their duty to explain procedures and treatments to their patients. METHODS: We analysed court decisions in 166 dental malpractice cases litigated in Japan between 1978 and 2017. To identify factors related to the legal liability of dentists, an analysis was performed to evaluate the associations among patient characteristics, dentist characteristics, litigation, and dentists’ explanatory behaviour. RESULTS: Of the 36 cases related to dentist liability, the study identified 23 cases (63.9%) of litigation in which the dentists were found to be in violation of their duty to provide an explanation. Regarding the severity of injury, the ratio of death and permanent disability was significantly higher in decisions in which the purpose of the explanation was something other than obtaining the patient's consent compared with decisions to obtain the patient's consent (P = .014). CONCLUSIONS: In cases in which the dentist was found legally responsible, the proportion of cases involving procedural negligence with the explanation of medical guidance was significantly higher. Dentists should pay careful attention not only to the patient's consent but also to their explanations, including “medical guidance.” Moreover, they should recognise that inappropriate explanations correlate with serious errors.