Despite high survival percentages of oral implants and suprastructures, various risks threaten the success of oral implant treatments. Four risk categories can be distinguished: complications during surgical treatment, loss or impending loss of the implant, fracture or wearing out of (parts of) the suprastructure, and patient dissatisfaction with the treatment outcome. The question is when a complication can be expected on the basis of present-day knowledge in a certain percentage of cases and when one can speak of negligence. In cases where treatment is carried out in accordance with the most recent protocols, guidelines and recommendations, there can be no question of liability. It is proposed that retreatment is carried out without any costs if an implant or a superstructure is lost within one year post-treatment.