Developments in medical science have led to an increase in human life expectancy and allow for the management and treatment of systemic conditions which in the past had a low survival rate. The technical development of biomaterials and electro-medical instruments, changing lifestyles and of morbidity leads to a broadening of the class of so-called patients "at risk." Dentists need a more careful analysis of the clinical risks involved; the approach should be firstly medical and then dental. The dentist must consider both technological and medical-legal aspects, sticking with the principle of risk versus benefit, and not exclude postponing dental treatments if indicated. The main safeguard for the patient at risk is a more extensive anamnesis, combined with a complete observation to identify or recognize conditions that are potentially hazardous. The author offers some reflections on the conduct to be adopted to cure safely, but also to avoid any judicial proceeding. Profiles of professional liability may, in fact, result from failing to follow care guidelines for that particular state of the clinical risk. However, the private nature of dental care and the code of medical ethics also allow the clinician the choice of not treating the patient if it is believed that the clinical risk and any medical emergency could not be dealt properly, or that oral health pathologies may require a more complex medical structure with the simultaneous presence of other specialists.