The Precautionary Principle in Dentistry

Abstract

The public does not expect serious side effects when visiting the dentist. And, by and large, the dental profession has succeeded in providing reasonable assurances that serious side effects associated with dental treatments are rare. However they do occur and absolute safety cannot be guaranteed. Even simple and routine dental procedures such as the administration of local anesthetics in dentistry can result in adverse events. Bone or blood products used in periodontal surgery may be contaminated with bloodborne diseases, patients on bisphosphates may develop osteonecrosis of the jaw as a result of surgical procedure, inferior alveolar nerves may get severed with implants or wisdom tooth extractions, and cancers may get induced by computed tomography scans. One can approach such risks from a precautionary or a risk-based perspective. A precautionary approach would consider alternative treatments with lower risks, or inform patients about potential risks even when the risks may only be theoretical and when no credible evidence exists to suggest harm. A risk-based approach, on the contrary, would forego such precautions until credible evidence exists that a procedure or treatment is associated with adverse events. Consider a patient on oral bisphosphonates presenting to your dental practice for dental extractions and implants. The concern is osteonecrosis of the jawVa condition where the jaw necroses. No effective treatment to control this condition exists. The evidence that oral bisphosphonates are associated with this condition is weak. While suggestive evidence on dose-response exists, and while the temporality of the events and the biological plausibility provide suggestions of causality, the evidence is weak. No well-designed case-control studies have established the presence of a causal association. Two contrasting clinical approaches are possible. A precautionary approach would be to provide patients with an informed consent describing in detail the potential risks, to avoid dental surgery, and, if possible, to do a dental clean-up prior to start of bisphosphonates therapy. Such an approach is practiced by some oral and maxillofacial surgeons who provide a detailed informed consent on the risks of bisphosphonates. A risk-based approach would be usual care (no informed consent, no changes in clinical practice). The argument for a risk-based approach would be that the precautionary approach increases cost of care unnecessarily, may cause unnecessary anxiety, and a paralysis of care. A dental practice based on the precautionary principle and the risk-based principle are quite distinct. Three speakers were invited to provide their perspectives on the precautionary principle and their presentations are summarized in the 3 ensuing reports.