What is a common reason for failure of partial FDP interim restorations?

A common reason for the failure of partial removable denture interim restorations is excessive stress on the connectors. When the connectors, which serve as the framework that holds the prosthesis together, are subjected to forces that exceed their tensile strength, they can become fractured or deformed. This is particularly important in interim restorations, which are designed to be temporary and may not have the same structural integrity as permanent restorations. Excessive forces can arise from improper occlusion, parafunctional habits, or inadequate support from the remaining natural dentition.

Understanding the importance of connectors allows dental practitioners to design interim restorations that distribute occlusal forces more evenly and minimize the risk of stress-related failures. This involves careful consideration of the materials used as well as the patient's bite relationship to ensure the interim restoration functions effectively until a more permanent solution is placed.