Fatigue Behavior of Multi/Unit-Supported Dental Restorations: Implant Platform vs. Prosthetic Platform.

The increasing popularity of Multi/Unit abutments in dental restorations is attributed to their clinical advantages, yet little is known about their mechanical behavior, particularly in terms of fatigue performance. This study aimed to evaluate the mechanical behavior of Multi/Unit abutments with a focus on the impact of implant and prosthetic platform diameters on fatigue performance. Five dental restoration models were analyzed using Finite Element Analysis by incorporating implants of identical length and body diameter but varying implant platform size (3.5 and 4.1 mm) and prosthetic platform size (3.5, 4.1, and 5.5 mm). Mechanical stresses on critical sections of the screws were assessed under cyclic loads. The results revealed that the implant platform diameter had minimal influence on the fatigue performance of the prosthetic screw, while a wider prosthetic platform significantly improved its mechanical behavior by reducing stress and allowing the use of larger screw metrics. These findings emphasize that the prosthetic platform diameter plays a crucial role in protecting the prosthetic screw, which is often the critical component in dental restorations that use Multi/Unit abutments. The study highlights the importance of carefully selecting platform dimensions to optimize the mechanical performance and longevity of dental restorations utilizing Multi/Unit abutments.