ürkiye Klinikleri Diş Hekimliği Bilimleri Dergisi, cilt.16, ss.122-130, 2010 (Diğer Kurumların Hakemli Dergileri)
Objective: In removable partial prosthetics, distributing masticatory loads evenly along the abutment teeth and supportive mucosa is related to the design of direct retainers. Design of clasps as direct retainers, plays a major role in the preservation of the abutment teeth. The purpose of this study is to evaluate the effect of occlusal rest localization on the stress distribution over supporting tissues by finite element analysis. Material and Methods: A bilateral distal extension removable partial denture supported by cast akers and modified back-action clasps on mandibular first premolars was modelled. A 100-N load simulating the masticatory forces was applied to the denture in the z axis direction. σ? stress ditributions over the supporting tissues generated by different localization of occlusal rests along the x-x axis were evaluated. Results: The highest stress concentrations were located on the alveoler bone and metal framework of the denture. The rest of the stress were concentrated on the teeth and periodontal tissues. In the mesially localised occlusal rest model, masticatory forces distributed to the supporting tissues were lower. On the other hand, on the distally localised occlusal rest model, detrimental masticatory tensile forces occurred over the supporting tissues. Conclusion: In the distal extension removable partial dentures, mesially localised occlusal rests showed more favorable stress distributions over the abutment teeth.