Evaluation of 1-Piece Versus 3-Piece Framework Designs for the Edentulous Mandible with Fixed Implant-Supported Prostheses: A Clinical, Occlusal and Biomechanical Study.

Purpose: This study aims to evaluate the clinical, occlusal and biomechanical performance of 1-piece and 3-piece designs for implant-supported fixed dentures in the edentulous mandible.

Materials And Methods: A total of 65 patients with edentulous mandibles who underwent fixed implant-supported restorations were recruited and subsequently assigned to 1 of 2 groups based on the framework design (1-piece or 3-piece). The participants underwent clinical and occlusal examination using a periodontal probe, T-Scan III system, and electromyography 12 months after prosthesis delivery. Two mandibular finite element models were created to evaluate stress values and their distribution during function.

Results: Ninety-five point four percent (n = 62) of participants in the follow-up period underwent clinical and occlusal examination after prosthesis delivery. Clinical examination revealed a trend towards increased inflammation around the implants in the 1-piece prostheses. Occlusal parameters indicated that the 1-piece design was superior for the masticatory system than the 3-piece design. Biomechanical analysis revealed the highest stress values in the posterior region of the 3-piece design.

Conclusions: On the basis of ease of ensuring oral hygiene, when compared to the 3-piece design, the 1-piece framework design might be the superior therapy for restoring an edentulous mandible, based on occlusal and biomechanical outcomes.