Sapporo Medical Journal

Abstract : Introduction: Occlusal overloading compromises dental implant durability but using thermoplastic materials for bars in implant-supported overdentures is an effective solution to this problem. Aim: Evaluate the impact of using Polyetherketoneketone (PEKK) and Bio High-Performance Polymer (BioHPP) CAD/CAM materials on stress distribution around implants in bar-retained implant-supported prostheses. Materials and methods: A mandibular 3D-printed cast model from epoxy resin was used for this study, with selected implant sites surrounded by channels to allow a 2mm resin thickness between strain gauge rosettes and the implant. Two implants were inserted parallel to their sites in the model, and Ti-base abutments were screwed in. The impression was digitally scanned, and dental bars were designed. Eight identical bars (n=4) (four BioHPP and four PEKK) were milled using CAD/CAM. Strain gauges measured micro-strain around the implants, and stress analysis was conducted using a universal testing machine. Results were collected, tabulated, and analyzed with statistical software. Results: BioHPP milled bars have shown less force-transmitted and less traumatic effects on the implant and supporting structures. conclusion BioHPP CAD-CAM Materials can be used as Bar-Retained Implant-Supported Prostheses