Biteforce and Chewing Efficiency of CAD/CAM PEEK Versus PMMA Implant-Overdenture

Objectives: The purpose of this study was to compare between two types of CAD/CAM denture bases; acrylic resin (PMMA) denture base and Poly Ether Ether Ketone (PEEK) denture base for mandibular implant overdenture in terms of bite force and chewing efficiency.
Methods: Twelve completely edentulous patients with persistent complaint of poor retention and stability of their mandibular complete dentures were selected. Each participant received two mandibular intra-foraminal implants in the canine region, then patients were classified into 2 groups. Group I: received CAD/CAM PEEK mandibular overdenture (OD), Group II: received CAD/CAM PMMA mandibular overdenture. Chewing efficiency of both groups in terms of measuring the unmixed chewing gum fraction (UF) was assessed using two-colour mixing ability test. Biting force was also assessed using bite force transducer. Assessments were carried out after insertion then three months and six months after overdenture insertion. Results were statically analyzed, ANOVA (P<.05).
Results: Regarding chewing efficiency CAD/CAM PMMA overdenture recorded significantly higher UF than CAD/CAM PEEK overdenture for all observations. The highest UF was observed with T0 (p <.001), followed by T3 (p <.001), and the lowest UF was noted with T6 (p <.001). Regarding bite force there was a significant difference between groups (p<.001), for all observations CAD/CAM PEEK OD recorded significantly higher bite force MBF than CAD/CAM PMMA OD T0(p <.001), T3 (p <.001) and T6 (p <.001).
Conclusions: Within the limitations of this study, it can be concluded that restoring the edentulous mandible with CAD/CAM PEEK prefabricated implant overdenture improves the masticatory efficiency and maximum biting force compared to CAD/CAM PMMA overdenture.