Short-term comparative evaluation of BioHPP and cast cobalt–chromium as framework for implant supported prostheses: A split mouth clinical randomized trial

Abstract

Aim: The purpose of this parallel randomized clinical trial was to evaluate the effects of BioHPP versus cobalt–chromium (Co–Cr) frameworks in screw-retained implant-supported fixed dental prostheses (FDPs) on peri-implant soft and hard tissues clinically and radiographically. Materials and Methods: Fifteen patients with bilateral partial edentulism in the posterior mandible received two implants at the positions of the second premolar and second molar on both sides: one side was restored with BioHpp-based screw-retained FDP (test group) and the other side was restored with Co–Cr-based screw-retained FDP (control group). All patients were clinically examined at the time of prosthesis insertion, and 6 and 12 months later for fracture of implant or framework, fracture, or looseness of the screw, veneer chipping, and fractures, modified bleeding index, modified plaque index, peri-implant probing depth, as well as radiographically for marginal bone loss. Results: At 12 months, both groups showed no statistically significant differences in the modified bleeding index (P = 1.00), modified plaque index (P = 0.383), probing depth (P = 0.925), and marginal bone loss (P = 0.222). No technical complications occurred during the evaluation period in either group. Conclusion: BioHPP framework represents a viable nonmetallic alternative to cast Co–Cr framework, shown by good soft and hard tissue responses.