Comparative evaluation of BioHPP and titanium as a framework veneered with composite resin for implant-supported fixed dental prostheses

Abstract

Statement of problem: High rates of veneering chipping are a common prosthodontic complication of restorations with a titanium framework. A new bio high-performance polymer (BioHPP) based on polyetheretherketone (PEEK) has been introduced for denture superstructures. Clinical reports suggest that BioHPP could be used as an alternative framework material to support complete-arch restorations. However, peer-reviewed information is lacking regarding the performance of BioHPP as a framework material for implant-supported screw-retained fixed dental prostheses (FDPs) veneered with composite resin.

Purpose: The purpose of this in vitro study was to evaluate and compare the bond strength of modified PEEK (BioHHP) and titanium with a veneering composite resin and compare the marginal fit and fracture resistance of implant-supported screw-retained FDPs fabricated by using computer-aided design and computer-aided manufacturing (CAD-CAM) frameworks veneered with composite resin.

Material and methods: A composite resin was bonded to 2 framework materials (n=20/group): pure titanium (Ti) and BioHPP (Bi). The shear bond strength (SBS) was determined after 24-hour wet storage. Furthermore, 20 3-unit CAD-CAM BioHPP and titanium frameworks were fabricated (n=10/group). The marginal fit between frameworks and abutments was evaluated by scanning electron microscopy by using the single-screw test. After thermocycling and mastication simulation, the fracture resistance of FDPs veneered with the composite resin was examined. The independent sample t test was used to evaluate differences (α=.05).

Results: Significantly higher shear bond strengths were obtained in group Bi (31.1 ±3.5 MPa) than in group Ti (20.5 ±1.8 MPa). The mean marginal gap width was 19 ±4 μm in group Bi and 16 ±6 μm in group Ti. Statistical tests showed no significant differences (P>.05). After loading, veneering chipping was observed at a load of 1960 ±233 N in group Ti. Although the BioHPP frameworks fractured at 1518 ±134 N, no chipping occurred.

Conclusions: The bond strength of BioHPP with the composite resin was greater than that of titanium. CAD-CAM BioHPP frameworks exhibit good marginal fit and fracture resistance. BioHPP may be a suitable alternative to metal as a framework to be veneered with composite resin.