Repair of resin-veneered polyetheretherketone after veneer fracture

Statement of problem: If a composite resin-veneered polyetheretherketone (PEEK) restoration chips or fractures, a repair may be indicated. However, the most appropriate repair protocol for a composite resin-veneered PEEK restoration is unclear. Purpose: The purpose of this in vitro study was to determine the efficacy of airborne-particle abrasion and/or a primer in the repair of composite resin-veneered PEEK prostheses. Material and methods: PEEK specimens (N=80) were airborne-particle abraded with alumina before being conditioned with a methyl methacrylate-based primer. A thin layer of opaquer was applied, and a split mold was then filled with a veneering resin. The specimens underwent 5000 thermocycles, and then shear bond strength (SBS) was determined and used as the positive control group. Specimens that failed in either mixed or adhesive modes were contaminated with saliva and then exposed to 4 different repair treatment methods: no airborne-particle abrasion, bonded without a primer (negative control group); airborne-particle abrasion, bonded without a primer; no airborne-particle abrasion, bonded with a primer; and airborne-particle abrasion, bonded with a primer. All specimens had opaquer applied before being veneered. Repaired specimens then underwent thermocycling before SBS testing. Data were analyzed via ANOVA with a Newman-Keuls post hoc test (α=.05). Results: The SBS values for the negative control were significantly lower than those of all other repair groups and the control group (P<.018). No significant differences in the SBS values were found among these other repair groups or the positive control group (P>.05). Conclusions: Composite resin-veneered PEEK restorations or prostheses repaired with airborne-particle abrasion and/or primer can provide SBS comparable with that of the initial SBS.