Bonding of composite resins to PEEK: the influence of adhesive systems and air-abrasion parameters.

Abstract

The objective of the study was to investigate the tensile bond strength (TBS) to polyaryletheretherketone (PEEK) after different pretreatment and conditioning methods. Four hundred PEEK specimens were fabricated and allocated to the following air-abrasion methods (n 1=80/pretreatment): (i) 50μm Al2O3 (0.05MPa); (ii) 50μm Al2O3 (0.35MPa); (iii) 110μm Al2O3 (0.05MPa); (iv) 110μm Al2O3 (0.35MPa); and (v) Rocatec 110μm (0.28MPa). These pretreatments were combined with the following conditioning methods (n 2=20/pretreatment/conditioning): (a) visio.link (VL); (b) Monobond Plus/Heliobond (MH); (c) Scotchbond Universal (SU); and (d) dialog bonding fluid (DB). After veneering of all specimens with dialog occlusal and aging (28days H2O, 37°C+20,000 thermal cycles, 5/55°C), TBS was measured. Data was analysed using Kaplan-Meier survival analysis with Breslow-Gehan test and Cox-regressions. The major impact on TBS showed the conditioning, followed by the air-abrasion-pressure, while the grain size of the air-abrasion powder did not show any effect. Specimens air-abraded at 0.35MPa showed the highest survival rates. However, within VL groups, this observation was not statistically significant. Within MH groups, pretreatment using 110μm Al2O3 and 0.05MPa resulted in higher survival rates compared to groups treated with 50 and 110μm Al2O3 using a pressure of 0.35 MPa. The use of VL showed the highest survival rates between the adhesive systems and the TBS values higher than 25MPa independent of the pretreatment method. As an exception, only VL showed significantly higher survival rates when compared to MH. The adequate choice of the adhesive system and higher pressures improved the TBS between PEEK and veneering resin composite. The particle size had no major impact. According to this study, best veneering of PEEK with dialog occlusal can be achieved by conditioning with visio.link in combination with the pretreatment of airborne particle abrasion at a pressure of 0.35MPa.