Effect of Various Treatment Modalities on Surface Characteristics and Shear Bond Strengths of Polyetheretherketone-Based Core Materials Ahmet K ¨ urs ¸ at C ¸ ulhao ˘ glu, DDS, PhD, 1 Serhat Emre ¨ Ozkır, DDS, PhD, 2 Volkan S ¸ ahin, DDS, PhD, 1 Burak Yılmaz, DDS, PhD, 3 & Mehmet Ali Kılıc ¸ arslan, DDS, PhD 4 1 Faculty of Dentistry, Department of Prosthodontics, Kırıkkale University, Kırıkkale, Turkey 2 Department of Prosthodontics, Afyon Kocatepe University School of Dentistry, Afyonkarahisar, Turkey 3 Department of Restorative Dentistry and Prosthodontics, The Ohio State University College of Dentistry, Columbus, OH 4 Faculty of Dentistry, Department of Prosthodontics, Ankara University, Ankara, Turkey Keywords Laser; PEEK; shear bond strength. Correspondence Volkan S ¸ ahin, Department of Prosthodontics, Faculty of Dentistry, Kırıkkale University, C ¸ elebi Sokak No:1 Yahs ¸ ihan, Kırıkkale 71451, Turkey. E-mail: vlknshn@yahoo.com. The authors deny any conflicts of interest related to this study. Accepted July 8, 2017 doi: 10.1111/jopr.12702 Abstract Purpose: To investigate the effect of different surface treatments on the surface roughness (Ra), wettability, and shear bond strength of polyetheretherketone (PEEK) to composite resin. Materials and Methods: One hundred ninety eight PEEK specimens were divided into six groups (n = 33). Specimen surfaces were treated with the following surface treatment modalities: silicoating (CoJet), acetone treatment, acid etching (H 2 SO 4 ), airborne particle abrasion (Al 2 O 3 ), laser irradiation (Yb:PL laser), and the nontreated surface serving as the control. Surface roughness was measured with an profilometer (n = 11) and a goniometer was used to measure the surface wettability through contact angle (θ )(n = 11). PEEK surfaces were veneered with a composite resin (n = 11). The specimens were then thermocycled for 10,000 cycles at 5 to 55°C. Shear bond strengths between the PEEK and composite resin were measured with an universal test machine. One-way ANOVA was used to analyze the data. Tukey’s post-hoc test was used to determine significant differences between groups (α = 0.05). Results: Surface roughness and wettability of PEEK surfaces along with shear bond strength of PEEK to composite resin were influenced by the surface treatments. (p < 0.01) Highest mean Ra values were obtained for PEEK sur- faces treated by laser irradiation (2.85 ± 0.2 µm) followed by airborne parti- cle abrasion (2.26 ± 0.33 µm), whereas other surface treatment modalities pro- vided similar Ra values, with the acid-etched PEEK surfaces having the low- est mean Ra values (0.35 ± 0.14 µm). Silicoating provided the most wettable PEEK surfaces (48.04 ± 6.28º), followed by either acetone treatment (70.19 ± 4.49º) or acid treatment (76.07 ± 6.61º). Decreased wettability was observed for airborne particle abraded (84.83 ± 4.56º) and laser-treated PEEK surfaces (103.06 ± 4.88º). The highest mean shear bond strength values were observed for acid-etched PEEK surfaces (15.82 ± 4.23 MPa) followed by laser irradiated (11.46 ± 1.97 MPa), airborne particle abraded (10.81 ± 3.06 MPa), and silicoated PEEK surfaces (8.07 ± 2.54 MPa). Acetone-treated (5.98 ± 1.54 MPa) and untreated PEEK surfaces (5.09 ± 2.14 MPa) provided the lowest mean shear bond strengths. Conclusions: The highest mean shear bond strengths were observed for acid- etched PEEK surfaces, followed by laser-irradiated, airborne particle abraded, and silicoated PEEK surfaces providing similar mean shear bond strengths. Since shear bond strengths higher than 10 MPa are considered acceptable, acid etching, laser irradiation, and airborne particle abrasion of PEEK surfaces may be considered viable surface treatment modalities for the PEEK material tested. Improvements in computer-aided design/computer-aided man- ufacturing (CAD/CAM) technology have enabled the use of both ceramic and resin-based materials for dental restora- tions. High-density resin-based CAM blanks have improved properties such as higher fracture resistance, better stress distri- bution, and lower abrasion of the opposing dentition compared to conventional resin polymers. These properties make them an alternative material to glass ceramics. 1-4 1 Journal of Prosthodontics 00 (2017) 1–6 C  2017 by the American College of Prosthodontists