Shear bond strength of different luting agents to polyether ether ketone

Background: Polyether ether ketone (PEEK) was recently introduced to dentistry. However, difficulty in provision of a strong durable bond is its main drawback. Thus, precise surface treatment and use of a suitable luting agent are imperative for bonding of PEEK restorations. This study aimed to assess the effect of type of luting agent on shear bond strength (SBS) of PEEK. Materials and Methods: In this in vitro study, 60 square-shaped PEEK samples were fabricated and sandblasted with 110 μm Al2O3 particles. The samples were then divided into four groups based on the type of cement used (n = 15): zinc phosphate cement, Panavia F2, Panavia V5, and resin-modified glass-ionomer (RMGI) cement. After bonding, the samples were thermocycled for 5000 cycles. The SBS was measured by a universal testing machine. The surface of samples was inspected under a video measuring machine to determine the mode of failure. Data were analyzed using the Kruskal–Wallis test via SPSS version 24 (α = 0.05). Results: RMGI did not bond to PEEK. The SBS values were 4.02 ± 2.87 megapascals (MPa) for Panavia V5, 10.84 ± 6.05 MPa for Panavia F2, and 10.50 ± 2.88 MPa for zinc phosphate. The SBS in the Panavia V5 group was significantly lower than that in the Panavia F2 (P = 0.001) and zinc phosphate (P < 0.001) groups. No significant difference existed between the Panavia F2 and zinc phosphate groups in this respect (P > 0.05). Conclusion: Panavia F2 resin cement and zinc phosphate conventional cement provided the highest bond strength to PEEK, while RMGI did not bond to PEEK.