Effect of barium-containing glass filler reinforcement on shear bond strength of poly(ether ether ketone) to resin cement

Abstract

The purpose of this study was to evaluate how barium-containing glass filler (BGF) reinforcement and pretreatment methods affect shear bond strength (SBS) of poly(ether ether ketone) (PEEK) to resin cement. PEEK composites with various amounts of BGF (10, 20, 30 and 40 wt%) were prepared as PEEK-BGF10, PEEK-BGF20, PEEK-BGF30 and PEEK-BGF40. Afterward, PEEK and PEEK-BGF40 specimens were treated with hydrofluoric acid, sulfuric acid (H₂SO₄), silica coating and polishing, respectively. Acrylic hollow cylinders were luted with Dentex dual-curing resin cement to the specimens. Finally, SBS measurements were conducted with a universal testing machine. The introduction of BGFs greatly enhanced SBS of PEEK to resin cement. After simply polishing with 150 grit silicon carbide papers (G150), PEEK-BGF40 exhibited the SBS value up to 19.73 ± 4.30 MPa, similar to the PEEK treated with H₂SO₄ etching. Scanning electron microscopy and x-ray photoelectron spectroscopy were used to investigate the surface morphological and chemical changes in PEEK and PEEK-BGF composites before and after surface treatment. The results indicate that the introduction of BGF particles plays a key role in improving the adhesion between PEEK and resin cement. This study provides a new method to enhance the adhesion to PEEK without breaking its surface structure, which encourage further research in PEEK composite application in dentistry.