Flexural strength, surface roughness, and biofilm formation of ceramic-reinforced PEEK: An in vitro comparative study.

Abstract

This in vitro study aimed to compare flexural strength, surface roughness, and biofilm formation of ceramic-reinforced PEEK with conventionally heat-compressed and milled polymethylmethacrylate (PMMA) denture base materials. Thirty strips (6.4×10×3 mm) and 30 discs (10×1 mm) were fabricated from a heat-compressed PMMA, milled PMMA, and ceramic-reinforced PEEK, 10 each. One surface of each sample was polished to mimic the laboratory procedure for denture base materials. Strips were then subjected to a 3-point bend test using a universal testing machine at a crosshead speed of 5.0 mm/min. An optical profilometer was used to assess the Ra value (mm) of the discs on polished and unpolished sides. Biofilm formation behavior was analyzed by measuring the colony-forming unit (CFU)/ml of Candida albicans on the unpolished surface of the discs. One-way ANOVA followed by Tukey multiple comparison tests were used to compare the flexural strength, Ra value, and biofilm formation of the studied materials (a = 0.05). Ceramic-reinforced PEEK showed significantly higher flexural strength (178.2 ±3.2 MPa) than milled PMMA (89.6 ±0.8 MPa; P<0.001) and heat-compressed PMMA (67.3 ±5.3 MPa; P<0.001). Ceramic-reinforced PEEK exhibited a significantly higher Ra value than the other groups on unpolished sides; however, the polishing process significantly reduced the Ra values of all studied groups (P<0.05). There was no significant difference in Candida albicans adhesion among the groups (P<0.05). The flexural strength of tested materials was within acceptable limits for clinical use as a denture base material. Ceramic-reinforced PEEK had the highest surface roughness; however, its similarity in biofilm formation to other groups indicates its clinical acceptability as denture base material. This article is protected by copyright. All rights reserved.