Evaluation of enamel wear by 3 occlusal splint materials: An in vitro study

Abstract

Statement of problem: Occlusal devices used to manage bruxism have been commonly fabricated from polymethyl methacrylate with the powder-liquid technique. More recently, Vertex ThermoSens (VTS) and the biocompatible high-performance polymer (BioHPP), an optimized material having polyetheretherketone (PEEK) as its basis, have been used, but little is known about the wear of these materials on human enamel.

Purpose: The purpose of this in vitro study was to assess via a mastication simulation test how 3 occlusal device materials affected the wear and roughness of enamel antagonists.

Material and methods: A noncontact 3D optical profilometer was used to measure the enamel surface roughness (Ra) against 3 occlusal device materials: vertex regular, VTS, and PEEK high-performance polymer (BioHPP). A dual-axis mastication simulator was used to perform a 2-body wear test on specimens from each group. The test consisted of 10 000 cycles with a 70-N force and 5 to 55 °C thermocycling. Following simulated mastication, the weight of each specimen and the Ra change were compared with the Kolmogorov-Smirnov test, paired specimens t test, Wilcoxon signed-rank test, and 1-way analysis of variance (α=.05).

Results: The polyamide group caused the lowest amount of enamel wear (P<.05), while the heat-polymerized acrylic resin group induced the largest amount of enamel wear (P<.05). For polyamide and PEEK, the change in enamel surface roughness exhibited a smooth texture, whereas it found a rougher surface for the heat-polymerized acrylic resin.

Conclusions: According to this study, surface roughness and wear on human enamel were not correlated. PEEK is a promising material for the fabrication of occlusal devices.