Three-body wear of luting composites and influence of the ACTA wheel material.

The aim of the study was to investigate the wear of luting materials (Variolink Esthetic LC/DC, Multilink Automix, Panavia V5 paste) compared to a resin composite (Tetric EvoFlow) with an ACTA-machine (three-body-wear simulator) using steel and 3D-printed polymer wheels. Wear was measured (software Match3D) and statistically analyzed (ANOVA). Worn surface was examined with a field-emission-scanning-electron-microscope. Finite element analysis was carried out to analyze differences in the mechanical stress of the two different sample wheels. Using the steel wheel, Variolink Esthetic DC exhibited significantly less wear than Tetric EvoFlow after 200,000 cycles (p=0.037). Luting composites on polymer wheels exhibited significantly lower wear values compared to the steel wheels (p<0.001). Finite element analysis showed higher stresses for the steel wheel compared to the polymer wheel. Mechanical properties of the sample wheels had a high influence on wear properties. Dual- or auto-polymerizing materials seem to have a small advantage over the light-curing materials.