Wear Resistance of Bulk-Fill Dental Resins Cured by Different Light-Curing Settings

Abstract

PurposeThe aim of this study was to investigate the wear behaviour of dental bulk-fill resins cured under different light-curing settings. Material and MethodsFour different materials investigated (Filtek, Beautifil, Admira, Powerfill) and cured with a light-curing unit at different curing settings and time. The wear loss of each material was investigated simulating 6- and 12-months wear in vivo, using a universal wear testing machine (UFW200) in a two-body dry wear with linear reciprocation design. Surface hardness also evaluated using nanoindentaion system. The worn surfaces were analysed under Scanning Electron Microscopy. Collected data was analysed statistically with one-way ANOVA and post hoc test. ResultsPowerfill resin showed the least wear loss (0.07 ± 0.03 mm), followed by Filtek specimens (0.09 ± 0.03 mm), whereas Beautifil resin showed the highest amount of wear loss (0.14 ± 0.05). The highest to lowest nanohardness in 3 s cured specimens were showed by Filtek, Powerfill, Admira, Beautifil (highest 0.66 ± 0.10 GPa, lowest 0.62 ± 0.16 GPa). SEM analysis suggested a wear mechanism of stress-induced cracking. ConclusionResin type has the most significant influence on wear behaviour. Increasing filler weight can negatively influence the wear resistance of bulk-fill resins. No correlation was found between wear resistance and surface hardness.