Localized Wear Simulation of Bulk-fil and Flowable Resin Composites

Objectives: The purpose of this study was to investigate simulated localized wear of flowable and low viscosity bulk-fill resin composites.
Methods: The flowable and low viscosity resin composites evaluated were : 1) Ever X Flow (EX) 2) Beautifil bulk (BB) 3) SDR flow +(SDR) 4) Bulk Base hard II high flow (BBH) 5) Bulk base hard II medium flow (BBM) 6) Bulk base hard II low flow (BBL) 7) Zero Flow (ZF) 8) Visalys Flow (VF) 9) Beautifil Unishade flow (BUF). Twelve specimens of each resin composite were prepared in custom stainless steel fixtures. The resin composite specimens (2400 grit surface) were subjected to 400,000 cycles in a Leinfelder-Suzuki (Alabama) wear simulator (maximum load of 78.5N) using a stainless steel ball bearing (r=2.39mm) for localized wear testing in a water slurry of PMMA beads. The specimens were profiled with a Proscan 2100 non-contact profilometer and wear [volume loss (VL) and maximum depth (MD)] was determined using ProScan software. A one-way ANOVA and Tukey's post hoc test were used for data analysis.
Results: ANOVA showed a significant difference among materials (p<0.001) for VL and MD. The post hoc tests revealed differences (p<0.05) in simulated localized wear (MD and VL) among the resin composites. The results for localized wear simulation were as follows: VL (mm³) – EX 0.062 (0.011), BB 0.083 (0.010), SDR 0.230 (0.020), BBH 0.245 (0.0222), BBM 0.258 (0.025), BBL 0.245 (0.029), ZF 0.042 (0.011), VF .032 (0.006), BUF 0.107 (0.008). MD (µm) – EX 120.7 (17.3), BB 113.2 (12.6), SDR 197.0 (21.2), BBH 238.6 (23.6), BBM 214.3 (21.5), BBL 216.9 (21.7), ZF 70.6 (11.1), VF 110.8 (21.3), BUF 98.6 (10.2).
Conclusions: Localized wear simulation demonstrated significant differences (p<0.05) in wear (facet depth and volume loss) among nine resin composite materials.