Effect of routine scaling and prophylactic polishing on the surface roughness of nano-filled restorative materials: In vitro study

Abstract

AimThis study aimed at investigating in vitro the effect of routine scaling (hand/ultrasonic) and polishing on the surface roughness of three nano-filled restorative materials. Materials and methodsNano-filled universal resin composite (Filtek Z350), nano-filled flowable resin campsite (Filtek Supreme Plus Flow) and resin modified glass ionomer (Ketac N100) were tested. Ninety discs (10 mm × 2 mm) were prepared and divided into 3 groups (n = 30/material). Each group was divided into 5 subgroups (n = 6). Subgroup 1: control (surface against matrix), subgroup 2: ultrasonically scaled (US), subgroup 3: hand scaled, subgroups 4 and 5 were US, hand scaled then received prophylactic polishing respectively. The mean surface roughness (Ra μm) of all specimens was measured by a profilometer. Data were statistically analyzed by ANOVA and post-hoc tests (P ≤ 0.05). Representative specimens were examined by the SEM. ResultsUnder all testing conditions, Ketac N showed the highest mean Ra value expect for hand scaled/non-polished specimens, where they were not significantly different than the Filtek Z350 as confirmed by SEM. However, under all testing conditions, Filtek Flow revealed the lowest mean Ra values except for polished specimens after either hand or US scaling; there was insignificant difference between Filtek Z350 and Filtek Flow. ConclusionsScaling method tends to have material dependent effect on the Ra. All polished material's Ra exceeded the critical threshold roughness values. Clinical significanceRoutine periodontal scaling and prophylactic polishing of nano-filled resin restorations should be carried out with caution. Nano-filled flowable resin composite can be recommended in Class V restorations.