Surface quality evaluation through 3D profilometry of dental restoration performed in a clinical simulated environment

Abstract

This study evaluated the surface quality of Class V composite resin restorations, comparing the surface roughness resulting from applying three techniques for finishing and polishing in a condition of clinical simulated environment by using artificial dental arcade. Beyond the aesthetic aspect, the importance of the surface quality of the restoration is associated with biofilm accumulation that occur on the teeth restored surface depending on the roughness level, leading to carious lesions and gingivitis. The minimum roughness considered ideal to avoid the accumulation of bacterial biofilm, is 0.2 m, and 0.5 m for tactile perception. Most of the evaluations of the surface quality of restorative materials are performed in flat specimens, and the results can significantly differ from the clinical scenario. The present work discloses how heterogeneous the surface quality may result when dealing with natural teeth. The finishing and polishing techniques selected in this work comprised diamond burs and rubber points, diamond burs and surface sealant, and abrasive discs, for restoring premolar natural teeth using a commercial composite resin. The surface quality of the restoration resulting from the three techniques was investigated through Ra, Rt, Rp, R, Rk, Rpk, Rvk and RSm roughness parameters, extracted from 3D topography maps. It was found that the use of abrasive discs (G3) promoted better surface quality, with mean Ra roughness near 0.4 m, against 0.6 m for the surface sealant group (G2) and 1.0 m for the rubber points group (G1). It was evidenced that, together with Ra, analyses of roughness parameters regarding the proportion of peaks and valleys, in this case, Rp and Rpk, and roughness spacing, RSm, were significant to gain confidence and reveal reliable screening of the performance between the three techniques, with the best surface condition of the restored area resulting from the use of abrasive discs.