The effect of toothbrush abrasion on wear and surface roughness of direct and indirect composite laminate veneer restorations

Abstract

Direct and indirect composite laminate veneers have been frequently used, however the wear of composite restorative materials is still a major problem. Objective: This study aimed to investigate the surface roughness and wear of composite laminate veneers made by two different methods after toothbrushing simulation. Material and Methods: Ninety-six upper incisors and canines were divided into two groups: 1-Componeer prefabricated composite veneer (CPV), 2- Uveneer direct composite veneer (UDV). At the UDV group, restorations were made by using Uveneer template system with the same nanofilled composite material (Synergy D6, Coltène, Altstatten, Switzerland) of the prefabricated Componeers’. The initial surface roughness was measured with a profilometer, then the weight was measured. Before the simulation, samples were screened with a 3D extra-oral scanner. Toothbrush simulation was performed at 10,000 rotational strokes with 2.5 N. The measurements were repeated after toothbrushing simulation. Data were analyzed using variance analyses and t-tests (p < 0.05). Results: Before and after polishing, a significant difference was found between two groups’ surface roughness in both lateral incisors (p = 0.000, p = 0.000) and canines (p = 0.048, p = 0.001), respectively. After toothbrushing simulation, significant increases were observed in central and lateral incisors’ surface roughness with two methods. There was no significant difference between weight loss (p > 0.05). In 3D scans, wear rate was quite similar except UDV group central incisors. Conclusions: Surface roughness of the CPV restorations were less affected after toothbrushing simulation. However, the Uveneer template system, a facilitated treatment procedure compared to the manual buildup of direct restoration, has shown comparable results with CPV’s.