Effect of Bleaching Gels on Surface Roughness of Nanofilled Composite Resins

Abstract

Objectives:The aim of this study was to investigate the superficial texture of composite restorations after different bleaching protocols.Methods:Filtek Supreme (S), Filtek Z350 (F), and Grandio (G) were compared to Opallis (O) and Filtek Z250 (Z) (control microhybrid composites) and to bovine enamel using three different bleaching agents: 35% hydrogen peroxide Whiteness HP (WHP), 35% Whiteness HP MAXX (WMAXX) and 16% carbamide peroxide Whiteness Standard (WS). Six specimens from each composite were treated using each bleaching agent, according to the manufacturers’ instructions. Three random sites were measured for superficial roughness (Hommel Tester T 1000) weekly for each sample. Data were analyzed for each bleaching system using two-way ANOVA and Bonferroni tests at 5% significance level.Results:WHP treatment significantly altered the Filtek Supreme composite over time. When WMAXX was used, Grandio displayed the most significant alterations in surface roughness throughout the evaluation period, which was not observed for the other nanocomposites. Using WS, Filtek Z250 presented significant surface alterations over time, which was not seen in the nanofilled materials.Conclusions:Surface roughness alteration was material and time-dependent. The bleaching gels affected nanofilled and microhybrid composite resins. Enamel was the surface less affected by bleaching.

Effect of 10% carbamide peroxide bleaching gels on surface hardness of nano filled composite resin

“…9,10 Degradation of chemical composite resin structure not only affected the decrease of surface hardness but also cause microleakage activity, surface roughness and colour stabilisation on the composite resin. [17][18][19][20] Ellias and Sajjan 17 stated that teeth whitening materials formed microleakage between the teeth surface attachment and composite resin restoration. Microleakage is one of the causes of secondary caries through the initial procedure of the penetration of saliva liquid contained bacteria in restoration borders.…”

“…This research was found that the effect of teeth whitening materials provided more impact on the roughness surface of composite restoration compared with the tooth enamel. 20 This condition happened due to the broken chain of matrix and filler caused by free radicals of peroxide, thus leads to microscopic cracks and modification surface hardness of composite resin restoration. Li et al 19 showed the period of teeth whitening materials application to composite resin restoration impact in increasing free radical of peroxide and increased the broken chain of matrix and filler and finally altered the surface roughness of composite resin restoration.…”

Effect of Bleaching Agents on the Nanohardness of Tooth Enamel, Composite Resin, and the Tooth-Restoration Interface

“…26,38 This divergence of results can be explained by the presence of different components in both the organic and the inorganic matrix of composite resins; thus, even materials of the same classification can react differently to a bleaching agent. 39 Better mechanical properties of the adhesive interface can be related to better adhesion stability and longevity of restorations. [40][41][42] However, the adhesive interface is the most susceptible to degradation, and its exposure to bleaching agents may affect the longevity of the restoration.…”

The effect of home bleaching agents on the surface roughness of five different composite resins: A SEM evaluation

“…When composite resins are submitted to bleaching agents, this chemical reaction may alter the surface characteristics (Hafez et al ., ; Rattacaso et al ., ) by accelerating the hydrolytic degradation (Wang et al ., ) and inducing oxidative cleavage of polymer chains in resin matrix (Hannig et al ., ). The degree of alterations can vary according to the composition, exposure procedure of bleaching gel and the content of resin material.…”