The Effect of Chemical Degradation and Polishing on the Gloss of Composite Dental Materials

Abstract

This aim of this study was to investigate surface gloss changes of different composite dental materials after chemical degradation or polishing. Five different composites were used (Evetric, GrandioSO, Admira Fusion, Filtek Z550, Dynamic Plus). The gloss of the tested material was measured with a glossmeter before and after chemical degradation in different acidic beverages. Statistical analysis was performed using a t-test for dependent samples, ANOVA, and a post hoc test. For comparison between groups, a level of significance was set at 0.05. Initial gloss values ranged from 51 to 93 at baseline to 32 to 81 after chemical degradation. The highest values were obtained for Dynamic Plus (93.5 GU) and GrandioSO (77.8 GU), followed by Admira Fusion (82 GU) and Filtek Z550 (70.5 GU). Evetric showed the lowest initial gloss values. After acidic exposures, the gloss measurements revealed different patterns of surface degradation. The results showed that the gloss of the samples decreased with time regardless of the treatment. The interaction between chemical-erosive beverages and the composite could lead to a decrease in the surface gloss of the composite restoration. The nanohybrid composite showed less gloss changes under acidic conditions, suggesting that it is more suitable for anterior restorations.

Surface roughness and gloss retention of bioactive resin composite after simulated toothbrush abrasion

“…At each measurement, the sample was positioned on a black cover to eliminate the effect of external light. For each sample, six GU values were obtained by rotating the sample at 90°and averaged to obtain a single value [6,7].…”

“…In addition to the prevention of secondary caries, the long-term success of a restoration relies on several other factors such as mechanical properties, diminished wear, and esthetic properties such as color stability and gloss retention [5]. However, oral environmental factors are known to affect the integrity and longevity of restorative materials [5][6][7]. For instance, mechanical abrasion caused by toothbrushing is considered a critical factor affecting the restoration's surface roughness and gloss, which compromises the clinical performance of the restorations [7].…”

“…Composite restorations with high gloss tend to have a more natural appearance and are indistinguishable from adjacent teeth structure. Gloss of the resin composite materials is directly related to a smooth surface texture of the restoration [6]. In addition to its influence on the gloss, a smooth surface enhances the color stability and reduces the formation and accumulation of plaque, and therefore gingivitis and caries, as surface roughness (Ra) value of 0.2 μm is considered a threshold for bacterial retention [8].…”

Alterations in Surface Gloss and Hardness of Direct Dental Resin Composites and Indirect CAD/CAM Composite Block after Single Application of Bifluorid 10 Varnish: An In Vitro Study

“…The durability of the resin composites is significantly influenced by the properties of the surface. Chemical treatments or even preventive measures like fluoride varnish and other dental hygiene products can harm the surface of restorative materials [9,10]. They may have adverse effects on resin composites, like discoloration, surface erosion, reduced surface hardness, and the dissolving of inorganic fillers [11].…”

“…The surface quality of the material directly affects its ability to reflect direct light. Surface gloss is frequently used to determine dental materials' surface characteristics [9]. The gloss is a result of the arrangement of light reflected on the surface and is closely correlated with surface roughness [9].…”