Effects of monomer compositions on physicochemical properties of composite resins

The aim of this study was to evaluate the cohesive strength (CS), surface roughness (Ra), and weight loss (WL) of different composite resins. Three composite resins (Filtek Z100; Filtek Z350; Filtek P90, 3M ESPE) were tested. To evaluate CS, an hourglass silicone mold (11 x 2 x 1 mm) was used (n = 10). The Ra and WL tests were performed using a circular mold (5 x 2 mm, n = 10). The composite resins were light-cured with an LED light curing device (FreeLight 2, 3M ESPE) for 40 s and 1000 mW/cm(2). The CS test was performed using a universal testing machine (Instron 4411, Instron) at a crosshead speed of 0.5 mm/ min and cell load of 500 N. The initial mass weight was registered (analytical digital balance) and the initial Ra reading evaluated using a profilometer (Surftest 211, Mitutoyo). The specimens were submitted to 30,000 brushing cycles. The WL and the final Ra were evaluated. All data were subjected to one-way ANOVA, followed by Tukey's test (p < 0.05). Filtek Z100 showed the highest values of Ra and Filtek Z350 the lowest values of Ra. When considering CS, Filtek Z350 and Z100 had the highest mean values. Filtek P90 had the highest mean value of WL. The organic matrix and the type, shape, and size of fillers may influence the physicochemical properties of composite resins311112031208sem informaçã