Effect of different beverages on surface properties and cariogenic biofilm formation of composite resin materials

The consumption of certain beverages may affect the physical and biological properties of resin composites (RCs) according to type. This in vitro study aimed to evaluate the surface properties and cariogenic biofilm formation in microhybrid and nanohybrid RCs after immersion in different beverages. The effects of four beverages (distilled water-control, tea, coffee, and cola) on two RCs (microhybrid and nanohybrid) were evaluated. Changes in the surface properties were evaluated for each group using surface roughness measurement (n = 10), scanning electron microscopy (SEM) (n = 4) observation, and energy-dispersive X-ray spectroscopy (EDX) (n = 5) analysis. In vitro Streptococcus mutans biofilm formation on the specimens of each group was determined using confocal laser scanning microscopy and SEM analysis (n = 14). The data were analyzed using two-way analysis of variance, with Bonferroni as a post-hoc test and Pearson's correlation (p < .05). Microhybrid RC presented more surface roughness (p = .014) and cariogenic biofilm formation (p = .040). The surface roughness (F = 0.733, p = .536) and cariogenic biofilm formation (F = 1.685, p = .181) values were not affected by the beverages. However, according to qualitative SEM and EDX measurements, these parameters varied depending on the beverage groups. No correlation was found between surface roughness and cariogenic biofilm formation (r = 0.135, p = .287). Microhybrid RCs had a rougher surface and a higher amount of cariogenic biofilm formation than nanohybrid RCs after being subjected to different beverages.