Effects of Alcohol and Acid-Containing Beverages on the Surface Hardness of Bulk-Fill Composites

Background: The aim of this study was to investigate the changes in the surface hardness of 3 bulk-fill composites (Filtek Bulk Fill [FBF], Tetric N Ceram Bulk-Fill [TNC], and Kerr SonicFill [SF]) after immersion in acidic and alcoholic beverages.

Methods: In a cylindrical stainless steel mold, 90 disk-shaped test specimens (8 × 2 mm) of each bulk-fill composite were created. A light-curing unit (Optilux 501, Kerr) was used to polymerize the specimens for 20 s. They were then stored in distilled water at 37°C for 24 hours to ensure complete polymerization. The initial microhardness of the top surface of each sample was measured using a Vickers microhardness tester. Ten randomly selected samples of each composite were immersed in one of 3 beverages (orange juice, red wine, or diet cola) for 6 hours each day over a period of 2 weeks. After 14 days in the beverages, the samples were removed and tested for surface microhardness. A comparative analysis was conducted to assess the percentage changes in surface hardness compared to the original measurements. A one-way ANOVA was utilized to evaluate the data, with a significance level set at P < .05.

Results: Exposure to orange juice increased the hardness of the SF specimens (P < .001), while the microhardness change of the TNC and FBF composites decreased (P < .05). There was no significant difference between the materials in terms of hardness change (%) after exposure to red wine (P > .05). The hardness change values of FBF specimens immersed in diet cola showed a significantly greater decrease than those of the SF group (P < .05).

Conclusion: Unlike acidic beverages, alcohol-containing drinks do not affect the surface hardness of bulk-fill composites.