Effect of alcoholic beverages on shear bond strength of composites to enamel

BACKGROUND: Longevity of composite restoration in the oral cavity is dependent on various factors. One such factor is exposure to various foods and beverages which could alter the properties of the material. AIM: The aim of this in vitro study was to evaluate the effect of most widely consumed alcoholic beverages on shear bond strength of composites to enamel. MATERIAL AND METHODS: A total of seventy human premolars were embedded in acrylic resin blocks. Labial enamel surfaces was flattened, etched, bonded, and restored with composite resin (Tetric N Ceram – Ivoclar Vivadent AG, Schaan, Liechtenstein). The specimens were randomly divided into four groups: Group I: beer; Group II: wine; Group III: whiskey, and Group IV: artificial saliva. Group I to Group III were again divided into moderate (Group IA, IIA, and IIIA) and heavy (Group IB, IIB, and IIIB) consumption subgroups. The specimens were soaked in their respective groups for 90 min daily in Group IA, IIA, and IIIA and for 30 min every alternate day in Group IB, IIB, and IIIB until 30 days. Universal testing machine was used to determine the shear bond strength of composite with enamel. STATISTICAL ANALYSIS USED: The values obtained were statistically analyzed using two-way analysis of variance followed by post hoc test with the significant level set at P < 0.05, using GraphPad prism software version 6.01. RESULTS: Group IIB showed the highest reduction in shear bond strength, with a mean value of 6.6 ± 1.2 Mpa in comparison to control with a mean value of 21.8 ± 1.6 Mpa. CONCLUSION: As the content of alcohol and time of exposure increased along with a decrease in the pH of alcoholic beverages, shear bond strength between composite and enamel decreased.