Evaluation of antibiofilm effect of vancomycin, melatonin, and boric acid combination on caries due to microleakage under prosthetic restoration

English (OpenAlex)

Aims: Drug-resistant oral bacteria causing dental caries under prosthetic restorations have become a significant clinical challenge that needs to be addressed. This study aims to demonstrate the antibiofilm effect of vancomycin (VAN) combined with melatonin (MEL) and boric acid (BOR) against biofilm formation caused by Escherichia coli (E. coli) and Lactobacillus acidophilus (L. acidophilus) on dentin of tooth surfaces under restorations due to microleakage. Methods: Extracted human teeth, free from caries, resorption, or fractures, were collected by slicing 2 mm dentin discs. A total of 64 dentin discs were inoculated with E. coli and L. acidophilus and randomly assigned to five experimental groups: MEL, BOR, MEL+VAN, BOR+VAN, and MEL+BOR+VAN, along with a control group. Antibiofilm activity and combination indices were analyzed using the MTT viability test and the Chou-Talalay method, respectively. The biofilm structure was examined using scanning electron microscopy. Results: MEL and VAN demonstrated antimicrobial effects against E. coli and L. acidophilus bacteria in unary combinations, while BOR showed ineffectiveness. However, a notable synergistic interaction was observed in the binary combinations of VAN. Interestingly, a significant synergistic effect (CI