Evaluation of the Antibacterial Efficacy of Daptomycin, Gentamicin, and Calcium Hydroxide-Antibiotic Combinations on Enterococcus faecalis Dentinal Biofilm: An In Vitro Study.

AIM To evaluate the antibacterial efficacy of calcium hydroxide (CH) with antibiotic combinations: daptomycin and gentamicin against Enterococcus faecalis (E. faecalis) dentinal biofilm. MATERIALS AND METHODS Sixty freshly extracted single-rooted mandibular premolars were inoculated with E. faecalis(ATCC 29212) (n = 30) (group A) and clinical isolates (n = 30) (group B) for 3 weeks to form a biofilm. The tooth samples of groups A and B were randomly divided into three subgroups of 10 each, groups 1A and 1B (CH), groups 2A and 2B (CH+G), groups 3A and 3B (CH+D), depending on the medicaments to be placed for one week. The difference between initial and final CFU was calculated and statistically analyzed. RESULTS Among the clinical isolates, CH-antibiotic combinations were more effective than CH alone, which was statistically significant (p = 0.006). CONCLUSION The dentinal biofilm of clinical isolates of E. faecalis strains exhibited more reduction in bacterial colonies with CH in combination with antibiotics (D and G). CLINICAL SIGNIFICANCE Daptomycin and gentamicin when used as an intra-canal medicament in combination with CH are effective in eliminating E. faecalis. Keywords: Calcium hydroxide, Daptomycin, Dentinal biofilm, E. faecalis, Gentamicin.