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

Abstract

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.