Time- and concentration-dependent cytotoxicity of antibiotics used in endodontic therapy

Abstract

ObjectiveNew drugs have to be assessed in endodontic therapy due to the presence of microorganisms resistant to therapeutic procedures. Thus, this study evaluated the time- and concentration-dependent cytotoxicity of different antibiotics used in endodontic therapy.Material and MethodsHuman gingival fibroblasts were treated and divided into the following experimental groups: Group I - control; Group II - ciprofloxacin hydrochloride; Group III - clyndamicin hydrochloride; and Group IV - metronidazole. Each drug was used at concentrations of 5, 50, 150, and 300 mg/L for 24, 48, 72, and 96 h. Cytotoxicity was evaluated by the MTT assay [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] and spectrophotometric reading of ELISA plates. The results were analyzed by BioEstat 4.0 software using Kruskal-Wallis and Dunn’s tests at a significance level of 5%. Cell viability was assessed for the different concentrations and times.RESULTSAll drugs presented dose-dependent cytotoxicity. Concentrations of 5 and 50 mg/L produced viable fibroblasts at all experimental times in all groups.ConclusionsCell viability at 24 h was greater than in the other experimental times. Comparison between the same concentrations of antibiotics at different times showed that metronidazole presented the highest cell viability at 72 and 96 h compared to the other antibiotics, whereas clyndamicin hydrochloride showed higher cell viability at 72 h than ciprofloxacin hydrochloride.

Metronidazole Decreases Viability of DLD-1 Colorectal Cancer Cell Line

“…Moreover, it seems that the longer the exposition to the drug occurs, the better anticancer effect it can cause. Similar results were obtained by Ferreira et al 22 Authors presented time-and concentration-dependent cytotoxicity of antibiotics used in endodonic therapy. All drugs (ciprofloxacin, clyndamicin, and MTZ) tested on human gingival fibroblasts showed dose-dependent cytotoxicity.…”

Influence of fluoroquinolones on viability of Balb/c 3T3 and HepG2 cells

“…In the study performed using fibroblasts Balb/c 3T3, no decrease in cell viability after 24 h exposure to ciprofloxacin at concentrations 12.5, 25, 50 µM (4.14, 8.28, 16.57 µg/mL) was observed (23). Cytotoxic effects of ciprofloxacin against human fibroblasts were reported at concentration >50 µg/mL following longer (>48 h) exposure (6,11).…”

Indications of antibiotic prophylaxis in dental practice–Review

“…Ciprofloxacin is one of the common drugs used for endodontic infections. The effective action against oral anaerobes, gram positive aerobic organisms (Staphylococcus aureus, Enterobacter species and Pseudomonas) demands the need of ciprofloxacin for endodontic infections [15] . Metronidazole is a synthetic antimicrobial agent, which is bactericidal and most effective against anaerobes.…”