Antimicrobial Properties and Substantivity of Gentamicin, Amoxicillin and Metronidazole (GAM) Antibiotic Solution with Chitosan as a Root Canal Irrigant – A Preliminary Study

Irrigation is one of the steps that is very crucial in a high-quality endodontic treatment. Hence, irrigant with good substantivity is essential which must not only be effective for the dissolution of the organic tissues but also effectively eliminate bacterial contamination. The aim of the study was to investigate and compare the antimicrobial efficacy of gentamicin, amoxicillin, and metronidazole (GAM) antibiotic solution, chitosan and their combination (GAMC), and analyze their sustained release property. Mueller–Hinton agar medium was inoculated with E. faecalis. The medicaments were then poured at the center of the plate in the prepared wells and incubated at 37°C. Antibacterial property of each medicament was evaluated by measuring the diameter of the zone of inhibition at the end of 48 hours. The substantivity of GAM antibiotic solution and the GAMC was checked using an ultraviolet spectrophotometer. The GAMC demonstrated the strongest antimicrobial activity and good sustained-release properties. Distilled water showed no activity, and chlorhexidine acted as the positive control. CONCLUSION: The combination of gentamicin, amoxicillin, and metronidazole (GAM) solution with chitosan (GAMC) can be used as an alternative intracanal irrigant as it was found to be a potent antibacterial agent.