An in vitro comparison of four antibacterial agents with and without nicotine and their effects on human gingival fibroblasts

Background The purpose of the study was to compare anti‐bacterial activity of 0.12% chlorhexidine (CHX), 10% povidone iodine (PVD), Vega oral care gel (VEGA), and antioxidant gel (AO) on Streptococcus mutans, Streptococcus sanguis, Fusobacterium nucleatum, and Porphyromonas gingivalis with and without nicotine and to evaluate their effects on human gingival fibroblasts (HGFs). Methods S. mutans, S. sanguis, P. gingivalis, and F. nucleatum were incubated with serial dilutions (1/4, 1/8, 1/16, 1/32, and 1/64) of anti‐bacterial agents in media (with and without nicotine). Minimum inhibitory and minimum bactericidal concentrations (MIC/MBC) were measured, and confocal microscopy was performed. HGFs were exposed to serial dilutions (1/10, 1/100, 1/1000, and 1/10,000) of antibacterial agents with media. Water‐soluble tetrazolium‐1 (WST‐1) assay and lactate dehydrogenase (LDH) assay were used to assess proliferation and cytotoxicity towards HGFs. Results CHX and PVD significantly inhibited growth of all bacterial species (P