Oral Health Prev Dent 12 (2014), No. 2 3. June 2014
Oral Health Prev Dent 12 (2014), No. 2 (03.06.2014)
Page 157-162, doi:10.3290/j.ohpd.a31663, PubMed:24624389
Antibacterial Effect of Iranian Green Tea Containing Mouthrinse vs Chlorhexidine 0.2%: An In Vitro Study
Ardakani, Mohammad Reza Talebi / Golmohammadi, Shima / Ayremlou, Sara / Taheri, Soudabeh / Daneshvar, Sedighe / Meimandi, Mansour
Purpose: Considering the antioxidant, anti-inflammatory and antimicrobial properties of green tea, this study aimed to evaluate the antibacterial effect of mouthrinses containing green tea extract vs 0.2% chlorhexidine on selected microorganisms in vitro.
Materials and Methods: The antibacterial activity of both mouthrinses and the pure green tea extract was assessed by using disk diffusion and the minimal inhibitory concentration (MIC) methods against five microorganisms: Streptococcus mutans, Streptococcus sanguis, Enterococcus faecalis, Pseudomonas aerogenosa and Escherichia coli. Growth inhibition zones were measured in mm after 24 h of incubation at 37°C. The two mouthrinses were assessed at concentrations of 1, 2, 4, 8, 16, 32, 64, 128, 256 and 512 mg/ml to determine the MIC, which was interpreted as the lowest concentration of the agent that completely inhibited the growth of the test species.
Results: 0.2% chlorhexidine produced a larger zone of growth inhibition than did the mouthrinse made of green tea extract (P < 0.01). Paradoxically, the growth inhibition zones of the tested bacteria were significantly larger in pure extract of green tea than in 0.2% chlorhexidine (P < 0.01). The chlorhexidine mouthrinse inhibited the growth of all tested species and exhibited significantly lower MICs than did the green tea mouthrinse (P < 0.01).
Conclusions: Even though the mouthrinse made with green tea extract presented an in vitro antimicrobial activity inferior to 0.2% chlorhexidine, the pure extract had considerable bactericidal effect.
Keywords: antibacterial effect, 0.2% chlorhexidine, green tea, mouthrinse