Effect of Garlic Extracts on Streptococci and Mutans Streptococci, in Comparison to Chlorhexidine Gluconate (A comparative in vitro and in vivo study)

Jinan M. Rashad, Sulafa K. El-Samarrai


Background: Garlic is a medicinal plant with anti-inflammatory, antimicrobial and immune-boosting properties. The aim of the present study was to assess and compare the effect of garlic extracts with those of chlorhexidine gluconate and de-ionized water against viability counts of Streptococci and Mutans Streptococci.
Materials and Methods: The effect of different concentrations of garlic extracts (water and ethanol) on growth and viability counts of Mutans Streptococci in comparison to 0.2% chlorhexidine gluconate and de-ionized water were evaluated through a series of in vitro experiments. Water garlic extract (10%), were tested in comparison to chlorhexidine (0.2 %) and de-ionized water, regarding the effect on viability counts of salivary Mutans Streptococci and Streptococci, among a group of volunteers.

Results In vitro experiments; Statistically non significant reduction in the viable counts was recorded when garlic extracts (water and ethanol) were used at concentration 5%, while at higher concentrations both types of garlic extracts showed statistically signif- icant reduction in the counts of Mutans Streptococci (P<0.05).

Rinsing with any one of these agents resulted in a slight decrease in the salivary counts of bacteria, while chlorhexidine showed a sharp reduction in the counts of bacteria which was highly significant (P<0.001). For Mutans Streptococci, a highly significant differences were found between the three mouth rinses (P<0.001) in the counts of bacteria in the following time points (after 30 minute, after one hour and after two hours of rinsing). Within these times chlorhexidine was shown to be the most effective in reducing the counts of these bacteria followed by water garlic extract.
Conclusion: Garlic extract was effective against Mutans Streptococci when tested both in vitro and in vivo.


Garlic extracts, chlorhexidine, Streptococci, Mutans Streptococci.

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DOI: http://dx.doi.org/10.26477/idj.v35i2.147


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