The effect of Triclosan and Zinc Sulphate on the Growth of Streptococcus Mutans and Streptococcus Sobrinus

Objective:The aim of this study is to evaluate the effect of triclosan and zinc sulphate on the growth of streptococcus mutans and streptococcuss sobrinus so as to determine the concentration required for the two preparations to inhibit the bacteria. Methods:S.mutans Ingbritt and S.sobrinus 6715 internationally referred to were selected and respectively added to triclosan at the concentration of 0.0031, 0.0063, 0.013, 0.025, 0.05 and 0.1mg/ml and to zinc sulphate at the concentration of 0.08, 0.16, 0.31, 0.63, 1.25 and 2.5 mg/ml. Besides S.mutans Ingbritt and S.sobrinus 6715 were respectively added to the preparation of triclosan and zinc sulphate at the matching concentration of 0.0031/0.08, 0.0063/0.16, 0.013/0.31, 0.025/0.63, 0.05/1.25 and 0.1/2.5mg/ml. After the above-mentioned mixture was cultured at 90% N2, 10% CO2, 37„aC for 48 hours the growth conditions of the bacteria with the preparations at different concentrations were measured with an ultraviolet spectrophotometer. Result:When the greatest inhibition rate of triclosan on S.mutans Ingbritt appeared at the concentration of 0.025mg/ml it reached 98.84°"6.4%. When the greatest inhibition rate of triclosan on S.sobrinus 6715 appeared at the concentration of 0.05 mg/ml it reached 81.66°"9.12%. When the greatest inhibition rate of zinc sulphate on S.mutans appeared at the concentration of 2.5mg/ml it was 91.23°"4.78%. When the greatest inhibition rate of zinc sulphate on S.sobrinus 6715 appeared at the concentration 1.25mg/ml it was 89.33°"1.78%. If the two were combined for use the inhibiting effect on S.mutans Ingbritt was strengthened. When the greatest inhibition rate appeared at the concentration of 0.025/0.63mg/ml it was 92.77°"2.07% while the inhibition effect on S.sobrinus 6715 was not strengthened. Conclusion:Triclosan and zinc sulphate can inhibit the growth of both Streptococusss mutans and Streptococuss sobrinus. If triclosan and zinc sulphate are combined for use its inhibiting effect on Streptococcus mutans can be strengthened but the inhibiting effect on Streptococcus sobrinus cannot.