METHODS : Decoction infusion of Chinese nutgall and standard sample of tannin were confected into 5 different concentrations to observe Chinese nutgall 's effect on streptococcus mutans and streptococcus sobrinus by Barer-Kirby ( B-K ) drug susceptibility test method .

方法：本实验采用 纸片扩散法研究五种浓度五倍子煎剂、五倍子浸剂、 鞣酸标准品抑制变链菌及远缘链球菌生长的作用。