To evaluate the short period clinical responses after sealed garlicin and formocresol small cotton ball in the root canal entrance to treat chronic periapical periodontitis.Treatment records of 185 teeth with chronic periapical periodontitis were compared. Of them, 94 teeth were treated by sealed small garlicin cotton ball in the root canal entrance, 78 were treated by sealed small formocresol cotton ball in the root canal entrance, and the other 13 were treated by sealed small normal saline cotton ball. The curative effects were evaluated through clinical observation.The ratios of acute reaction in 3 days following sealed garlicin, formocresol and normal saline small cotton ball were 5.1%, 10.7%, and 50% in the anterior teeth, and 5.5%, 8.0%, and 60%, in the posterior teeth, respectively.The clinical curative effects were similar between garlicin and formocresol in the short period. Formocresol can be substituted by garlicin.