Abstract: Objective: To explore the effects of different ligation methods on the plaque index(PLI) and sulcus bleeding index(SBI) of patients with orthodontic treatment.Methods: Ninety patients with orthodontic treatment were randomly divided into the rubber band ligation group(group Ⅰ) and ligature group(group Ⅱ) and AO self-ligating group(group Ⅲ) according to the different ligation methods.The PLI and SBI in three groups were measured at 6 months before and after treatment.Results: The differences of PLI and SBI between group Ⅰ,group Ⅱ and group Ⅲ before treatment were not statistically significant(P>0.05).Compared with these before treatment,the PLI and SBI in 3 groups after 3 months of treatment significantly increased(P<0.01).The PLI and SBI in group Ⅰ after 6 months of treatment were significantly higher than these in group Ⅱ and group Ⅲ(P<0.01).After 6 months of treatment,the PLI in group Ⅱ was significantly higher than that in group Ⅲ(P<0.01),and the difference of SBI between group Ⅱ and group Ⅲ was not statistically significant(P>0.05).Conclusions: The effects of the self-ligating and ligature on preventing dental plaque and gingivitis are better than these of rubber band ligation,and which can be applied in orthodontic treatment.