Purpose: To compare the effect on enamel demineralization following fluoride rinse or casein phosphopeptide calcium phosphate complex (CPP-ACP) after fixed appliance orthodontic treatment.

Methods: The study population consisted of 21 post-orthodontic patients (13 females, 8 males, 84 affected teeth) with white spot lesions (WSL). They were divided into 3 groups with 28 affected teeth in each group. Participants in the control group were brushed with fluoride toothpaste twice a day. Participants in the fluoride group were instructed to rinse the mouth with 20mL 0.01% sodium fluoride rinse in addition to brushing twice a day. Participants in CPP-ACP group were instructed to use tooth moss after brushing their teeth twice a day for 6 months. SPSS 17.0 software package was used to analyze the data.

Results: Within 6 months after orthodontic treatment, white spot lesions areas of the three groups caused by enamel demineralization were all reduced in different degrees, and the differences of success rate were significant among three groups (P<0.05). CPP-ACP group achieved the highest success rate (51%) than the other group, the fluoride group (44%) and the control group (42%).

Conclusions: Brushing teeth, fluoride rinse and CPP-ACP have certain effect on remineralization of demineralized teeth in 6 months after orthodontic treatment. Compared with brushing and fluoride rinse, CPP-ACP can reduce the area of enamel demineralization more effectively.