Prevention of enamel demineralization during orthodontic treatment: an in vitro study using pit and fissure sealants.

Enamel demineralization during active orthodontic treatment remains a significant problem. The purpose of this in vitro study was to evaluate the efficacy of applying a light-cured unfilled resin, a conventional pit and fissure sealant, to the labial surface of teeth with previously placed orthodontic appliances to prevent demineralization. Orthodontic brackets were bonded to 40 extracted human teeth with a commercially available orthodontic adhesive. The exposed labial surfaces of 30 teeth (experimental group) were sealed with a clear, light-cured, unfilled resin. The remaining 10 teeth (control group) were left unsealed. Both groups were placed in a demineralization environment, and then all teeth were sectioned and examined under polarized light microscopy for the presence or absence of enamel demineralization. Every member of the control group exhibited demineralization of the entire exposed labial surface, whereas 80% of the sealed teeth exhibited no demineralization. Small, isolated areas of enamel loss were seen in six of the sealed teeth representing "breaks" in the sealant layer. The results of this study indicate that light-cured sealant treatment after orthodontic appliance placement significantly reduces enamel demineralization.