Comparative evaluation of surface microhardness of enamel adjacent to orthodontic brackets when treated with CPP-ACP paste and Er, Cr: YSGG laser irradiation: An in vitro study

Abstract

Fixed orthodontic treatment has a lot of benefits for the patients, but it is not without any potential risks. The most common side effect of orthodontic treatment with fixed appliances is in the form of incipient caries lesions around brackets and which is mainly due to limitation on self-cleansing mechanism. To evaluate the effect of Er, Cr: YSGG laser irradiation and CPP-ACP paste used alone or in combination on the surface microhardness of enamel adjacent to orthodontic brackets.Initially starting with bonding brackets to each tooth and making acrylic resin blocks. Then LASER irradiation with appropriate settings was performed.200 non-carious extracted human maxillary first premolars were bonded by metal brackets and were tested for microhardness on Vickers machine. They were randomly divided into 5 groups followed by treated with different caries prevention methods, then subjected to PH cycling model. All teeth were tested for surface microhardness in a 3mmx3mm area surrounding the orthodontic bracket. The mean VHN value of all the groups were found to be highly statistically significant. The highest mean VHN value was found in the group 5 followed by group 2, group 3 and group 4 and least mean VHN in group 1.Combination of ER, CR:YSGG laser irradiation and CPP-ACP paste shows a highly effective preventive measure for white spot lesion. LASER irradiation with specific guidelines as followed m in this study is a more effective preventive measure as compared to CPP-ACP Paste application followed at regular intervals.