Effectiveness of magnesium hydroxide as mouthwash for caries prevention around brackets: An OCT evaluation

BackgroundThe aim of this study was to evaluate the potential of magnesium hydroxide in the maintenance of tooth enamel integrity around orthodontic brackets under pH-cycling conditions in vitro.MethodsOrthodontic brackets were fixed to the vestibular surfaces of bovine incisors, with six groups of 15, according to exposure to test substances: group 1, brushing only; group 2, brushing plus rinsing with fluoride-containing mouthwash; group 3, immersion only, in original milk of magnesia; group 4, immersion only, in mint-flavored milk of magnesia; group 5, brushing plus immersion in original milk of magnesia; and group 6, brushing plus immersion in mint-flavored milk of magnesia. Experimental groups alternated between pH cycling and procedures described. Both brushing and immersion in solutions were performed for 1 minute, followed by washing in de-ionized water, 3 times per day for 28 days. After this, evaluation was performed using optical coherence tomography. In each group, a scanning examination for white spot lesions (around the brackets) and depth measurement of caries lesions were performed.ResultsGroup 1, in which only brushing was performed, demonstrated greater depth of caries lesions with statistical differences compared with those in groups 2 (P = 0.008), 4 (P = 0.044), 5 (P < 0.001), and 6 (P < 0.001).ConclusionThe findings from the present study suggest that the use of brushing plus rinsing with milk of magnesia is effective in reducing the depth of caries lesions compared with brushing alone in patients using orthodontic brackets.