Treatment of Enamel Demineralization Following Orthodontic Therapy

Abstract

The early-stage, carious, white-spot lesion is a common finding on teeth in patients who have received orthodontic treatment. Recently, a calciumphosphate (Ca-P) treatment was developed to enhance remineralization of white spot lesions. We hypothesized that a rinse containing the Ca-P would promote greater remineralization of demineralized enamel in vivo than a fluoride (F)-containing rinse or a placebo rinse. Thirty post-treatment orthodontic patients with demineralized white spot lesions on one or more of the six maxillary anterior teeth were selected and randomly assigned to three equal groups for a double-blind study. One group was given the placebo rinse. Another group was given a rinse with the same ingredients as the placebo rinse plus 0.055% F. The third group was given a rinse with the same ingredients as the F rinse plus calcium, phosphate, and magnesium salts. In addition, all subjects used a 0.011% F dentifrice before rinsing. Two different methods were used to determine the initial extent and subsequent de- or remineralization of the white spot lesions at the debonding appointment (baseline), and at one, three, and six months after the baseline reading: 1) visual inspection, in which two examiners estimated the severity and location of the lesions, and 2) quantitative laser fluorescence (QLF), in which the depth and area of the lesions were determined more objectively. Lnterexaminer agreement was almost perfect for the clinical exams. All three groups were significantly different with regards to reduction of number of white spots according to the clinical scoring. The placebo rinse group had the greatest reduction followed by the Ca-P group and the fluoride group. The QLF data showed no significant overall group differences for any of the measurements except total lesion depth. The placebo group had a significantly greater reduction of total lesion depth at the last examination than the Ca-P group (p < 0.05). The data suggested that different mechanisms may exist for remineralization of large and small lesions and that remineralization of a lesion with a lower concentration of fluoride, such as that used with the placebo rinse and the fluoride dentifrice, may result in greater remineralization of white-spot lesions.