A LONGITUDINAL LASER FLUORESCENCE STUDY OF WHITE SPOT LESIONS IN ORTHODONTIC PATIENTS

Orthodontic treatment with fixed appliances increases the caries risk in young persons. The aim of this study was to apply a new caries diag nostic method, quantitative laser fluorescence, for longitudinal in vi vo quantification of changes in incipient enamel lesions related to fi xed orthodontic appliances. Seven young patients with active caries le sions disclosed at removal of the orthodontic brackets and bands were enrolled in the study. Caries preventive measures were intensified, in cluding dietary advice, oral hygiene instructions, and the regular use of a fluoride dentifrice. The caries lesions were monitored with the quantitative laser fluorescence method after removal of the brackets a nd once a month thereafter. For each lesion, three quantities were mea sured: lesion area (mm(2)), mean fluorescence loss (%) over the lesion , and maximum loss of fluorescence (%) in the lesion. During a 1-year follow-up period, the areas of the lesions decreased and the enamel fl uorescence lost was partly regained indicating that a remineralization process had occurred. It was concluded that,quantitative laser fluore scence seems suitable for in vivo monitoring of mineral changes in inc ipient enamel lesions, and useful for the evaluation of preventive mea sures in caries prone persons, such as orthodontic patients.