Longitudinal development of caries lesions after orthodontic treatment evaluated by quantitative light-induced fluorescence.

ABSTRACT

INTRODUCTION: The aim of this investigation was to use quantitative light-induced fluorescence to study the natural behavior of white-spot lesions that developed in orthodontic patients during treatment with fixed orthodontic appliances, after the removal of those appliances. METHODS: The sample comprised 58 consecutively recruited patients who were at least 12 years old and who had been treated with a fixed appliance for at least 1 year in the department of orthodontics at the Academic Center for Dentistry Amsterdam, The Netherlands. They were examined with quantitative light-induced fluorescence for the presence and the extent of caries on the buccal surfaces of their teeth directly after debonding and 6 weeks and 6 months later. The fluorescence loss (DeltaF [%]) and area of lesions (mm2) were determined for all lesions found. RESULTS: A total of 421 carious lesions were recorded at debracketing with an average fluorescence loss (DeltaF(0)) of 10.3% (SD, 5.4%). During the study, 15 lesions were lost from quantitative light-induced fluorescence analysis: 11 lesions (DeltaF(MAX,0) >25%) in 2 subjects were restored, and 4 were not analyzed because they were not imaged properly. Lesions varied from incipient, ie, white spot (DeltaF(0) <10%, n = 257), to advanced, ie, dentinal (DeltaF(0) >25%, n = 12). A small lesion improvement was seen 6 weeks after debracketing (P <.01), and a further lesion improvement was seen after 6 months (P <.01). Incipient lesions on average showed a smaller improvement (relative decrease, 2%; SD, 20%) than lesions with DeltaF(0) >10% (relative decrease, 12%; SD, 20%; P <.01). CONCLUSIONS: The lesions that developed during orthodontic treatment improved once the fixed appliances were removed even when they were advanced, but the overall regression was small.