Completely Customized Lingual Appliances Reduce the Risk of Enamel Decalcification many Times over

Background and Aim: The formation of enamel decalcifications or white-spot lesions (WSLs) is a frequent and undesired side-effect of conventional fixed orthodontic treatment. The use of lingual appliances may be suitable for reducing the extent of those side-effects, by choosing enamel areas for bracket placement that are known to be less susceptible to caries formation: It was the aim of the study to assess the incidence of lingual WSLs and cavitations resulting from fixed lingual orthodontic treatment, taking into account different separate tooth groups (12-22; 13-23;16-46; 17-47) as well as the impact of potential treatment-related co -factors such as treatment duration, sex, and grouped age. Subjects and Method: In this retrospective study, we assessed the incidence of both WSLs and cavitations in 385 consecutive subjects with a total of 10162 valid teeth treated with the fully customized lingual appliance WIN (DW Lingual Systems, Bad Essen, Germany), using high resolution top-view photographs taken before, during, and following completion of active treatment. The exclusion criterion was a subject's age: > 18 years at the start of treatment. Statistical analysis was descriptively, and by non -parametric ANOVA, adopting a significance level of 5%. Results: The mean lingual WIN appliance treatment duration was 22.3 +/- 7.18 months. There was a tooth-related WSL [cavitation] incidence of 5.8% [0.2%] in upper incisors, and a subject related (i.e., subjects with at least one new WSL) incidence of 13.8% [0.8%]. Considering complete upper and lower dental arches including second molars (teeth 17-47), there was a tooth -related WSL [cavitation] incidence of 3.2% [0.1 %]. Occurrence of cavitations in tooth group 13-23 was significantly increased in male patients (0.4% of all teeth 13-23). Long treatment durations had a significantly deteriorating impact on WSL formation in tooth groups 13-23, and 16-46. Conclusion: In comparison to WSL incidences resulting from vestibular fixed orthodontic treatment as reported in the literature, and depending on the tooth group, the incidence of lingual post -orthodontic enamel decalcifications is reduced up to the factor of 10. Inactive, remineralized lingual lesions do not require treatment, and do not impair smile esthetics.