Occurrence and severity of enamel decalcification adjacent to bracket bases and sub-bracket lesions during orthodontic treatment with two different lingual appliances

Abstract

SummaryBackground:Using lingual enamel surfaces for bracket placement not only has esthetic advantages, but may also be suitable in terms of reducing frequencies of enamel decalcifications.Objective:To test the null-hypothesis that there is no significant difference in enamel decalcification or cavitation incidence adjacent to and beneath bracket bases between two lingual multi-bracket (MB) appliances that are different in terms of design, material composition, and manufacturing technology (group A: WIN, DW-LingualSystems; group B: Incognito, 3M-Unitek), taking into account patient- and treatment-related variables on white spot lesion (WSL) formation.Methods:Standardized, digital, top-view photographs of 630 consecutive subjects (16214 teeth; n Incognito = 237/6076 teeth; n WIN = 393/10138 teeth; mean age: 17.47±7.8; m/f 43.2/56.8%) with completed lingual MB treatment of the upper and lower permanent teeth 1–7 were screened for decalcification or cavitation adjacent to and beneath the bracket bases before and after treatment, scored from 0 to 7. Non-parametric ANOVA was used for main effects ‘appliance type’, ‘gender’, ‘treatment complexity’, ‘grouped age’ (≤16/>16 years), and ‘treatment duration’ as covariable, at an α-level of 5%.Results:About 2.57% [5.94%] of all teeth in group A [B] developed decalcifications. Subject-related incidence was 9.59% [16.17%] for upper incisors in group A [B], and 12.98% [25.74%] for all teeth 16–46. There were significant effects by gender, age, and treatment duration.Conclusion:The null-hypothesis was rejected: sub-bracket lesions were significantly less frequent in group A, while frequencies of WSL adjacent to brackets were not significantly affected by appliance type. In view of the overall low incidences of lingual post-orthodontic white-spot lesions, the use of lingual appliances is advocated as a valid strategy for a reduction of enamel decalcifications during orthodontic treatment.

Therapeutic accuracy of the completely customized lingual appliance WIN

“…In addition to advantages shown for patients, the risk of developing white spot lesions appears to be drastically reduced when using lingual compared to labial appliances [7, 8, 15, 17]. …”

Comparison of potential long-term costs for preventive dentistry treatment of post-orthodontic labial versus lingual enamel cavitations and esthetically relevant white-spot lesions: a simulation study with different scenarios

“…An increased susceptibility for caries formation in has been reported by a majority of studies on post-orthodontic enamel damages [1, 13]. Our model is comparable in terms of age-related caries activity given that both studies used as basis for our simulation have excluded patients of an age > 18 years at the time point of the start of treatment.…”

“…It was the aim of our study to provide a more refined and more detailed follow-up cost calculation for labial WSLs, and also to calculate whether the use of lingual appliances may be suitable for reducing the extent of those follow-up costs, by choosing enamel areas for bracket placement that are known to be less susceptible to caries formation [10–13].…”

“…The present model simulates a very high sample size of 1,000,000 orthodontic treatments in order to achieve robust cost calculations, but it also necessarily simplifies some potential factors that may have an influence on WSL or cavitation treatment costs: Labial or lingual enamel decalcification or cavitation incidence rates per month were based on two of the largest reports on the subject, with adequate sample sizes of least of 350 patients [2, 12]. Previous reports on lingual post-orthodontic lesions yielded slightly decreased numbers of WSL compared to the report used here but were also smaller in sample size [10, 11, 13]. Many of the reports on labial post-orthodontic lesions also did not assess decalcifications in complete dental arches, but in specific tooth groups, such as upper incisors only [4].…”

“…Three-dimensionally controlled fixed orthodontic treatment may be performed using conventional labial attached MB appliances, or lingual MB appliances [2, 8, 9]. Whilst lingual MB treatment may be initially more laborious and costly due to external fabrication costs, the incidence of lingual post-orthodontic WSL and cavitation has been reported to be distinctively lower in terms of frequencies and in extent, in comparison to labial MB treatment [10–13]: Choosing lingual enamel areas for bracket placement that are known to be less susceptible to caries formation, the incidence of lingual post-orthodontic enamel decalcifications has been reported to be reduced up to the factor of ten for distinctive groups of teeth [12]. In a consecutively recruited sample of 385 subjects with a total of 10,162 trial teeth, 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%] was reported.…”