title: Therapeutic accuracy of the completely customized lingual appliance WIN : A retrospective cohort study.
abstract: OBJECTIVE
  The aim of this retrospective cohort study was to assess the accuracy of the completely customized lingual appliance WIN (DW Lingual Systems, Bad Essen, Germany) employing a three-dimensional (3D) comparison between the setup and the final result.
  
  
  METHODS
  The setup and final models of 20 consecutively debonded patients (40 jaws; 7 males, 13 females; mean age 15.76 ± 4.45 years) with various malocclusions of a private practice specialized in orthodontics were digitalized using a 3D scanner. The 3D models of the setup and the final model of each jaw were then digitally matched using the best fit algorithm and segmented into single teeth. After placing individual coordinate systems, the homologous teeth of the setup and the final model were matched to be able to calculate the exact deviations of all rotational and translational components. The t test for unpaired samples, Kruskal-Wallis tests, U tests, and ANOVA with Duncan post hoc test were applied statistically.
  
  
  RESULTS
  Regarding the incisors, the angle discrepancies between the setup and the final result appeared to be less than 3° (torque 2.96°; tip 2.04°; rotation 2.00°). The translations showed mean values less than 0.3 mm (mesiodistal 0.16 mm; buccolingual 0.15 mm; vertical 0.29 mm). Slightly higher values could be measured in the lateral segments regarding rotations (torque 5.18°; tip 3.10°; rotation 3.70°) as well as regarding translations (mesiodistal 0.26 mm; buccolingual 0.64 mm; vertical 0.36 mm).
  
  
  CONCLUSIONS
  Using the completely customized lingual appliance WIN, it is possible to achieve the final result predicted by the setup with a high accuracy.
authors.affiliation: Kieferorthopädische Fachpraxis Baden-Baden, Sophienstraße 22, Im Kaiserhof, 76530, Baden-Baden, Germany. ap@dr-pauls.de.
authors.forename: Alexander
authors.initials: A
authors.lastname: Pauls
authors.affiliation: Poliklinik für Kieferorthopädie, Universität Düsseldorf, Düsseldorf, Germany.|Kieferorthopädische Fachpraxis Düsseldorf, Düsseldorf, Germany.
authors.forename: Manuel
authors.initials: M
authors.lastname: Nienkemper
authors.affiliation: Klinik für Kieferorthopädie, Medizinische Hochschule Hannover, Hanover, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Schwestka-Polly
authors.affiliation: Klinik für Kieferorthopädie, Medizinische Hochschule Hannover, Hanover, Germany.|Kieferorthopädische Fachpraxis Bad Essen, Bad Essen, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Wiechmann
mesh_terms: D000293:Adolescent; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008310:Malocclusion / Q000473:pathology* / Q000628:therapy*; D016382:Orthodontic Appliance Design; D016910:Orthodontic Brackets; D009969:Orthodontic Wires; D017755:Prosthesis Fitting / Q000379:methods*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014087:Tooth Movement Techniques / Q000295:instrumentation*; D016896:Treatment Outcome
keywords: 3D scan; Completely customized lingual appliance; Lingual brackets; Therapeutic accuracy; Treatment planning