Three-dimensional assessment of virtual clear aligner attachment removal: A prospective clinical study

Jeremy Dock; Flavio Copello; Iman Shirmohammadi; Jose A Bosio

doi:10.1016/j.ajodo.2024.02.006

Three-dimensional assessment of virtual clear aligner attachment removal: A prospective clinical study

Am J Orthod Dentofacial Orthop. 2024 Apr 10:S0889-5406(24)00064-7. doi: 10.1016/j.ajodo.2024.02.006. Online ahead of print.

Authors

Jeremy Dock¹, Flavio Copello², Iman Shirmohammadi², Jose A Bosio²

Affiliations

¹ Formerly, Division of Orthodontics, Department of Orthodontics and Pediatric Dentistry, University of Maryland School of Dentistry, Baltimore, Md; Currently, Private practice, Cincinnati, Ohio. Electronic address: jeremydock@gmail.com.
² Division of Orthodontics, Department of Orthodontics and Pediatric Dentistry, University of Maryland School of Dentistry, Baltimore, Md.

PMID: 38597867
DOI: 10.1016/j.ajodo.2024.02.006

Abstract

Introduction: In digital dentistry, virtual attachment removal (VAR) optimizes clear aligner therapy by enhancing efficiency for refinements and enabling prefabricated retainer production through the removal of attachments from a digital scan before the clinical removal of clear aligner attachments. This prospective clinical study aimed to evaluate the accuracy of VAR in the maxillary arch.

Methods: A total of 110 teeth were analyzed from a sample of 54 maxillary scans from 25 subjects. Models with attachments were virtually debonded using Meshmixer (Autodesk, San Rafael, Calif) and superimposed over the control group in MeshLab. Vector Analysis Module (Canfield Scientific, Fairfield, NJ) was used to calculate and analyze 3-dimensional Euclidean distances on the buccal surfaces between the superimposed models. Statistical analysis was performed using SPSS (version 23.0, IBM, Armonk, NY). The Shapiro-Wilkes (α = 0.05) test determined a nonnormal distribution of results. The Kruskal-Wallis (α = 0.05) was used to determine differences between different tooth types and the number of attachments.

Results: The VAR protocol showed no statistical differences in the root mean square between different tooth segments with an overall tendency for inadequate attachment removal. No difference between the groups was found regarding the number of attachments when used as a main factor.

Conclusions: The VAR technique is precise enough for the fabrication of retainers from printed dental models in a clinical setting and is not affected by the number of attachments on the tooth.