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Updated: Aug 19, 2025
Author Spotlight: 3D Movement Assessment of Maxillary Posterior Teeth in Clear Aligner Treatment
Published on: February 23, 2024
The effects of lingual buttons, precision cuts, and patient-specific attachments during maxillary molar distalization
Lurong Jia1, Chunjuan Wang1, Lingjie Li1
1Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China; Stomatological Hospital of Chongqing Medical University, Chongqing, China; Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China.
Introduction:
This study aimed to analyze the biomechanical effects of the combined use of clear aligners (CA) and auxiliaries (precision cuts, lingual buttons, and patient-specific attachments) on mesial tipping and extrusion of the premolars during maxillary molars distalization.
Methods:
Three-dimensional finite element method was employed to simulate clinical scenarios of CA with different auxiliaries for molar distalization. As such, 200 g of distal force was applied to the microimplants from the notches, lingual buttons, and hooks. Orthodontic tooth movement and the hydrostatic pressure in the periodontal ligament were compared.
Results:
Adding auxiliaries can provide the maxillary arch anchorage and promote the distal tipping of premolars and retroclination of maxillary incisors. In contrast, this effect was more pronounced in patient-specific attachment applications than in other types of auxiliaries. The independent application of the CA caused mesial tipping and extrusion of the premolar and also caused the incisor proclination.
Conclusions:
The anchorage loss caused by the CA alone could be alleviated with the assistance of auxiliaries. Notably, patient-specific attachments further reinforce the anchorage of the anterior arch by incorporating anchor teeth as 1 anchorage unit.
