Evidence map›Paper›PMID 41729442›Full record

ArticleProgress in orthodontics2026

Biomechanical effects of attachment position and pressure ridge design on maxillary arch expansion with clear aligners: a finite element analysis.

Yuanyuan Zheng, Runzhi Guo, Qingyi Dai, Weiran Li, Ping Wen, Min Wu, Yifan Lin

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Article in Progress in orthodontics, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

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2citing papers in PubMed
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1 · What the graph read from it

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3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

7 authors.

Yuanyuan Zheng *Shenzhen Maternity and Child Healthcare Hospital, Women and Children's Medical Center, Southern Medical University, Shenzhen, China.
Runzhi Guo *Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing, China.ORCID http://orcid.org/0000-0002-2232-1396
Qingyi DaiDivision of Paediatric Dentistry & Orthodontics, Faculty of Dentistry, the University of Hong Kong, Hong Kong S.A.R., China.
Weiran LiDepartment of Orthodontics, Peking University School and Hospital of Stomatology, Beijing, China.
Ping WenShenzhen Maternity and Child Healthcare Hospital, Women and Children's Medical Center, Southern Medical University, Shenzhen, China.
Min WuShenzhen Maternity and Child Healthcare Hospital, Women and Children's Medical Center, Southern Medical University, Shenzhen, China.
Yifan LinDivision of Paediatric Dentistry & Orthodontics, Faculty of Dentistry, the University of Hong Kong, Hong Kong S.A.R., China. yflin@hku.hk.ORCID http://orcid.org/0000-0002-2614-9159

Funding

Beijing Natural Science Foundation L242129Seed Fund for Collaborative Research of the University of Hong Kong 2307102537
6 · The paper itself

Abstract

objectivesTo investigate the biomechanical effects of attachment position (buccal vs. palatal) and the integration of pressure ridges on maxillary arch expansion with clear aligners using finite element analysis.

methodsFive 3D finite element models were constructed to simulate 0.2 mm of buccal expansion with different auxiliary configurations: (A) no attachment; (B) buccal attachments; (C) palatal attachments; (D) buccal attachments combined with palatal pressure ridges; and (E) palatal attachments combined with buccal pressure ridges. Biomechanical analysis quantified tooth displacement and stress distribution across tooth roots and periodontal ligament.

resultsGroups A-D exhibited significant buccal inclination in premolars and first molars, while second molar expansion remained limited. In contrast, Group E demonstrated a restricted expansion pattern. Regarding attachment position, palatal attachments (Group C) generated greater crown displacement in the mid-posterior segment (second premolar: 0.058 mm; first molar: 0.042 mm) compared to buccal attachments (Group B). Among the five groups, the buccal attachments combined with palatal pressure ridges (Group D) demonstrated superior biomechanical performance, achieving the greatest first molar expansion (0.057 mm) and favorable torque control (first molar: 3.42°/mm; second molar: 2.96°/mm). Notably, palatal attachments (Groups C and E) induced significantly higher von Mises stresses on the roots.

conclusionsMaxillary arch expansion with clear aligners is primarily achieved by buccal inclination of the posterior teeth. The configuration combining buccal attachments with palatal pressure ridges demonstrates biomechanical advantages, including enhanced crown displacement, better torque control, and favorable stress distribution.

Indexed as

Dental ArchFinite Element AnalysisMaxillaOrthodontic Appliances, RemovablePalatal Expansion TechniqueBicuspidBiomechanical PhenomenaDental Stress AnalysisHumansImaging, Three-DimensionalMolarOrthodontic Appliance DesignPeriodontal LigamentPressureStress, MechanicalTooth RootAttachmentClear alignerFinite element analysisMaxillary arch expansionPressure ridge

Identifiers

PMID41729442
PMCPMC12929728

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.