Evidence map›Paper›PMID 42189428›Full record

ArticleProgress in orthodontics2026

Three-dimensional crown-root movement in first premolar extraction cases treated with two clear aligner systems based on different materials: a retrospective cohort study.

Luyao Qu, Runzhe Fang, Ruomei Li, Zitong Yang, Yixin Li, Xuehui Chen, Boxi Chen, Jian Wang, Lingjun Yuan, Lunguo Xia and 1 more

Abstract readComparative Study
In one paragraph

Article in Progress in orthodontics, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0cells of the map it votes in
0citing papers in PubMed
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1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

11 authors.

Luyao QuDepartment of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Runzhe FangDepartment of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Ruomei LiDepartment of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Zitong YangDepartment of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Yixin LiDepartment of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Xuehui ChenDepartment of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Boxi ChenDepartment of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Jian Wangdepartment of stomatology, Fengcheng hospital of Fengxian District, Shanghai, China.
Lingjun YuanDepartment of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China. yuanlingjun00@126.com.
Lunguo XiaDepartment of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China. xialunguo@hotmail.com.
Bing FangDepartment of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China. fangbing@sjtu.edu.cn.

Funding

the Ministry of Science and Technology of the People's Republic of China 2022YFC2405904
6 · The paper itself

Abstract

aimsTo quantify and compare the three-dimensional (3D) deviations of crown and root movements produced by two clear aligner systems based on different materials-SmartTrack (ST) and MasterControl S (MCS)-in first premolar extraction cases using a 3D crown-root registration approach.

methodsThis retrospective cohort study included 29 patients (58 dental sides) treated with ST (n = 15) or MCS (n = 14). Pretreatment (T0) CBCT images were integrated with T0 and post-treatment (T1) intraoral scans and superimposed using palatal rugae as reference structures. Linear mixed-effects models (LMM) were applied to estimate between-material differences while adjusting for age, sex, and standardized planned movement magnitude. Estimates are reported with 95% confidence intervals (CI).

resultsThe two systems demonstrated no statistically significant difference in deviation in sagittal crown retraction of the maxillary central incisor (U1) (ST: 1.25 (1.30) mm; MCS: 2.13 (1.82) mm; LMM difference: -  0.81 mm; 95% CI  - 1.89-0.28; P = 0.145). MCS demonstrated smaller deviation in sagittal root positioning for the second premolar (U5) (difference: 1.07 mm; 95% CI 0.21-1.93; P = 0.015) and first molar (U6) (difference: 1.04 mm; 95% CI 0.13-1.94; P = 0.025). ST showed improved control of U5 axial inclination (difference: 3.33°; 95% CI 0.27-6.39; P = 0.033) and torque (difference: 3.04°; 95% CI 0.08 to 6.00; P = 0.044). Both systems exhibited a consistent "roller-coaster effect", with no significant difference in unplanned U1 extrusion (difference: 0.14 mm; 95% CI  - 0.73-1.02; P = 0.747).

conclusionsThe biomechanical performance of clear aligner systems appears to vary depending on tooth position and movement vector. SmartTrack demonstrated better control of premolar angulation and torque, whereas MasterControl S showed closer agreement with the planned sagittal root position.

Indexed as

BicuspidOrthodontic Appliance DesignTooth CrownTooth ExtractionTooth Movement TechniquesTooth RootAdolescentChildCone-Beam Computed TomographyFemaleHumansImaging, Three-DimensionalMaleRetrospective StudiesClear alignersFirst premolar extractionLinear mixed-effects modelsMasterControl SSmartTrackThree-dimensional tooth movement

Identifiers

PMID42189428
PMCPMC13212943

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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.