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Effect of Clear Aligner Attachment Size on Extrusion of Maxillary Lateral Incisors

Effect of Clear Aligner Attachment Size on Extrusion of Maxillary Lateral Incisors

Status
Completed
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06814262
Enrollment
28
Registered
2025-02-07
Start date
2025-03-31
Completion date
2026-06-01
Last updated
2026-06-08

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Orthodontic Appliance Complication

Keywords

Extrusion of Maxillary Lateral Incisors, Clear Aligner Attachment

Brief summary

Orthodontic treatment has been revolutionized by clear aligner therapy, offering patients a more esthetic and comfortable alternative to traditional braces. In 1999, Align Technology introduced Invisalign. As Invisalign has increased in popularity and demand over the past two decades, clinical trials have shed light on the efficacy of Invisalign treatment. there have been changes in the Invisalign protocol such as introduction of SmartForce features in 2008, such as optimized attachments as well as the implementation of SmartTrack aligner material in 2011. Compared to conventional fixed orthodontic appliances, Invisalign cannot be adjusted on a visit-to visit basis. If ideal tooth movement has not been achieved after completion of the first sequence of aligners, additional trays, known as refinement trays, are required.

Detailed description

There are various expert theories regarding the most effective methods of extrusion and multiple studies performed in vitro to evaluate the efficacy of different attachment types on the extrusion of lateral incisors, however only one in vivo clinical trial exists. There is a need for more randomized clinical trials that evaluate the effectiveness of different attachment designs for achieving optimal extrusion of lateral incisors. By determining the most effective attachment size for maxillary lateral incisor extrusion, this study can help improve treatment outcomes for orthodontic treatment with clear aligners and serve as a guide to assist clinicians in selecting the most effective attachment design.

Interventions

DEVICECorresponding treatment order in the prescription with Align Technology

Treating orthodontist placing the corresponding order in the prescription with Align Technology.

DEVICESuperimposition of final and initial positions of lateral incisors: Predicted model

Superimposition of final and initial positions of lateral incisors, two superimpositions will be completed. The pretreatment model will be superimposed with the predicted final model to establish the predicted movement of the maxillary lateral incisors

DEVICESuperimposition of final and initial positions of lateral incisors: Gingivally beveled 1x1x3mm aligners

Superimposition of final and initial positions of lateral incisors, two superimpositions will be completed. The pretreatment model (Gingivally beveled 1x1x3mm aligners) will be superimposed with the posttreatment model to establish the actual movement of the maxillary lateral incisor.

DEVICESuperimposition of final and initial positions of lateral incisors: Gingivally beveled 1x1x4mm aligners

Superimposition of final and initial positions of lateral incisors, two superimpositions will be completed. The pretreatment model (Gingivally beveled 1x1x4mm aligners) will be superimposed with the posttreatment model to establish the actual movement of the maxillary lateral incisor.

DEVICESuperimposition of final and initial positions of lateral incisors: Gingivally beveled 1x1x5mm aligners

Superimposition of final and initial positions of lateral incisors, two superimpositions will be completed. The pretreatment model (Gingivally beveled 1x1x5mm aligners) will be superimposed with the posttreatment model to establish the actual movement of the maxillary lateral incisor.

Sponsors

Virginia Commonwealth University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Intervention model description

Randomized Controlled Trial

Eligibility

Sex/Gender
ALL
Age
12 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Patients treated with either Comprehensive Invisalign or Invisalign Teen treatment * The maxillary arch has less than 6 mm of crowding or spacing * Maxillary lateral incisors have a minimum of 0.3 mm of extrusion prescribed in the Tooth Movement Table on the Invisalign ClinCheck for the first set of aligners * Maxillary lateral incisors within a normal range of bucco-lingual inclination * Patients 12 years of age or older and either the patient or legal guardian are able to give consent * Patients confirm good compliance throughout the study period

Exclusion criteria

* Patients do not complete all aligners in the first phase as prescribed * Poor compliance recorded for aligner wear * Restorations placed or oral surgery completed prior to final scan * Midcourse intervention to improve tracking such as a bootstrap * Maxillary lateral incisors not tracking and noted by minimum of 1 mm of aligner material incisally displaced when aligner fully seated * Treatment plans include surgery or extractions * Maxillary lateral incisors with pathology and restorations * Missing teeth other than third molars * Patients with anterior crossbite

Design outcomes

Primary

MeasureTime frameDescription
Determine which of three different attachment sizes offers more predictable extrusion of maxillary lateral incisors in subjects treated with clear aligners comparedbaseline until the clear aligner treatment is completed at 20 to 25 weeksThe aim of this prospective, randomized controlled trial is to determine which of three different attachment sizes (gingivally beveled 1x1x3 mm, gingivally beveled 1x1x4 mm, or gingivally beveled 1x1x5 mm) offers more predictable extrusion of maxillary lateral incisors in patients treated with clear aligners compared to control.

Secondary

MeasureTime frameDescription
Evaluate the accuracy of ClinCheck softwarebaseline until the clear aligner treatment is completed at 20 to 25 weeksTo evaluate the accuracy of ClinCheck software in predicting the three-dimensional final position of the lateral incisor following extrusion using the attachment designs tested.

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORSteven Lindauer

Virginia Commonwealth University

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Jun 9, 2026