Evaluation of the Effect of Aligner Seaters on the Predictability of Tooth Movement in Clear Aligner Therapy.

July 22, 2026 updated by: Farah Alaa Hussein, University of Baghdad

Evaluation of the Effect of Aligner Seaters on the Predictability of Tooth Movement in Clear Aligner Therapy: A Randomized Clinical Trial

The goal of clinical trial is to know the role clear aligner seater. The main question it aims to answer is to evaluate the use of clear aligner seater on the effectiveness of clear aligner therapy by questioning the predictability of proposed treatment plan.

  • Group A (Regular-use group): Use chewy with the 1st insertion of each aligner sets for a day or a couple of days until the aligner seated well with no gap with the teeth. The patients will be instructed to bite on the chewy while the aligners are in position for few seconds.
  • Group B (customized-use group): In addition to the regular use of the chewy, the participants will be instructed to bite for few seconds while the aligners are in their mouth at bedtime on a daily bases.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Detailed Description

A single-operator, multi-center randomized controlled trial (RCT) with a 1:1 allocation ratio will be conducted among patients seeking orthodontic treatment with clear aligner therapy. The study will take place at the Postgraduate Orthodontic Clinic, College of Dentistry, University of Baghdad, Baghdad, Iraq. Eligible participants will be randomly assigned to one of two aligner seater (chewy) use protocols. To minimize inter-operator variability, all participants will be treated by the same orthodontist.

A standardized clinical protocol will be followed. Each participant will undergo extraoral and intraoral photography, intraoral scanning using the Medit i700 scanner (Medit Corp., Seoul, South Korea), and radiographic assessment including cone-beam computed tomography (CBCT) and lateral cephalometric radiography.

On the day of aligner insertion, gingival index and plaque index will be recorded. The teeth will be isolated and cleaned with a water-pumice slurry using a rubber polishing cup mounted on a low-speed handpiece. The enamel surfaces will be rinsed and dried with oil-free compressed air, followed by conventional acid etching with 37% phosphoric acid for 30 seconds. The etched surfaces will then be rinsed for 10 seconds according to the manufacturer's instructions and air-dried until a frosty white appearance is observed.

A universal adhesive (BISCO All-BOND UNIVERSAL, USA) will be applied to the etched enamel surfaces using a nylon brush, followed by gentle air thinning for 2 seconds with the air stream directed perpendicular to the enamel surface. Attachment templates will be filled with Neo Spectra™ ST Universal Composite (Dentsply Sirona), a nanohybrid composite material, and attachments will be bonded according to the aligner manufacturer's prescribed attachment positions. The composite will then be light-cured for 20 seconds.

Group A (Regular-use group): Participants will use the aligner seater during the initial insertion of each new aligner for one to two days, or until the aligner is fully seated without visible gaps. Participants will be instructed to bite on the aligner seater for a few seconds while the aligner is in place.

Group B (Customized-use group): In addition to the regular-use protocol described for Group A, participants will be instructed to bite on the aligner seater for a few seconds each night at bedtime throughout the study period.

All participants will receive standardized written instructions regarding clear aligner care and the manufacturer's recommendations. A study-specific questionnaire will be completed to assess pain during treatment. Participants will attend follow-up visits every 30 days (after every three aligners), during which gingival index, plaque index, intraoral photographs, digital intraoral scans, and questionnaire data will be collected. Participants will also be instructed to contact the treating orthodontist immediately if attachment loss occurs.

Participants will be followed for four months.

Study Type

Interventional

Enrollment (Estimated)

34

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Iraq
      • Baghdad, Iraq, 10047
        • University of Baghdad/ collage of Dentistry

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Male and female participants.
  • Age between 18 and 45 years.
  • Mild to moderate crowding or spacing.
  • ANB angle between 1° and 5°.
  • Planned for non-extraction clear aligner treatment.
  • Willing and able to provide written informed consent and comply with the study protocol.

Exclusion Criteria:

  • Craniofacial syndromes (e.g., cleft lip and/or palate) or other congenital craniofacial anomalies.
  • Severe crowding.
  • Signs and/or symptoms of temporomandibular disorders (TMD).
  • Previous orthodontic treatment.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Regular-use of chewy group
Use chewy with the 1st insertion of each aligner sets for a day or a couple of days until the aligner seated well with no gap with the teeth. The patients will be instructed to bite on the chewy while the aligners are in position for few seconds
Device: Aligner seater
Participants use silicone aligner seaters during clear aligner therapy. The study compares two different protocols of aligner seater use: regular use and customize use.
Experimental: Customized-use of chewy group
In addition to the regular use of the chewy, the participants will be instructed to bite for few seconds while the aligners are in their mouth at bedtime on a daily bases.
Device: Aligner seater
Participants use silicone aligner seaters during clear aligner therapy. The study compares two different protocols of aligner seater use: regular use and customize use.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Primary outcome measure
Time Frame: Four months
Tooth movement predictability will be assessed as the absolute difference between the prescribed and achieved tooth movement in linear (mm) and angular (degrees) measurements using three-dimensional digital model superimposition. Digital models will be analyzed using Geomagic Control X software.
Four months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Pain during clear aligner therapy
Time Frame: 1 hour, 6 hours, 2 days, 5 days, and 7 days after insertion of first aligner.
Pain intensity will be assessed using a Visual Analog Scale (VAS) questionnaire at 1 hour, 6 hours, 2 days, 5 days, and 7 days after insertion of first aligner.
1 hour, 6 hours, 2 days, 5 days, and 7 days after insertion of first aligner.
Periodontal health
Time Frame: Baseline and every monthly follow-up visit throughout the 4-month study period
Periodontal health will be assessed using the Bleeding on Probing (BOP) index and the Plaque Index (PI).
Baseline and every monthly follow-up visit throughout the 4-month study period

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of Baghdad

Investigators

  • Principal Investigator: Farah Alaa Hussein, B.D.S., University of Baghdad/ collage of Dentistry
  • Study Director: Hadeel Adel Al-lami, Ph.D orthodontics, University of Baghdad/ collage of Dentistry

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

February 16, 2026

Primary Completion (Estimated)

August 1, 2027

Study Completion (Estimated)

September 1, 2027

Study Registration Dates

First Submitted

June 22, 2026

First Submitted That Met QC Criteria

July 22, 2026

First Posted (Actual)

July 24, 2026

Study Record Updates

Last Update Posted (Actual)

July 24, 2026

Last Update Submitted That Met QC Criteria

July 22, 2026

Last Verified

July 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 1105425

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Malocclusions

Clinical Trials on Aligner seater

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Mozambique

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe