Comparing different types of retainers for maintaining lower incisor alignment

Retentive Capacity of Bonded Retainer Versus Vacuum-formed and Combined Bonded-vacuum Retainers: A Randomized Controlled Clinical Trial

Not applicable Interventional Cairo University · NCT06476574

This study is testing which type of retainer—fixed, vacuum-formed, or a mix of both—works best to keep lower front teeth straight after braces.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment45 (estimated)
Ages18 Years to 35 Years
SexAll
SponsorCairo University Academic / other
Locations1 site (Cairo)
Trial IDNCT06476574 on ClinicalTrials.gov

What this trial studies

This study aims to evaluate the effectiveness of fixed retainers, vacuum-formed retainers, and a combination of both in maintaining the alignment of lower incisors after non-extraction orthodontic treatment. Participants will undergo a debonding process, followed by the removal of adhesive remnants and polishing of enamel surfaces. They will then be randomly assigned to one of the retainer types, with their periodontal health monitored throughout the study. The goal is to determine which retainer type offers the best retention and patient satisfaction.

Who should consider this trial

Good fit: Ideal candidates are adult patients who have completed non-extraction orthodontic treatment and maintain good oral hygiene.

Not a fit: Patients with systemic diseases affecting periodontal health, smokers, or those with poor oral health may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide insights into the most effective retainer type for preventing orthodontic relapse, improving long-term outcomes for patients.

How similar studies have performed: While there is limited evidence on the effectiveness of different retainer types, this study aims to fill a gap in knowledge, making it a novel approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Adult patients
* Finished non-extraction orthodontic treatment
* Full set of permanent dentition (excluding third molars).
* Good oral hygiene
* No restorations on lower anterior teeth or morphologic crown anomalies.
* Little's irregularity index score 0

Exclusion Criteria:

* Systemic disease or drugs affecting periodontal health.
* Smokers
* Poor oral health that precludes orthodontic treatment (presence of caries, active white spots,or periodontal diseases)

Where this trial is running

Cairo

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Orthodontic RetainerFixed Orthodontic RetainerOrthodontic RelapseEssix RetainerVacuum-formed RetainerDual Retention Protocol
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.