Comparison of Modified Vacuum-formed Retainers Versus Hawley Retainer

Comparison of Relapse Arch Width in Modified Vacuum Formed Retainers Covering the Palate Versus Hawley Retainer: A Prospective Randomized Control Trial

Sponsors

Lead Sponsor: National University of Malaysia

Source National University of Malaysia
Brief Summary

This study will focus on the relapse of arch width in two types of retention regimes, which are modified vacuum-formed retainers and Hawley type retainers in patients after fixed appliance treatment. This will subsequently be of valuable information for clinicians in choosing the appropriate type of retainers after removal of their fixed appliances. This is because the modified vacuum-formed retainers will be significantly cheaper, quicker and easier to fabricate.

Detailed Description

Relapse is inevitable in orthodontic treatment. Teeth will want to return to their original position after fixed appliances are removed. Regardless with or without fixed appliances, changes and physiological relapse will still occur due to time and age changes. This is why retention is a crucial part of orthodontic treatment, where it would aim to maintain the corrections achieved after orthodontic treatment.

Literature regarding retainers is quite substantial, where a recent Cochrane review was published comparing the different types of retainers. However, the evidence is lacking in terms of comparison of arch width relapse between modified vacuum-formed retainers and Hawley retainers specifically in expansion cases.

This study aims to compare the relapse in arch width in expansion cases with modified vacuum-formed retainers with palatal coverage versus Hawley type retainers in Unit Ortodontik Universiti Kebangsaan Malaysia (UKM), Klinik Pakar Ortodontik Klinik Kesihatan Bandar Botanik and Unit Pakar Ortodontik Klinik Pergigian Sungai Chua patients. Although other types of modified vacuum-formed retainers effective for maintaining palatal expansion have been described, these retainers require a wire outlining the Cementoenamel junction of the teeth palatally. This technique requires the experience of the technician, is at a higher cost and requires more lab time. The modified retainer that investigators described in this study would be as efficient and as quick as the normal vacuum-formed retainers, which would usually take a couple of hours to make (same day or next day fit). The present practice at all 3 locations constructs Hawley and normal VFR retainers for all orthodontic patients. There are technicians and laboratory facilities to construct normal VFR as well as Hawley retainer. The only difference between modified and normal vacuum formed retainer is the outline of the retainers where the technician would trim the retainer, where it would cover the hard palate. Therefore it is only the location of trimming that is different using the same special trimming appliances for normal VFRs.

A number of subjects who fulfil the criteria will be invited to participate in this study. The study will involve arch width analysis using study models pre, post-debond, 3 months review post-debond, and 6 months review post-debond. All data will be analyses using Statistical Package for Social Sciences (SPSS). The arch width of subjects post-fixed appliances will be compared. Most studies compare the arch width, as well as lower incisor irregularity in evaluating relapse in different groups of retainers. However, there are currently no randomized control trials comparing expansion cases of Hawley vs vacuum-formed retainers, hence why this study will be conducted.

The investigators expect to see no difference between the modified vacuum formed retainer and Hawley retainer in terms of maintaining arch expansion post-orthodontic treatment. This would, therefore, mean that there would be a simpler method and would be a suitable more cost-effective alternative as compared to constructing Hawley retainers or adding a palatal wire on the vacuum-formed retainers.

Overall Status Recruiting
Start Date January 24, 2019
Completion Date August 2020
Primary Completion Date August 2020
Phase N/A
Study Type Interventional
Primary Outcome
Measure Time Frame
Arch width T0 (at debond)-T1 (3-month post-debond)-T2 (6-month post-debond)
Enrollment 32
Condition
Intervention

Intervention Type: Device

Intervention Name: Modified vacuum-formed retainer covering the palete

Description: The modified vacuum-formed retainer is made where it would cover the hard palate to the second molars. The only difference in constructing this modified VFR when compared to the normal VFR would be the outline which would be trimmed by the technician.

Arm Group Label: Modified vacuum-formed retainer covering the palate

Intervention Type: Device

Intervention Name: Hawley retainer

Description: Standard retention regime for patients with arch expansion. Patients will be instructed to wear the retainer 24 hours during the study period.

Arm Group Label: Hawley retainer

Eligibility

Criteria:

Inclusion Criteria:

1. Patients who are at least 13 years old at time of debond.

2. Treatment plan of extraction or non-extraction followed by straight wire appliances in the upper arch only or both arches

3. Undergone expansion treatment in the upper arch causing an arch width increase of 3-10mm, either using a Quadhelix, Rapid Maxillary Expansion, expansion with archwires, or URA with midline screw. Patients' interarch measurements at the time of debond will be compared with their interarch measurements using the pre-treatment model available at the clinic.

4. No chronic medical conditions

Exclusion Criteria:

-

Gender: All

Minimum Age: 13 Years

Maximum Age: N/A

Healthy Volunteers: Accepts Healthy Volunteers

Overall Official
Last Name Role Affiliation
DR. ASMA ASHARI Principal Investigator National University of Malaysia
Overall Contact

Last Name: DR. ASMA ASHARI

Phone: +601922208440

Email: [email protected]

Location
Facility: Status: Contact:
Unit Pakar Ortodontik Klinik Pergigian Sungai Chua | Kajang, Selangor, 43000, Malaysia Recruiting DR. YEOH CHEW KIT +60163114942
Klinik Pakar Ortodontik Klinik Kesihatan Bandar Botanik | Klang, Selangor, 42000, Malaysia Recruiting DR. MALATHI DEVA TATA +60172350711
Orthodontic Specialist Clinic | Kuala Lumpur, 50300, Malaysia Recruiting DR. ASMA ASHARI +60192228440 [email protected]
Location Countries

Malaysia

Verification Date

June 2020

Responsible Party

Type: Principal Investigator

Investigator Affiliation: National University of Malaysia

Investigator Full Name: ASMA ASHARI

Investigator Title: Principal Investigator

Keywords
Has Expanded Access No
Number Of Arms 2
Arm Group

Label: Hawley retainer

Type: Active Comparator

Description: Standard retention regime for patients with arch expansion. Patients will be instructed to wear the retainer 24 hours during the study period.

Label: Modified vacuum-formed retainer covering the palate

Type: Experimental

Description: The modified vacuum-formed retainer is designed to cover the palate. It is cheaper, easier to fabricate and more esthetic. Patients will be instructed to wear the retainer 24 hours during the study period.

Patient Data No
Study Design Info

Allocation: Randomized

Intervention Model: Parallel Assignment

Primary Purpose: Treatment

Masking: Single (Outcomes Assessor)

Source: ClinicalTrials.gov