Vacuum-formed Retainer Versus Bonded Retainer to Prevent Relapse After Orthodontic Treatment

Region Gävleborg

Status: Completed

Conditions: Retention; Orthodontics

Treatments: Procedure: Alginate impression; Device: Essix retainer maxilla; Device: CTC retainer; Device: Essix retainer mandible; Other: Questionnaire

Study type: Interventional

Funder types: Other

Identifiers

NCT03070444

CFUG-557411

Details and patient eligibility

About

The purpose of this trial is to evaluate and compare stability after orthodontic treatment with an Essix retainer and a bonded cuspid-to-cuspid retainer (CTC), respectively in the mandibular arch and longitudinally follow these patients over time up to 5 years. The patients' perceptions of the two methods are also evaluated with questionnaires during the follow-up period.

A further aim of this study is to analyze the relationship between diagnosis, treatment outcome, treatment time, age at start of treatment and stability with an Essix retainer in the maxilla.

The null hypotheses are:

• that there is no difference in retention capacity between Essix retainer and cuspid-to-cuspid retainer
• that there is no difference in patients' perception between Essix retainer and cuspid-to-cuspid retainer
• that there is no difference in retention capacity for Essix retainer in the maxilla concerning diagnosis before treatment, treatment outcomes, treatment time and age at start of treatment

Full description

The study is conducted at the Orthodontic Clinic, Gävle, Sweden and consists of 104 patients. All patients are treated with fixed appliances in the upper and lower jaw (standard .022 straight wire), both with and without extractions. The patients are randomized into two groups with 52 patients in each group (Group A: cuspid-to-cuspid retainer, Group B: Essix retainer).

Dental cast are obtained at the debond appointment (T1) and at the follow-up controls after six months (T2), 18 months (T3) and 60 months (T4) for both groups.

At the visit two weeks in retention and at the follow-up visits after 6, 18 and 60 months the patients assess questionnaires in order to evaluate their experience of retention with the retention device.

Enrollment: 104 patients

Sex: All

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Patients treated with fixed appliances in both the maxilla and the mandible

Exclusion criteria

• Rapid Maxillary Expansion (RME) for patients with severe transversal malocclusion
• Treatment with segmented appliances
• Patients with craniofacial anomalies and patients requiring orthognatic surgery
• Patients with missing mandibular incisor

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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104 participants in 2 patient groups

Group A: CTC retainer + Essix retainer

Experimental group

Description:

The CTC is bonded directly after debonding. The Essix retainer maxilla is handed out to the patient the same day after removal of fixed appliances. Alginate impressions are taken at the follow-up visits. Questionnaires are completed at the follow-up visits.

Treatment:

Procedure: Alginate impression

Device: CTC retainer

Device: Essix retainer maxilla

Other: Questionnaire

Group B: Essix retainer + Essix retainer

Active Comparator group

Description:

The Essix retainer maxilla and Essix retainer mandible are handed out to the patient the same day after removal of fixed appliances. Alginate impressions are taken at the follow-up visits. Questionnaires are completed at the follow-up visits.

Treatment:

Procedure: Alginate impression

Device: Essix retainer mandible

Device: Essix retainer maxilla

Other: Questionnaire