Clinical Effectiveness of Bonded Versus Vacuum-formed Retainers

University of Sao Paulo

Status: Completed

Conditions: Relapse

Treatments: Device: Vacuum-formed Retainer; Device: V-bend Bonded Retainer

Study type: Interventional

Funder types: Other

Identifiers

NCT04847323

001

22092919.7.0000.5417

Details and patient eligibility

About

The purpose of the study was to compare the clinical effectiveness of bonded versus vacuum-formed retainers regarding their retention capacity; periodontal health; survival rates; and patients' perception after 12 months of removal of fixed appliances.

The null hypotheses considered that there was no differences between the retainers in relation to the aspects evaluated.

Full description

This single-center randomized controlled trial was performed at the Department of Orthodontics, Bauru Dental School, University of São Paulo, Brazil.

A total of 50 patients completing orthodontic treatment were recruited. The patients were prospectively and randomly allocated into two groups. The first group consisted of 25 patients with canine-to-canine V-bend bonded retainers; while the second group comprised 25 patients with vacuum-formed retainers. In both groups, the same retainers were installed in the maxillary and mandibular arches.

Patients were evaluated at deboning (T0), after 3 months (T1), 6 months (T2), and 12 months (T3). In each appointment, digital models were obtained and the other clinical variables were evaluated. The primary and secondary outcomes were compared between retainers in the time-points evaluated.

Enrollment: 50 patients

Sex: All

Ages: 12+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Patients with the proper completion of orthodontic treatment and correction of the initial malocclusion.
• Acceptable oral hygiene (assessed through clinical examination).
• Presence of all teeth up to the second molars.
• Clinically acceptable teeth alignment.

Exclusion criteria

• Patients with any systemic condition that may have an influence on periodontal health.
• Patients with facial deformities.
• Initial malocclusion that required extreme corrections, large transverse expansions or orthognathic surgery.
• History of periodontal diseases.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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50 participants in 2 patient groups

V-bend Bonded Retainer

Active Comparator group

Description:

The V-bend retainer was bonded in the lingual surface of the anterior teeth. The retainer was constructed using 0.024" stainless steel wires. Differently from the conventional bonded retainers, this retainer presents V-bends in the sagittal direction, parallel to the occlusal plane in each interproximal contact point of the incisors and canines. The retainers was bonded after adequate etching with phosphoric acid and application of adhesive with a low viscosity resin.

Treatment:

Device: V-bend Bonded Retainer

Vacuum-formed Retainer

Active Comparator group

Description:

The removable Vacuum-formed retainers were made of acetate 1mm thickness. They were made at the same appointment of debonding using plaster models. The patients were instructed to use the retainers only during nights.

Treatment:

Device: Vacuum-formed Retainer