The Effect of Full Versus Partial Coverage Thermoformed Retainers in Dual Retention With a Lower Bonded Retainer, on Periodontal, Orthodontic, and Patient-Reported Outcomes

Official title

The Effect of Full Versus Partial Coverage Thermoformed Retainers in Dual Retention With a Lower Bonded Retainer, on Periodontal, Orthodontic, and Patient-Reported Outcomes: A Randomised Controlled Trial

Overview

After braces are removed, teeth may move back toward their original positions. Retainers are used to help keep teeth straight after orthodontic treatment. This study compares two types of clear removable retainers used together with a fixed wire retainer behind the lower front teeth. One retainer covers the entire inner surface of the teeth (full coverage), while the other covers only part of the inner surface (partial coverage). The purpose of this study is to find out whether the two retainer designs differ in their effects on gum health, comfort, retainer breakages, stability of the orthodontic correction, comfort, and compliance. The findings from this study may help orthodontists choose the most suitable retainer design for future patients. Participants in this study will receive a fixed wire retainer on the lower front teeth and upper and lower clear removable retainers. They will be randomly assigned to receive either the full coverage or partial coverage lower retainer. Participants will attend follow-up visits at 1 month, 3 months, and 6 months after starting retainer wear. At these visits, the orthodontist will examine the teeth, gums, and retainers, and participants will complete a short questionnaire about their experience wearing the retainer. This study excluded participants who are pregnant or breastfeeding within the first 6 months, have uncontrolled medical conditions or gum disease, smoke or vape, require a Hawley retainer instead of a clear retainer, or have missing front teeth or certain jaw conditions. Participants may benefit from receiving retainers, oral hygiene care, and regular monitoring of their teeth and gum health at no additional cost. Participants will also receive an oral care kit during the debond appointment and at the 3-month and 6-month review visits. Possible risks include breakage of the retainers, which may require repair or replacement, gum problems if oral hygiene is not maintained, and slight tooth movement despite retainer use. If gum problems develop, appropriate cleaning and referral for further treatment may be provided. Replacement retainers required during the study period will be provided free of charge.

Detailed description

Vivera retainers will be the only thermoformed retainers used throughout this study.

Interventions

• Device Partial coverage vivera retainer
  A removable lower retainer (Vivera retainer) with partial coverage design which covers part of the inside surface of lower teeth excluding the fixed bonded retainer
• Device Full coverage Vivera retainer
  A removable lower retainer (Vivera retainer) with full coverage design which covers the entire inside surface of lower teeth including the fixed bonded retainer

Primary outcome measures

• Full mouth plaque score [Time frame: baseline, 1 month, 3 months and 6 months]
• Full mouth bleeding on probing score [Time frame: Baseline, 1 month, 3 months and 6 months]
• Periodontal probing depth of lower anterior teeth [Time frame: baseline, 1 month, 3 months and 6 months]
• Gingival recession on lower anterior teeth [Time frame: Baseline, 1 month, 3 months and 6 months]
• Integrity of clear retainer [Time frame: 3 months and 6 months]
• Breakages of fixed bonded retainers [Time frame: 1 month, 3 months, 6 months]

Secondary outcome measures (3)

• Stability of lower anterior teeth [Time frame: Baseline, 3 months, 6 months]
• Quality of Life in Patients Wearing Orthodontic Retainers [Time frame: 3 months and 6 months]
• Patient's compliance [Time frame: 3 months and 6 months]

Eligibility criteria

Inclusion criteria

• Aged over 18 years.
• Controlled systemic diseases and conditions.
• Probing pocket depth ≤ 3 mm
• Bleeding on probing < 10 per cent
• Full mouth plaque scores of less than 20 per cent
• Just completed active orthodontic treatment involving lower arch
• Patient consent to dual retention in the lower arch

Exclusion criteria

• Require a Hawley retainer in the lower arch.
• Patients in retention phase requiring replacement of retainers
• Uncontrolled systemic disease, including chronic or metabolic diseases.
• Pregnant or lactating mothers within six months postpartum.
• Taking medications that affect gingival health and architecture.
• Have one or more missing anterior teeth.
• Have congenital craniofacial deformities and syndromes, including cleft lip and/ or palate
• Cigarette or vape smokers

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Open label

Primary purpose

Treatment

Study locations

Malaysia · 1 center

• Faculty of Dentistry, Universiti Malaya — Kuala Lumpur

Identifiers

NCT: NCT07669129 · DF CD2609/0046 (P)

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗