Efficacy and Cost-effectiveness of Orthodontic Retention Protocols

Not Applicable

• Conditions: Orthodontic Relapse
• Interventions: Device: fixed retainer; Device: removable retainer

• Registration Number: NCT05121220
• Lead Sponsor: Poliklinika Orthonova

Brief Summary

Objective is to assess changes of dentition and periodontium, and hygiene in retention after the end of the active phase of orthodontic treatment, and relationship with gender, type of retention appliance, pre-therapeutic condition of dentition and duration of active phase of treatment.

Detailed Description

A total of 152 subjects will be recruited and randomly assigned into three groups. First group will have a square 8-stranded 0.673x0.268 mm retainer wire bonded in mandibular teeth after completing the active phase of comprehensive orthodontic treatment with fixed appliances. Retainer will be bonded on lingual site canine to canine on each tooth. Second group will have a round 6-stranded 0.40 mm retainer in mandible. Third group will be without fixed retainer, only with thermoplastic vacuum-formed removable Essix retainer in mandible.

Subjects will be examined before orthodontic treatment (T0), upon completion of treatment (T1), six months in retention (T2), two years (T3) and three years in retention (T4). Changes in intercanine width, relapse (unexpected tooth movements), retainer failure, accumulation of biofilm, calculus and gingivitis will be assessed.

Study Timeline

• Study Start: 2020-11-15
• Study First Submitted: 2021-10-02
• Study First Submitted QC: 2021-11-03
• Study First Posted: 2021-11-16
• Status Verified: 2022-05
• Last Update Submitted: 2022-05-03
• Last Update Posted: 2022-05-09
• Primary Completion: 2022-11-15
• Study Completion: 2023-11-15

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 152

Inclusion Criteria

finished orthodontic treatment, participants must have all permanent teeth

Exclusion Criteria

hypodontia, missing teeth

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
fixed mandibular lingual round retainer 0.40 mm	fixed retainer	0.40 mm round 6-stranded wire (Forestadent, Germany) will be bonded on 6 mandibular frontal teeth, canine to canine on each tooth using Filtek flowable composite (Ivoclar Vivadent, Lichtenstein) and Multilink adhesive (3M, USA).
fixed mandibular lingual rectangular retainer 0.673 x 0.268 mm	fixed retainer	0.673 x 0.268 mm 8-stranded wire Bond A Braid (Reliance Orthodontic Products, USA) will be bonded in mandible canine to canine on each tooth using Filtek flowable composite (Ivoclar Vivadent, Lichtenstein) and Multilink adhesive (3M, USA).
removable mandibular retainer	removable retainer	Group without fixed retainer will be wearing removable thermoplastic vacuum-formed Essix retainer

Primary Outcome Measures

Name	Time	Method
severity of relapse (unexpected tooth movement in mandibular frontal area) at 2 years	2 years	the unabbreviated scale title: Little Irregularity Index (used to measure the crowding)- numerical rating scale in millimeters the minimum and maximum values: 0,10 higher scores mean a worse outcome lower scores mean a better outcome
severity of relapse (unexpected tooth movement in mandibular frontal area) at 3 years	3 years	the unabbreviated scale title: Little Irregularity Index (used to measure the crowding)- numerical rating scale in millimeters the minimum and maximum values: 0,10 higher scores mean a worse outcome lower scores mean a better outcome
incidence of retainer failure (debonding, breakage) at 3 years	3 years	percentage of cases with at least one fixed retainer failure, the minimum and maximum values 0%,100% higher scores mean a worse outcome, lower scores mean a better result
severity of relapse (unexpected tooth movement in mandibular frontal area) at 1 year	1 year	the unabbreviated scale title: Little Irregularity Index (used to measure the crowding)- numerical rating scale in millimeters the minimum and maximum values: 0,10 higher scores mean a worse outcome lower scores mean a better outcome
extent of biofilm accumulation at 3 years	3 years	the unabbreviated scale title: Silness and Loe Plaque Index-ratio of measuring sites in mandibular central sextant; the minimum and maximum values 0%,100%, higher scores mean a worse outcome, lower scores mean a better result
incidence of retainer failure (debonding, breakage) at 2 years	2 years	percentage of cases with at least one fixed retainer failure, the minimum and maximum values 0%,100% higher scores mean a worse outcome, lower scores mean a better result
extent of biofilm accumulation at 2 years	2 years	the unabbreviated scale title: Silness and Loe Plaque Index-ratio of measuring sites in mandibular central sextant; the minimum and maximum values 0%,100%, higher scores mean a worse outcome, lower scores mean a better result

Secondary Outcome Measures

Name	Time	Method
incidence of intercanine width change	3 years	percentage of cases with intercanine width change, the minimum and maximum values 0%,100% higher scores mean a worse outcome, lower scores mean a better result
extent of calculus accumulation at 2 years	2 years	the unabbreviated scale title: Calculus Surface Index (CSI)-ratio of measuring sites in mandibular central sextant; the minimum and maximum values 0%,100%, higher scores mean a worse outcome, lower scores mean a better outcome
extent of calculus accumulation at 3 years	3 years	the unabbreviated scale title: Calculus Surface Index (CSI)-ratio of measuring sites in mandibular central sextant; the minimum and maximum values 0%,100%, higher scores mean a worse outcome, lower scores mean a better outcome
changes of intercanine width	2 years, 3 years	the unabbreviated scale title: intercanine width change in millimeters, the minimum and maximum values 0,5, higher scores mean a worse outcome, lower result mean a better outcome

Trial Locations

Locations (1)

Poliklinika Orthonova; 🇭🇷 Zagreb, Croatia