Morphological Changes of Removable Orthodontic Retainers During the Use

NCT06283823 | Completed

• 1 other identifier: 41821
• Study Type: observational
• Target: 41
• Locations: 1 country
• Sites: 1

Brief Summary

The retention is one of the stages of orthodontic treatment that aims to keep the teeth in the correct positions after orthodontic treatment. Without a retention phase, there is a tendency for the teeth to return to their initial position (relapse). To prevent relapse, at the end of orthodontic therapy the use of retaining devices to keep the teeth in their ideal position is required. The aim of the study is to analyse whether intraoral aging of removable retention devices can lead to morphological or dimensional changes, and whether or not these changes are related to orthodontic relapse, expressed as a change in the Peer Assessment Rating (PAR) index. The PAR index is an index that allows us to evaluate the relapse after orthodontic treatment. In this study the PAR index will be measured at the start of the retention period (T0), at the three-months follow-up (T1) and at the six months follow-up (T2). In particular, two types of thermoformed retainers with different cutouts will be evaluated to determine whether the presence of higher margins in a type of retainers allows to maintain greater stability over time and, therefore, to confer a mechanical and clinical advantage.

Conditions

Orthodontic Retainer

Keywords

orthodontic; retainer; stability; thermoformable retainer

Outcome Measures

Primary Outcomes (2)

• Peer Assessment Rating (PAR) index

  The PAR index will be measured on digital casts to evaluate the amount of alignment relapse.

  3 years

• Volumetric superimposition of digital models

  Digital models of pre- and post-usage thermoformed retainers will be superimposed and the distance between the two digital models will be measured

  3 years

Secondary Outcomes (1)

• Thickness

  3 years

Study Arms (2)

Retainer with high margins

Thermoformed retainers with modified cutout and high margins in the posterior region of the retainer

Device: Thermoformed orthodontic retainer

Retainer with low margins

Thermoformed retainer with conventional festooned cutout and low margins

Device: Thermoformed orthodontic retainer

Interventions

Thermoformed orthodontic retainer DEVICE

compare the outcome of the retaining phase of the orthodontic treatment with two different thermoformed retainers

Retainer with high margins; Retainer with low margins

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Probability Sample

Study Population

Undergraduate students

You may qualify if:

• young adult patients: 18-35 years;
• Caucasian ethnic group;
• good oral hygiene (evaluated by observing a plaque index \< 20% understood as the sum of the indices of the individual dental elements divided by the number of dental elements considered multiplied by 100);
• patients with normal occlusion Class I occlusion with slight overcrowding and PAR Index less than or equal to 10;
• patients who have received previous orthodontic treatment, with or without stripping;
• patients who have received previous orthodontic treatment with \< 20 orthodontic aligners;
• patients who currently use a thermoprinted mask as a restraint, or who do not use any restraint but who would like to receive one.

You may not qualify if:

• patients with chromosomal defects, specific neuropsychological disorder, epilepsy (1);
• patients with systemic diseases and comorbidities;
• bruxist patients;
• patients with hypertrophy of chewing muscles, occlusal parafunctions or joint disorders;
• patients with cognitive disabilities with IQ\<70;
• patients undergoing drug therapy.

Sponsors & Collaborators

• University of L'Aquila: lead

Study Sites (1)

University of L'Aquila

L’Aquila, Italy, 67100, Italy

Location

Related Publications (7)

• Bucci R, Rongo R, Levate C, Michelotti A, Barone S, Razionale AV, D'Anto V. Thickness of orthodontic clear aligners after thermoforming and after 10 days of intraoral exposure: a prospective clinical study. Prog Orthod. 2019 Sep 9;20(1):36. doi: 10.1186/s40510-019-0289-6.

  PMID: 31495908 BACKGROUND

• Saghaei M. Random allocation software for parallel group randomized trials. BMC Med Res Methodol. 2004 Nov 9;4:26. doi: 10.1186/1471-2288-4-26.

  PMID: 15535880 BACKGROUND

• Schuster S, Eliades G, Zinelis S, Eliades T, Bradley TG. Structural conformation and leaching from in vitro aged and retrieved Invisalign appliances. Am J Orthod Dentofacial Orthop. 2004 Dec;126(6):725-8. doi: 10.1016/j.ajodo.2004.04.021.

  PMID: 15592222 BACKGROUND

• Gerard Bradley T, Teske L, Eliades G, Zinelis S, Eliades T. Do the mechanical and chemical properties of InvisalignTM appliances change after use? A retrieval analysis. Eur J Orthod. 2016 Feb;38(1):27-31. doi: 10.1093/ejo/cjv003. Epub 2015 Mar 3.

  PMID: 25740599 BACKGROUND

• Lombardo L, Arreghini A, Maccarrone R, Bianchi A, Scalia S, Siciliani G. Optical properties of orthodontic aligners--spectrophotometry analysis of three types before and after aging. Prog Orthod. 2015;16:41. doi: 10.1186/s40510-015-0111-z. Epub 2015 Nov 18.

  PMID: 26582007 BACKGROUND

• Thickett E, Power S. A randomized clinical trial of thermoplastic retainer wear. Eur J Orthod. 2010 Feb;32(1):1-5. doi: 10.1093/ejo/cjp061. Epub 2009 Oct 14.

  PMID: 19828592 BACKGROUND

• Richmond S, Shaw WC, O'Brien KD, Buchanan IB, Jones R, Stephens CD, Roberts CT, Andrews M. The development of the PAR Index (Peer Assessment Rating): reliability and validity. Eur J Orthod. 1992 Apr;14(2):125-39. doi: 10.1093/ejo/14.2.125.

  PMID: 1582457 BACKGROUND

Study Officials

• Michele Tepedino

  University of L'Aquila

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: February 21, 2024
• First Posted: February 28, 2024
• Study Start: December 21, 2021
• Primary Completion: April 1, 2024
• Study Completion: September 30, 2024
• Last Updated: April 1, 2025

Record last verified: 2025-03

Locations

IT (1)