3D Comparison of Anterior Teeth Retraction and Anchorage Control Between En-masse and Two-step Mechanics

Not Applicable

• Conditions: Bimaxillary Protrusion; Orthodontic Space Closure; Malocclusion, Angle Class I
• Interventions: Procedure: En masse anterior teeth retraction; Procedure: Two-Step Retraction

• Registration Number: NCT03903575
• Lead Sponsor: Rio de Janeiro State University

Brief Summary

The aim of this study is to compare en masse (EM) and two-step anterior teeth retraction (TSR) evaluated by means of three-dimensional images superimposition. Thirty-two adult patients with bimaxillary protrusion planed for treatment with four first premolar extractions will be enrolled. All patients will be randomly allocated in a 1:1 ratio to either EM (n=16) group or the TSR (n=16) group. Cone bean computed tomography will be taken before and after anterior retraction. A blind observer will construct separate 3D models for maxillary and mandibular surfaces using the anterior cranial fossa to register models of before and after space closing. Quantitative assessment of posterior anchorage loss and amount of anterior teeth retraction are the main outcomes. The secondary outcomes are the inclination of the molars, canines and incisors.

Detailed Description

Not available

Study Timeline

• Status Verified: 2019-04
• Study Start: 2019-04-03
• Study First Submitted: 2019-04-03
• Study First Submitted QC: 2019-04-03
• Last Update Submitted: 2019-04-03
• Study First Posted: 2019-04-04
• Last Update Posted: 2019-04-05
• Primary Completion: 2020-04
• Study Completion: 2020-12

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 32

Inclusion Criteria

• Angle Class I malocclusion;
• Bimaxillary protrusion;
• Convex profile;
• All natural teeth present in the mouth;
• Absence of crowding or with negative discrepancy up to 4mm;
• Absence of vertical and transverse occlusal problems;
• Good oral health;
• Good general health.

Exclusion Criteria

• Lack of time to attend consultations;
• Patients with severe systemic and psychological illness;
• Patients with parafunction (bruxism), reflux or eating disorders;
• Presence of periodontal disease;

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
En Masse Retraction	En masse anterior teeth retraction	Group treated by retracting the six anterior teeth simultaneously.
Two-Step Retraction	Two-Step Retraction	Group treated by retracting the canines incisors in two different steps.

Primary Outcome Measures

Name	Time	Method
Anchorage loss	12 months	Quantitative assessment of posterior anchorage loss between the two groups as measured by tomographic superimposition at the end of space closure.
Anterior teeth retraction	12 months	Quantitative assessment of anterior teeth retraction between the two groups as measured by tomographic superimposition at the end of space closure.

Secondary Outcome Measures

Name	Time	Method
Molar inclination	12 months	Quantitative assessment of molars inclination between the two groups as measured by tomographic superimposition at the end of space closure.
Incisors inclination	12 months	Quantitative assessment of incisors inclination between the two groups as measured by tomographic superimposition at the end of space closure.
Canine inclination	12 months	Quantitative assessment of canines inclination between the two groups as measured by tomographic superimposition at the end of space closure.

Trial Locations

Locations (1)

Faculdade de Odontologia - UERJ; 🇧🇷 Rio de Janeiro, Brazil