NCT03903575

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

3D Comparison of Anterior Teeth Retraction and Anchorage Control Between En-masse and Two-step Mechanics: A Randomized Prospective Clinical Trial

• Status: Unknown
• Phase: N/A
• Study type: Interventional
• Enrollment: 32 (estimated)
• Sponsor: Rio de Janeiro State University · Academic / Other
• Sex: All
• Age: 18 Years – 40 Years
• Healthy volunteers: Accepted

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.

Conditions

• Malocclusion, Angle Class I
• Bimaxillary Protrusion
• Orthodontic Space Closure

Interventions

Type	Name	Description
PROCEDURE	En masse anterior teeth retraction	After extraction of the four premolars the posterior teeth will be tied-together and the six anterior teeth will be retracted by sliding mechanics.
PROCEDURE	Two-Step Retraction	After extraction of the four premolars the posterior teeth will be tied-together and the canines will be retracted by sliding mechanics. After the distalization of the canines they will be tied to the posterior teeth and the incisors will be retracted by sliding mechanics.

Timeline

• Start date: 2019-04-03
• Primary completion: 2020-04-01
• Completion: 2020-12-01
• First posted: 2019-04-04
• Last updated: 2019-04-05

Locations

1 site across 1 country: Brazil