Root Shortening With Three Methods of Upper Front Teeth Retraction

Summary

External apical root resorption is a possible side effect of fixed orthodontic treatment, particularly in the upper front teeth. This randomized clinical trial was conducted to compare the amount and timing of root resorption associated with three different methods of retracting the upper anterior teeth using miniscrew anchorage. Sixty adult patients with Class II Division 1 malocclusion who required extraction of the upper first premolars were randomly allocated to one of three groups: a bidimensional bracket group, a hybrid dual-section archwire group, or a conventional sliding mechanics group. In all groups, the six upper anterior teeth were retracted together with the support of orthodontic miniscrews. Panoramic radiographs were obtained before treatment, after completion of leveling and alignment, and after completion of en-masse retraction. Root and crown lengths were measured on these radiographs to estimate external apical root resorption during the leveling and alignment phase, during the retraction phase, and over the complete observation period. The study also compared the pattern of resorption among the upper canines, lateral incisors, and central incisors.

Conditions

• CLASS II DIVISION 1 MALOCCLUSION

Interventions

PROCEDURE

Bidimensional Bracket System

Fixed orthodontic treatment will be performed using 0.018-inch slot brackets from canine to canine and 0.022-inch slot brackets on the posterior teeth. After leveling and alignment, en-masse retraction will be performed on a 0.018 × 0.025-inch stainless-steel archwire using bilateral orthodontic miniscrews and nickel-titanium closed-coil springs delivering 250 g of force per side.

PROCEDURE

Hybrid Dual-Section Archwire

Fixed orthodontic treatment will be performed using 0.022-inch slot brackets. En-masse retraction will be carried out using a customized stainless-steel archwire consisting of a 0.019 × 0.025-inch anterior section and 0.016 × 0.022-inch posterior sections, with the transitions located distal to the maxillary canines. Bilateral orthodontic miniscrews and nickel-titanium closed-coil springs delivering 250 g per side will be used.

PROCEDURE

Conventional Sliding Mechanics

Fixed orthodontic treatment will be performed using 0.022-inch slot brackets. En-masse retraction will be carried out on a continuous 0.019 × 0.025-inch stainless-steel archwire using bilateral orthodontic miniscrews and nickel-titanium closed-coil springs delivering 250 g of force per side.

Sponsors & Collaborators

• Damascus University

  lead OTHER

Principal Investigators

• Mohammad Younis Hajeer · Department of Orthodontics, Faculty of Dentistry, University of Damascus

• Abdulmalek M. H. Almasri · Department of Orthodontics, Faculty of Dentistry, University of Damascus

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

30 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2025-07-02

Primary Completion

2026-06-23

Completion

2026-06-28

Countries

• Syria

Study Locations