NCT07458139

Comparison of Root Resorption in Modified Corticotomy-Assisted and Conventional Canine Retraction

Comparison of External Apical Root Resorption in Modified Corticotomy-Assisted and Conventionally Retracted Maxillary Canines Using Frictionless T-Loop Mechanics: A Randomized Controlled Clinical Trial

• Status: Not Yet Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 60 (estimated)
• Sponsor: Islamabad Medical and Dental College · Academic / Other
• Sex: All
• Age: 12 Years – 30 Years
• Healthy volunteers: Accepted

Summary

This randomized controlled clinical trial will compare external apical root resorption in patients undergoing maxillary canine retraction using modified corticotomy-assisted frictionless T-loop mechanics versus conventional frictionless T-loop mechanics. Sixty orthodontic patients requiring extraction of maxillary first premolars will be randomly assigned to two groups. Changes in canine root length will be measured on panoramic radiographs taken before and after retraction to determine the extent of external apical root resorption. The study will evaluate whether modified corticotomy-assisted retraction results in different root resorption outcomes compared to conventional retraction.

Detailed description

External apical root resorption is a known complication of orthodontic treatment and may be influenced by the magnitude and duration of orthodontic force. Methods that accelerate tooth movement may reduce overall treatment time and potentially influence the extent of root resorption. Corticotomy-assisted orthodontics is based on the regional acceleratory phenomenon, which enhances bone remodeling and facilitates tooth movement. Modified corticotomy techniques involve limited surgical injury to the cortical bone to stimulate accelerated movement while minimizing postoperative morbidity. Frictionless mechanics using T-loops allow controlled canine retraction with reduced frictional resistance between the bracket and archwire. This single-center randomized controlled clinical trial will enroll 60 patients aged 12 to 30 years who require bilateral extraction of maxillary first premolars as part of orthodontic treatment. Participants will be randomly allocated in a 1:1 ratio to: Group A: Modified corticotomy-assisted canine retraction with frictionless T-loop mechanics Group B: Conventional frictionless T-loop canine retraction All participants will be treated using 0.022 × 0.028-inch preadjusted edgewise appliances. Standardized T-loop activation delivering controlled force will be performed at three-week intervals until canine retraction is completed. External apical root resorption will be assessed by measuring linear changes in root length from the canine cusp tip to the root apex on calibrated pre- and post-retraction panoramic radiographs using digital measurement software. The primary outcome measure will be the mean change in root length between baseline and post-retraction assessments. Statistical analysis will compare the magnitude of root resorption between the two groups.

Conditions

• External Apical Root Resorption in Maxillary Canines During Orthodontic Retraction

Interventions

Type	Name	Description
PROCEDURE	Modified Corticotomy assisted frictionless canine retraction	A surgical procedure in which a buccal flap is elevated and two vertical corticotomy cuts are made in the maxillary cortical bone adjacent to the extraction site to accelerate orthodontic tooth movement.
PROCEDURE	Conventional Frictionless Canine retraction	Orthodontic space closure using 17×25 TMA T-loops activated to deliver approximately 200 g of force for frictionless canine retraction into maxillary first premolar extraction spaces.

Timeline

• Start date: 2026-03-01
• Primary completion: 2026-07-01
• Completion: 2026-07-01
• First posted: 2026-03-09
• Last updated: 2026-03-09

Locations

1 site across 1 country: Pakistan