Dental Changes Following the Traction of Impacted Maxillary Canines

Evaluation of the Dental Changes Associated With the Traction of Palatally Impacted Canines Using the Conventional Versus the Corticotomy-assisted Method: A Randomized Controlled Trial

The impaction of maxillary canines is a challenge for orthodontists. Recently, new methods have been proposed to accelerate canine withdrawal. The associated dental changes between the conventional and accelerated methods of canine traction have not yet been assessed.

Study Overview

• Status: Completed
• Conditions: Impaction of Tooth
• Intervention / Treatment: Procedure: Corticotomy; Procedure: Conventional traction

Detailed Description

Impacted canines are defined as those that have not erupted within 6 six months after completing the formation of their roots or that were not present within the dental arch during their eruption phase. Upper Impacted canines are present in 2% of the general population and occur in females at a rate of 1.17%, which is almost twice the incidence in males. The incidence of palatal impaction ranges from 60% to 80% and is present bilaterally with a rate of 75-95%. The upper canines usually erupt at an average age of 10.5 years in females and 11.5 years in males, with an individual difference of 3-4 years. Eruption failure of the upper canines occurs because of hard or soft tissue obstructions or an abnormal eruption pathway.

The most important causes of palatally impaction of upper canines are dental arch length deficiency, over-retained primary teeth, and trauma during the canine formation stage. One local mechanical cause is a decrease in the width of the upper dental arch. McConnell et al. reported that patients with upper impacted canines had a reduction in dental arch width, especially in the anterior region. On the other hand, unilateral or bilateral upper canine impaction can affect upper dental arch width and alter smile symmetry.

The impaction of the upper canine is also considered as one of the causes that lead to a lack of transverse development of the maxillary dental arch, especially the inter-premolar width. This is supported by the functional matrix theory, which considers that the presence of the organ stimulates bone growth. Thus, the natural eruption of the canine stimulates the normal transverse growth of the dental arch.

Many treatment strategies were used to treat impacted canine cases, but orthodontic traction after surgical exposure was the most commonly recommended method in the literature, given the great aesthetic and functional value of the upper canines. Two main surgical methods are used for this purpose: the open and closed surgical approaches.

Several mechanical means have been used to obtain the traction force. However, choosing the appropriate mechanical method that produces the least undesirable effects on adjacent teeth was a challenge for the clinical practitioner.

Many factors could result in unwanted changes in the spatial position of the adjacent teeth, such as the use of an open coil spring, direct reliance on these teeth to tract the impacted canine, the type of baseline orthodontic archwire used, and the type of orthodontic anchorage means. These side effects on adjacent teeth can be minimized by using techniques such as the segmented archwire technique and temporary anchorage devices (TADs).

• Study Type: Interventional
• Enrollment (Actual): 44
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Syria
  • Rif-dimashq Governorate
    • Damascus, Rif-dimashq Governorate, Syria, DM20AM19
      • Orthodontics Department, Faculty of Dentistry

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. patients' ages ranged from 18 to 28 years old
2. unilaterally palatally or mid-alveolar upper impacted canine
3. patients who have never received orthodontic treatment previously
4. mild crowding of the maxillary arch (less than 4 mm) and class I first molars relation

Exclusion Criteria:

1. bilateral or buccal canine impaction
2. patients who have a contraindication to perform oral surgery under local anesthesia (social, psychological, mor edical)
3. more than 45-degree angle between the longitudinal axis of the impacted canines and the facial midline
4. bad oral health

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Accelerated canine traction group; Perforations of the bone surrounding the impacted canine will be conducted at the time of canine exposure. Two months later, another flapless corticotomy procedure will be performed during the withdrawal of the impacted canine.	Procedure: Corticotomy; During the surgical exposure phase in the acceleration group, the cortical bone will be perforated around the exposed canine crown (6-8 holes) wherever possible-this procedure aims to accelerate the withdrawal movement of the impacted canine. A 1 mm round bur will be used to create circular holes (1 mm in diameter, 1-2 mm in depth, and spaced about 1.5 mm apart). After two months of the surgical exposure, the second acceleration procedure will be performed. Two or three vertical incisions (8 mm height) will be made using a surgical scalpel at the buccal side of the impaction area. The cortical cuts (2-3 mm in depth, 1 mm in width, and spaced about 2 mm apart) will be performed using a flapless piezosurgery technique along the vertical lines.; Other Names: flapless corticotomy; piezosurgery; piezocision
Active Comparator: Conventional canine traction; The canines will be withdrawn to the dental arch using the conventionnal method without subjecitng the patient to any additional surgical intervention.	Procedure: Conventional traction; The canines will be withdrawn using conventional methods without any surgical acceleration.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in the upper dental midline deviation	The deviation of the upper dental midline will be measured in millimeters as the distance from the maxillary central incisors contact point to the maxillary model midline. This will be performed on the plaster models.	T1: before the commencement of canine traction (expected to occur within 3-5 months following the beginning of fixed orthodontic treatment). T2: at the end of the canine traction stage (expected to occur with 5-8 months after T1)
Change in the rotation of the lateral incisor.	The rotation will be measured in degrees as the angle between the maxillary model midline and the line connecting the mesial-distal marginal points of the adjacent lateral incisor.	T1: before the commencement of canine traction (expected to occur within 3-5 months following the beginning of fixed orthodontic treatment). T2: at the end of the canine traction stage (expected to occur with 5-8 months after T1)
Change in the rotation of the first premolar	The rotation will be measured in degrees as the angle between the maxillary model midline and the line connecting the mesial-distal marginal points of the adjacent first premolar.	T1: before the commencement of canine traction (expected to occur within 3-5 months following the beginning of fixed orthodontic treatment). T2: at the end of the canine traction stage (expected to occur with 5-8 months after T1)
Change in the inter-premolar width	Inter-premolar width will be measured in millimeters as the distance from the deepest point in the central groove of the adjacent first premolar and its counterpart on the contralateral side	T1: before the commencement of canine traction (expected to occur within 3-5 months following the beginning of fixed orthodontic treatment). T2: at the end of the canine traction stage (expected to occur with 5-8 months after T1)

Collaborators and Investigators

• Sponsor: Damascus University
• Investigators: Principal Investigator: Mahran Raheel Mousa, DDS, MSc, PhD, Department of Orthodontics, Faculty of Dentistry, Al-Hawash Private University, Homs, Syria; Study Director: Mohammad Younis Hajeer, DDS, MSc, PhD, Department of Orthodontics, Faculty of Dentistry, Damascus University; Study Director: Omar Ahmad Heshmeh, DDS, MSc, PhD, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Damascus University

Publications and helpful links

General Publications

• Fischer TJ. Orthodontic treatment acceleration with corticotomy-assisted exposure of palatally impacted canines. Angle Orthod. 2007 May;77(3):417-20. doi: 10.2319/0003-3219(2007)077[0417:OTAWCE]2.0.CO;2.
• Alyafrusee ES, Zheng B, Almashraqi AA, Almaqrami BS, Yang X, Xu H, Alhammadi MS, Liu Y. Three-dimensional dentoalveolar characteristics of a labially impacted dilacerated maxillary central incisor using cone-beam computed tomography. Sci Rep. 2025 Jul 9;15(1):24669. doi: 10.1038/s41598-025-10043-9.
• Hocevar M, Ovsenik M, Golez A. Position of Maxillary Lateral Incisor and First Premolar in Impaction of Maxillary Canines: A Controlled Clinical CBCT and 3D Study Model Analysis. Dent J (Basel). 2025 Oct 27;13(11):497. doi: 10.3390/dj13110497.
• Mousa MR, Hajeer MY, Burhan AS, Heshmeh O. Adult periodontal comparison after treatment of palatally impacted canines aligned by conventional or accelerated minimally-invasive corticotomy-assisted orthodontic traction: A randomized controlled trial. Int Orthod. 2023 Sep;21(3):100785. doi: 10.1016/j.ortho.2023.100785. Epub 2023 Jun 15.
• Mousa MR, Hajeer MY, Burhan AS, Heshmeh O, Alam MK. The effectiveness of minimally-invasive corticotomy-assisted orthodontic treatment of palatally impacted canines compared to the traditional traction method in terms of treatment duration, velocity of traction movement and the associated dentoalveolar changes: A randomized controlled trial. F1000Res. 2023 Jun 19;12:699. doi: 10.12688/f1000research.135338.1. eCollection 2023.

Study record dates

Study Major Dates

• Study Start (Actual): March 2, 2023
• Primary Completion (Actual): October 15, 2024
• Study Completion (Actual): January 19, 2025

Study Registration Dates

• First Submitted: December 7, 2025
• First Submitted That Met QC Criteria: December 7, 2025
• First Posted (Estimated): December 19, 2025

Study Record Updates

• Last Update Posted (Actual): December 29, 2025
• Last Update Submitted That Met QC Criteria: December 20, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Stomatognathic Diseases; Tooth Diseases; Tooth, Impacted; Surgical Procedures, Operative; Ultrasonic Surgical Procedures; Piezosurgery
• Other Study ID Numbers: UDDS-2025-Ortho-11

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No