Treating Growing Patients With Mandibular Prognathism and Maxillary Constriction

Radiographic Analysis of Skeletal and Dentoalveolar Changes Following the Treatment of Mandibular Prognathism and Maxillary Constriction in Growing Patients Using Two Different Treatment Protocols: A Randomized Controlled Trial

This randomized controlled trial intends to test the efficacy of two treatment protocols in the correction of Class III malocclusion with maxillary constriction. We have to options, either to modify the growth using inter-maxillary traction based on an upper fixed appliance that is used in the same time for rapid maxillary expansion or to inhibit mandibular growth by a removable mandibular retractor (RMR) supplied with an expansion screw.

Study Overview

• Status: Completed
• Conditions: Class III Malocclusion
• Intervention / Treatment: Device: RMR+SME; Device: BAIMT+RME

• Study Type: Interventional
• Enrollment (Actual): 26
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Syrian Arab Republic
  • Damascus, Syrian Arab Republic, DM20 HAJ72
    • Department of Orthodontics, Faculty of Dentistry, University of Damsacus
  • Damascus, Syrian Arab Republic, DJ223QX
    • Adib Al-Lahham Center, Damascus Health Directorate, Ministry of Health

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. growing male and female patients aged between 12 and 15 years
2. Angle's class III malocclusion
3. skeletal class III relationship judged clinically and confirmed radiographically (-4 < ANB < + 1)
4. An anterior crossbite involving two or more teeth or an edge-to-edge incisor relationship with or without an anterior shift of the lower jaw upon closure
5. normal inclination of the lower incisors or slightly proclined (i.e., the IMPA between 85° and 100°
6. maxillary constriction requiring expansion judged clinically and confirmed radiographically
7. permanent dentition
8. no previous orthodontic treatment

Exclusion Criteria:

1. skeletal class III malocclusion caused predominantly by maxillary deficiency (SNA<78° with a normal SNB angle)
2. severe skeletal class III presenting mainly due to mandibular protrusion (ANB < - 4° with no functional shift on closure)
3. contraindications for the use of the mini-screws, such as osteoporosis (addressed with cortisone and its derivatives) or those undergoing radiation treatment
4. a convergence between the mandibular canine root and the first premolar root ,which was assessed radiographically
5. facial asymmetry, characterized by a mandibular midline deviation exceeding 2 mm from the facial midline
6. MM angle >35° or SN-MP angle > 40°
7. The existence of cleft lip or craniofacial syndromes and/or palate abnormalities and
8. The existence of supernumerary teeth or missing ones except for the third molars.

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: RMR with SME; The removable mandibular retractor (RMR) will inhibit mandibular growth. This appliance will be supplemented with a medline screw that is used for slow maxillary expansion (SME).	Device: RMR+SME; Patients will be asked to wear this removable appliance for 16 hours daily. The expansion screw is activated twice a week.
Active Comparator: BAIMT with RME; Bone-anchored intermaxillary traction (BAIMT) will be used for Class III correction. This upper part of the appliance is used for rapid maxillary expansion (RME).	Device: BAIMT+RME; The elastics are worn 18 hours per day to achieve the sagittal correction. The RME appliance on the upper jaw is activated twice daily until the required expansion is achieved.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in the SNB angle	his angle represents the position of the lower jaw in the cephalometric analysis in the anteroposterior direction. Lateral cephalograms will be taken, and this angle will be measured in degrees.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the SN-GoMe angle	This angle represents the position of the lower jaw in the cephalometric analysis in the vertical direction. Lateral cephalograms will be taken, and this angle will be measured in degrees.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the MM angle	This angle represents the amount of vertical divergence between the upper and lower jaws in the cephalometric analysis. Lateral cephalograms will be taken, and this angle will be measured in degrees.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the Co.Go.Me angle	This angle is created by the intersection between the ramus plane (Co.Go) and the mandibular plane (Go.Me). This is called the gonial angle.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the mandibular length	This distance is measured between the mandibular condyle (Co) and the genial point (Gn).	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the ramus height	This distance is measured between the mandibular condyle (Co) and mandibular gonial angle (Go).	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the A-H variable	This variable is the horizontal distance between A point (the maxillary bone point) and the perpendicular plane to the S-N plane through Point S (Sella).	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the B-H variable	This variable is the horizontal distance between B point (the mandibular bone point) and the perpendicular plane to the S-N plane through Point S (Sella).	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the GoMe-L1 angle	This angle represents the relationship of the lower anterior teeth with the mandibular plane in the cephalometric analysis in the anteroposterior direction. Lateral cephalograms will be taken, and this angle will be measured in degrees.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the Gla-Sn-Pog angle	It is the angle between the soft tissue forehead point (Gla) and the subnasal point (Sn) and the most anterior point on the soft tissue chin (Pog).	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the naso-labial angle	It is the angle between the upper lip and nasal columella plane.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the labio-mental angle	It is the angle between the lower lip and the chin. It is also called the labio-mental fold angle..	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the Ag to MZF-j variable	Maxillomandibular width right: measured from the Jugal process to the frontofacial plane. This measurement is measured on the frontal cephalogram.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the J-J distance	It is the maxillary width measured on the frontal cephalogram.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the molar width at the level of apices (M-MRA)	This is measured between the apices of the palatal roots of the maxillary first molars (R.RA-L.RA) on the frontal cephalogram.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the inferred molar tipping (M-tip)	The difference between R.RA-L.RA and R.CT-L.CT variables mentioned above and the difference is given in mm.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the SNA angle	This angle represents the position of the upper jaw in the cephalometric analysis in the anteroposterior direction. Lateral cephalograms will be taken, and this angle will be measured in degrees.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the ANB angle	This angle represents the relationship between the upper and lower jaws in the cephalometric analysis in the anteroposterior direction. Lateral cephalograms will be taken, and this angle will be measured in degrees.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the SN-SPP angle	This angle represents the position of the upper jaw (represented by the spinal plane "SPP") in the vertical direction of the cephalometric analysis. Lateral cephalograms will be taken, and this angle will be measured in degrees.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the Witz appraisal	Witz appraisal is measured by the anteroposterior distance between the projections of Points A and B onto the functional occlusal plane, measured in mm. It gives an idea about the sagittal relationship between the upper and lower jaws.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the lower facial height	This distance is measured between the anterior nasal spine (ANS) and the lower point on the mandibular symphysis (Me).	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the SN-U1	This angle represents the relationship of the upper anterior teeth with SN in the cephalometric analysis in the anteroposterior direction. Lateral cephalograms will be taken, and this angle is going to be measured in degrees.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the SPP-U1 angle	This angle represents the relationship of the upper anterior teeth with the SPP plane in the cephalometric analysis in the anteroposterior direction. Lateral cephalograms will be taken, and this angle will be measured in degrees.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in ls-E Line distance	It is the distance between Ricketts's esthetic line and the upper lip point.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in li-E Line distance	It is the distance between the lower lip point and esthetic line of Ricketts.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months
Change in the molar width at the level of cusps (M-MCT)	This is measured between the mesio-palatal cusps tips of the maxillary first molars (R.CT-L.CT) on the frontal cephalogram.	At two assessment times: (1) one day before the beginning of the treatment, and (2) at the end of the retention phase which is expected to occur within 12 months

Collaborators and Investigators

• Sponsor: Damascus University
• Collaborators: Universiti Sains Malaysia
• Investigators: Study Director: Mohammad Younis Hajeer, DDS MSc PhD, Department of Orthodontics, Faculty of Dentistry, Damascus University, Damascus, Syria

Publications and helpful links

General Publications

• Saleh M, Hajeer MY, Al-Jundi A. Assessment of pain and discomfort during early orthodontic treatment of skeletal Class III malocclusion using the Removable Mandibular Retractor Appliance. Eur J Paediatr Dent. 2013 Jun;14(2):119-24.
• Saleh M, Hajeer MY, Al-Jundi A. Short-term soft- and hard-tissue changes following Class III treatment using a removable mandibular retractor: a randomized controlled trial. Orthod Craniofac Res. 2013 May;16(2):75-86. doi: 10.1111/ocr.12007. Epub 2012 Nov 8.
• Majanni AM, Hajeer MY. The Removable Mandibular Retractor vs the Bone-anchored Intermaxillary Traction in the Correction of skeletal class III Malocclusion in children: A Randomized Controlled Trial. J Contemp Dent Pract. 2016 May 1;17(5):361-71. doi: 10.5005/jp-journals-10024-1856.
• Rabah N, Al-Ibrahim HM, Hajeer MY, Ajaj MA. Evaluation of rapid versus slow maxillary expansion in early adolescent patients with skeletal maxillary constriction using cone-beam computed tomography: A short-term follow-up randomized controlled trial. Dent Med Probl. 2022 Oct-Dec;59(4):583-591. doi: 10.17219/dmp/133513.
• Rabah N, Al-Ibrahim HM, Hajeer MY, Ajaj MA, Mahmoud G. Assessment of Patient-Centered Outcomes When Treating Maxillary Constriction Using a Slow Removable Versus a Rapid Fixed Expansion Appliance in the Adolescence Period: A Randomized Controlled Trial. Cureus. 2022 Mar 3;14(3):e22793. doi: 10.7759/cureus.22793. eCollection 2022 Mar.

Study record dates

Study Major Dates

• Study Start (Actual): September 15, 2021
• Primary Completion (Actual): January 15, 2023
• Study Completion (Actual): September 15, 2023

Study Registration Dates

• First Submitted: December 31, 2024
• First Submitted That Met QC Criteria: December 31, 2024
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: March 9, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Musculoskeletal Diseases; Stomatognathic Diseases; Jaw Diseases; Tooth Diseases; Jaw Abnormalities; Maxillofacial Abnormalities; Craniofacial Abnormalities; Musculoskeletal Abnormalities; Mandibular Diseases; Stomatognathic System Abnormalities; Congenital Abnormalities; Malocclusion; Prognathism; Malocclusion, Angle Class III
• Other Study ID Numbers: UDDS-Ortho-1-2025

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