Effect of Bone-anchored Protraction on Maxillary Growth in the Young Child

Class III malocclusions may originate in a retrognathic maxilla, a prognathic mandible or both. Young patients with class III malocclusion and maxillary hypoplasia are conventionally treated with a protraction facemask in order to stimulate forward growth of the upper jaw. This treatment option is often inducing unwanted side effects including mesial migration of the teeth in the upper jaw and clockwise rotation of the mandible. Because skeletal effects are often difficult to achieve with this approach, more pronounced class III malocclusions cannot be addressed by face mask therapy. These children cannot be treated during childhood and end up in major orthognathic surgery at full-grown age. To be able to treat also the more pronounced class III malocclusion and to minimize dentoalveolar compensations new treatment methods were developed which uses skeletal anchorage.

Study Overview

• Status: Unknown
• Conditions: Maxillary Hypoplasia; Malocclusion, Angle Class III
• Intervention / Treatment: Device: orthodontic bone anchor; Device: Face mask

Detailed Description

Rationale:

Class III malocclusions may originate in a retrognathic maxilla, a prognathic mandible or both. Young patients with class III malocclusion and maxillary hypoplasia are conventionally treated with a protraction facemask or reverse twin block appliance in order to stimulate forward growth of the upper jaw. This treatment option is often inducing unwanted side effects including mesial migration of the teeth in the upper jaw and clockwise rotation of the mandible. Because skeletal effects are often difficult to achieve with this approach, more pronounced class III malocclusions cannot be addressed by face mask therapy. These children cannot be treated during childhood and end up in major orthognathic surgery at full-grown age.

To be able to treat also the more pronounced class III malocclusion and to minimize dentoalveolar compensations new treatment methods were developed which uses skeletal anchorage. In maxillary deficiency cases it's common to have the deficiency anteroposteriorly as well as transversely. Opening of the midpalatal suture by rapid expansion can correct the transverse hypoplasia and may produce more anterior movement of the maxilla. The proposed technique enables to start skeletal anchorage treatment at an earlier age, which also has the potential of more growth modification during treatment.

Objective:

To compare a new technique of skeletal traction with incorporation of maxillary expansion to conventional treatment protocols.

Study design:

This is a RCT

Study population:

Healthy human volunteers (7- 14 yrs old) with class III malocclusion due to maxillary deficiency.

Intervention:

The intervention consists of the application of a mentoplate (anchored with screws to the bone) in the lower jaw and two screws in the upper jaw (palate). Expansion in the upper jaw is achieved by a classic Hyrax appliance, connected to these screws. Anterior movement of the maxilla is subsequently accomplished by intermaxillary elastic traction to the mentoplate.

Control group (conventional treatment):

Anterior movement of the maxilla accomplished by elastic traction to a face mask

Main study parameters/endpoints:

The main study parameter is the difference in the amount of forward growth of the upper jaw and mid-face (measured with a cone beam CT) compared to the growth that is observed with conventional treatment.

A cone beam CT will be made before the start of traction therapy (baseline) and after 1 year of therapy to evaluate the amount of expansion and forward growth of the maxilla.

One last cone beam CT will be produced at the end of growth, 5 years after start of the orthodontic traction, to evaluate the long-term stability of the obtained advancement.

Other end-points will be patients' satisfaction and complication-rate.

• Study Type: Interventional
• Enrollment (Anticipated): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Belgium
  • Genk, Belgium, 3600
    • Ziekenhuis Oost Limburg

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 3 years to 10 years (Child)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

healthy subjects 7 - 14 years old Class III occlusion maxillary hypoplasia good oral hygiene no craniofacial syndrome

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: orthodontic bone anchor; new bone anchor device, which creates anterior traction on the upper jaw. Placed on the chin-region intra-orally.	Device: orthodontic bone anchor; to apply force on the upper jaw (24 / 7) via intra-oral elastics on the bone-anchor; Other Names: mentoplate, PSM medical solutions, Tuttlingen, Germany
Active Comparator: face mask protraction; control group, conventional treatment method. Face mask creates anterior traction on the upper jaw	Device: Face mask; to apply for on the upper jaw (12 - 14 hrs / day) via extra-oral elastics to the face mask; Other Names: face mask of dealer

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
effect of bone-anchored protraction on maxillary growth in the young child, 1 year with 3D analysis	assessment of anterior growth of the upper jaw, 1 year after start of treatment	1 year
effect of bone-anchored protraction on maxillary growth in the young child, 5 years, with 3D analysis	assessment of anterior growth of the upper jaw, 5 years after start of treatment	5 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
complications registration	registration of complications due to the use of the new orthodontic bone anchor (mentoplate)	1 year
patient satisfaction	registration of the patient satisfaction, easy to use	1 year

Collaborators and Investigators

• Sponsor: Ziekenhuis Oost-Limburg

Study record dates

Study Major Dates

• Study Start: April 1, 2016
• Primary Completion (Anticipated): December 1, 2017
• Study Completion (Anticipated): December 1, 2021

Study Registration Dates

• First Submitted: March 7, 2016
• First Submitted That Met QC Criteria: March 11, 2016
• First Posted (Estimate): March 17, 2016

Study Record Updates

• Last Update Posted (Estimate): March 18, 2016
• Last Update Submitted That Met QC Criteria: March 16, 2016
• Last Verified: March 1, 2016

More Information

Terms related to this study

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