Comparison of Maxillary Protraction Using Tooth-borne Facemask Versus Skeletal Anchorage Chin-plate in Class III Growing Patients

Universidad Complutense de Madrid

Status: Not yet enrolling

Conditions: Skeletal Class III Malocclusion

Treatments: Device: Hybrid Skeletal Anchorage Expander with Chin-Plate (SA); Device: Tooth-Borne Expander with Facemask (FM)

Study type: Interventional

Funder types: Other

Identifiers

NCT07383259

Mentoplac_FaceMask

Details and patient eligibility

About

This retrospective non-randomized controlled clinical trial aimed to compare the skeletal and dentoalveolar effects of two orthopedic treatment protocols for skeletal Class III malocclusion in growing patients: a conventional tooth-borne rapid maxillary expansion combined with facemask therapy, and a hybrid skeletal anchorage expander combined with chin-plate traction. Lateral cephalometric changes before and after maxillary protraction were analyzed to assess sagittal skeletal correction and dentoalveolar effects.

Full description

Skeletal Class III malocclusion is frequently associated with maxillary growth deficiency and presents significant functional and esthetic challenges. Conventional treatment using rapid maxillary expansion combined with facemask therapy is effective but limited by patient compliance and undesirable dentoalveolar effects. The introduction of skeletal anchorage devices allows the application of orthopedic forces with reduced dental compensation and extended effectiveness beyond early growth stages.

This study retrospectively evaluated growing patients (CVS1-CVS3) treated with either a tooth-borne expander and facemask or a hybrid skeletal anchorage expander combined with chin-plate traction. Cephalometric variables were measured before treatment (T0) and after completion of maxillary protraction (T1) to compare skeletal and dentoalveolar changes between protocols.

Enrollment: 36 estimated patients

Sex: All

Ages: Under 18 years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Inclusion Criteria

• Growing patients (CVS1-CVS3)
• Patent midpalatal suture (stages A-C)
• Skeletal Class III malocclusion (ANB < 0°, Wits < -2 mm)
• Presence of anterior crossbite or edge-to-edge incisal relationship Exclusion Criteria
• Severe craniofacial asymmetry
• Evidence of active condylar growth
• Previous orthodontic treatment
• Craniofacial malformations or syndromes
• Systemic diseases or medications affecting growth or bone metabolism

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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36 participants in 2 patient groups

Tooth-Borne Expander with Facemask (FM)

Active Comparator group

Description:

Bonded acrylic splint-type Hyrax expander with hooks in the maxillary canine region. Expansion activated once daily (0.25 mm). Facemask therapy initiated two weeks after expansion onset with 400 g per side of elastic traction, directed approximately 30° downward relative to the occlusal plane, worn 14-16 hours per day.

Treatment:

Device: Tooth-Borne Expander with Facemask (FM)

Hybrid Skeletal Anchorage Expander with Chin-Plate (SA)

Experimental group

Description:

Modified Hybrid Hyrax expander supported by first molars and anchored with miniscrews placed bilaterally in a paramedian position. Expansion activated once daily (0.25 mm). Mandibular chin-plates (bollard-type or single chin-plate depending on eruption stage) were surgically inserted, and Class III elastics delivering 400 g per side were applied following a progressive loading protocol.

Treatment:

Device: Hybrid Skeletal Anchorage Expander with Chin-Plate (SA)