Class III Skeletal Malocclusion
Conditions
Keywords
Class III malocclusion, RME/FM, Mini maxillary protractor, SEC III, 3D stereophotogrammetry, Soft tissue, Cephalometry
Brief summary
This clinical trial compares three different treatment methods used to correct jaw problems in children with Class III malocclusion (a condition where the lower jaw is positioned forward relative to the upper jaw). The treatments include: Rapid maxillary expansion with face mask (RME/FM), Mini maxillary protractor (MMP), Modified splints with elastics and chin cup (SEC III). The study aims to understand how each treatment affects the bones and soft tissues of the face, such as how much the upper jaw moves forward or the lower jaw moves backward, as well as changes in teeth alignment and facial appearance. Results showed that different treatments work best for different aspects: some are better for moving the upper jaw forward, while others are better for repositioning the lower jaw. This information helps doctors choose the most suitable treatment plan for each patient.
Detailed description
This prospective randomized controlled clinical trial evaluates and compares the skeletal and three-dimensional soft tissue effects of three orthopedic treatment protocols in growing patients with Class III skeletal malocclusion. A total of 43 patients were randomly assigned to one of three treatment groups: rapid maxillary expansion with face mask (RME/FM), mini maxillary protractor (MMP), and modified splints with elastics and chin cup (SEC III). Additionally, a control group was formed from archival records of untreated patients with similar malocclusion characteristics. Patients underwent comprehensive evaluation before and after treatment, including lateral cephalometric radiographs and 3D stereophotogrammetry to capture skeletal and soft tissue changes. Key parameters measured were maxillary and mandibular skeletal movements, dental inclination changes, overjet and overbite adjustments, as well as facial soft tissue displacement and angular measurements. The study's design ensured rigorous randomization and controlled conditions to objectively assess the efficacy of each treatment protocol. The outcomes provide insight into how each method influences skeletal advancement or retrusion, dental positioning, and facial profile alterations, offering guidance for personalized treatment planning in orthodontic practice.
Interventions
DEVICERapid Maxillary Expansion with Face Mask (RME/FM)
A tooth- and tissue-borne rapid maxillary expansion appliance with an expansion screw was used to achieve transverse maxillary expansion, followed by Petit-type face mask therapy. Expansion protocol: two quarter-turns per day for 10-14 days, then one quarter-turn per day until cusp-to-cusp relationship was achieved. Face mask elastics applied 16 hours/day at 350-500 g per side, with a 30° downward and forward vector relative to the occlusal plane.
DEVICEMini Maxillary Protractor (MMP)
An intraoral mini maxillary protraction appliance was used to advance the maxilla. Force was applied through intraoral elastics connected to intraoral anchorage units. The protocol was designed to deliver orthopedic forward traction of the maxilla without an external face mask.
DEVICEModified Splint with Elastics and Chin Cup (Modified SEC III)
A modified splint appliance combined with intraoral elastics and an orthopedic chin cup was used to achieve skeletal mandibular retrusion and Class III correction. The appliance applied orthopedic forces through combined vertical and horizontal components, promoting backward positioning of the mandible while maintaining transverse maxillary relationships.
Sponsors
TC Erciyes University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
This study uses a parallel assignment design, where participants with Class III skeletal malocclusion are randomly assigned to one of three treatment groups: rapid maxillary expansion with face mask (RME/FM), mini maxillary protractor (MMP), or modified splints with elastics and chin cup (SEC III). Additionally, a control group consisting of untreated patients with similar malocclusion characteristics from archival records is included for comparison. Each treatment group receives its specific intervention simultaneously, and outcomes are compared among all groups to evaluate the efficacy of each protocol.
Eligibility
Sex/Gender
ALL
Age
9 Months to 12 Months
Healthy volunteers
No
Inclusion criteria
* Individuals who have not completed their growth spurt (9-12 years old) * Overjet ≤ 0 mm (patients with negative overjet must be De Nevreze positive) * ANB ≤ 0°, Witts \< 1 * Good oral hygiene and healthy periodontal tissues * SN-GoGn angle between 26° and 38° * No congenital or acquired tooth loss (excluding third molars) * Body mass index (BMI) between 18-26 kg/m² * No systemic, local, or endocrinological diseases
Exclusion criteria
* Presence of any syndrome or developmental deformity * Previous orthodontic treatment * Allergy to any metal or acrylic * Presence of any systemic disease affecting treatment * SN-GoGn angle \> 38° * Presence of temporomandibular joint disorders
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Three-dimensional changes in soft tissues | baseline to post-treatment (≈ 9 months) | 3D stereophotogrammetry used to assess overall soft tissue profile changes, including facial convexity and lip-chin parameters. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Two dimensional changes in skeletal parameters of the maxilla and mandible | Baseline (pre-treatment) to post-treatment (≈ 9 months) | Lateral cephalometric radiographs used to evaluate overall skeletal changes in maxillary and mandibular positions, as well as dental parameters including overjet and overbite. |
Countries
Turkey (Türkiye)
Outcome results
None listed