Mandibular Retrognathia, Skeletal Class II Malocclusion
Conditions
Keywords
Twin Block Appliance, Mandibular Advancement, Functional Appliance, Cone Beam Computed Tomography, Temporomandibular Joint, Growing Patients, Class II Malocclusion
Brief summary
This study compares two types of dental appliances a fixed Twin Block appliance and a conventional (removable) Twin Block appliance used to treat a bite problem called skeletal Class II malocclusion in growing children and teenagers. In this condition, the lower jaw is positioned further back than the upper jaw. Both appliance types work by guiding the lower jaw forward during growth. The study uses 3D imaging (cone beam computed tomography, or CBCT) before and after treatment to measure how each appliance affects the bones of the jaw, the teeth, the soft tissue profile of the face, and the jaw joint (temporomandibular joint). The goal is to determine whether the fixed or the conventional version of the appliance produces better treatment outcomes.
Detailed description
This comparative clinical study evaluates the skeletal, dentoalveolar, soft-tissue, and condylar/temporomandibular joint (TMJ) effects of fixed versus conventional Twin Block appliances in growing patients diagnosed with skeletal Class II malocclusion due to mandibular retrognathia. Participants were allocated to receive treatment with either a fixed or a conventional (removable) Twin Block appliance. Pre-treatment and post-treatment cone beam computed tomography (CBCT) scans were obtained to assess sagittal jaw relationships, mandibular advancement, dentoalveolar changes (including overjet and overbite correction), soft-tissue profile changes, and condylar position/remodeling within the glenoid fossa, including TMJ disc space measurements. Outcomes between the two appliance groups were compared to evaluate differences in skeletal and dental effects, as well as any differences in condylar/TMJ adaptation associated with each appliance design.
Interventions
DEVICEConventional Twin Block Appliance
A removable functional appliance consisting of upper and lower acrylic occlusal bite blocks used to advance the mandible and correct skeletal class II malocclusion in growing patients
Sponsors
Al-Azhar University
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
Two parallel groups: fixed Twin Block appliance versus conventional Twin Block appliance.
Eligibility
Sex/Gender
MALE
Age
11 Years to 15 Years
Healthy volunteers
Yes
Inclusion criteria
1. Growing male patients (as judged from clinical examination and confirmed later by (CVM) 2. Skeletal class II with retrognathic mandible. 3. Healthy compliant and motivated patient. 4. No Previous orthodontic treatment. 5. No Severe facial asymmetry determined by clinical or radiographic examination. 6. No Systemic diseases that may affect the treatment results. 7. No tmj disorders.
Exclusion criteria
1. Previous orthodontic treatment. 2. Poor oral hygiene. 3. Severe facial asymmetry determined by clinical or radiographic examination. 4. Systemic disease that may affect the treatment results. 5. TMJ disorders.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Sagittal Skeletal Relationship (ANB Angle) | Measured at baseline (pre-treatment) and at the end of active treatment (approximately 12-18 months, based on actual treatment duration) | Measured using cone beam computed tomography (CBCT), the ANB angle reflects the anteroposterior relationship between the maxilla and mandible. Pre-treatment and post-treatment values will be compared between the fixed and conventional Twin Block appliance groups to assess skeletal correction of Class II malocclusion. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Sagittal Skeletal Relationship (ANB Angle) | Measured at baseline (pre-treatment) and at the end of active treatment (approximately 12-18 months, based on actual treatment duration) | Measured using cone beam computed tomography (CBCT), the ANB angle reflects the anteroposterior relationship between the maxilla and mandible. Pre-treatment and post-treatment values will be compared between the fixed and conventional Twin Block appliance groups to assess skeletal correction of Class II malocclusion. |
| Change in Condylar Position and TMJ Disc Space | Measured at baseline (pre-treatment) and at the end of active treatment (approximately 12-18 months, based on actual treatment duration) | Measured using cone beam computed tomography (CBCT), condylar position within the glenoid fossa will be assessed by evaluating anterior, superior, and posterior joint spaces. TMJ disc space measurements will also be recorded to evaluate condylar remodeling and adaptation. Pre-treatment and post-treatment values will be compared between the fixed and conventional Twin Block appliance groups. |
Countries
Egypt
Outcome results
None listed