Clinical trial NCT03824574: Cephalometric Evaluation of a Clear Mandibular Advancement Appliance Based on the Twin-block Design
Official title: Cephalometric Evaluation of a Clear Mandibular Advancement Appliance Based on the Twin-block Design
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Skeletal Malocclusion
Keywords: Functional appliance
skeletal class II
mandibular deficiency
twin-block
Growing patients
Clear appliance
Aligner
Lead sponsor: Ain Shams University
Sponsor class: OTHER
First posted: 2019-01-31
Enrollment: 20
Sex: FEMALE
Minimum age (years): 8
Maximum age (years): 12
Standard ages: CHILD
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: This study evaluates the cephalometric effects of a clear mandibular advancement appliance for the treatment of skeletal class II growing patients suffering from mandibular deficiency.

Detailed description: A Clear mandibular advancement appliance is constructed comprised of a clear dental splint of 1.5 mm thickness adapted on the patient's teeth. This is followed by the construction of acrylic bite ramps bonded over the splints. The bite ramps are constructed as such when the patient bites into occlusion, he/she has to advance the mandible to bring the two parts of the appliance together. Lateral cephalometric radiographs were obtained pre and post-treatment to evaluate the effects on the patient's maxilla, mandible and dentition.

Eligibility criteria: Inclusion Criteria:

1. Gender: Female subjects.
2. Chronological age: All recruited subjects were between the ages of 8-12 years.
3. Anteroposterior skeletal relationship: Subjects with skeletal Class II malocclusion with normal maxilla and retrognathic mandible were selected. This was confirmed using lateral cephalometric radiographic analysis with the following parameters: decreased effective mandibular length (Co-Gn) according to McNamara composite , SNB\<78, SNA=82+2.
4. Dental characteristics:

   * Angle Class II molar relationship ranging from edge to edge to full unit Class II.
   * Overjet ranging between 5-10 mm.
   * Absence of posterior crossbite and/or tendency for posterior crossbite.
5. Skeletal maturation stage: The growth stage for all subjects was selected to be before or at the prepubertal growth spurt. This was confirmed by cervical vertebral maturation analysis from the lateral cephalometric radiograph. The cervical vertebrae maturation stage required was Cervical Vertebrae Maturation stage 2-3 according to the cervical vertebrae maturation index by Baccetti et al. allowing sufficient time before the end of the growth spurt.
6. No previous history of orthodontic treatment.
7. Absence of systemic diseases affecting growth or craniofacial development. -

Exclusion Criteria:

-

Primary outcomes:
measure: Effective Mandibular Length
timeFrame: 12 months
measure: Mandible to cranial base
timeFrame: 12 months
measure: Effective maxillary length
timeFrame: 12 months
measure: Maxilla to cranial base
timeFrame: 12 months
Secondary outcomes:
measure: Lower incisor inclination
timeFrame: 12 months
measure: Lower incisor AP position
timeFrame: 12 months
measure: Upper incisor inclination
timeFrame: 12 months
measure: Upper incisor AP position
timeFrame: 12 months
measure: Profile convexity
timeFrame: 12 months
measure: Lip protrusion
timeFrame: 12 months
measure: Chin position
timeFrame: 12 months
Other outcomes:
Locations:
Study officials:
References:
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