Effectiveness of Modified Functional Appliance With Expander

University of Baghdad

Status: Active, not recruiting

Conditions: Class II Malocclusion

Treatments: Device: Conventional twin block appliance with expander; Device: Modified twin block appliance with expander

Study type: Interventional

Funder types: Other

Identifiers

NCT06116500

664422

Details and patient eligibility

About

This clinical trial compares the effectiveness of a myofunctional appliance that uses a clear and modified twin block appliance with an expander made from 2mm biocompatible polyethylene terephthalate modified with Glycol thermoplastic material with a conventional twin block appliance with an expander. The trial will be conducted on adolescent patients with class II division 1.

Full description

In a multicenter single-blinded randomized clinical trial study with two-arm parallel groups, a computer random generator will develop a simple randomization with an equal allocation ratio (1:1) and without stratification. The investigator will initially assess the patients for eligibility to be included in the study. Those who will meet the inclusion criteria, the parents will be informed about the nature of the study verbally to get the initial approval for participation. Then they will be provided with the patient information sheet and consent form.

According to the sample size calculation, 48 patients will be recruited (24 for each group), and impressions and lateral cephalometric radiography will be taken before treatment and bite registration then the appliance inserted, and the patient will be checked every two weeks for expansion and every four weeks for overjet recording. The treatment will be continuing for 6 months to take final records. The collected data will include cephalometric evaluation, clinical evaluation, scanned upper model evaluation, and finally patient satisfaction from the appliance.

Data will be analyzed using Statistical Package for Social Sciences for Windows, version 26.0 including descriptive statistic (number, mean, and standard deviation), Reliability statistic (interclass correlation coefficient), and Inferential statistics (independent samples t-test).

Enrollment: 48 estimated patients

Sex: All

Ages: 10 to 13 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

1. Patients' age at the start of treatment: at growth spurt [in stage 2 (Acceleration) - 3 (Transition) of cervical vertebral maturation].
2. Skeletal and dental relationships: skeletal class II with normal maxilla and retrognathic mandible. Moderate to severe dental class II division 1 malocclusion with overjet ≥ 8 mm.
3. Horizontal/normal growth pattern.
4. Convex profile with decreased or normal lower facial height (clinically and radiographically).
5. Well-aligned/mild crowding of maxillary and mandibular dental arches.
6. Good oral health free from caries and periodontal problems at the start of treatment.

Exclusion criteria

1. Patients with vertical growth pattern or backward mandibular rotation tendency.
2. Patients with open bite
3. Patients with obvious facial asymmetry.
4. Patients with orofacial clefting.
5. Patients with bad oral habits.
6. Active periodontal disease.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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48 participants in 2 patient groups

Modified twin block appliance with expander group

Experimental group

Description:

For 24 patients with class II division malocclusion in their growing stages, using a 2 mm biocompatible and rigid PET-G thermoforming material to create two clear appliances for each patient. The material will be adapted separately on maxillary and mandibular casts using a pressure molding vacuum machine. Then, the appliances will be trimmed and finished and transferred to the articulator with the aid of a pre-existing working wax bite. The ramps will be made of cold cure acrylic on the thermoplastic sheets. Next, the expansion screw will be placed in the midline of the maxillary cast, and the maxillary appliance will be split midpalatally to fit the patient's individual needs.

Treatment:

Device: Conventional twin block appliance with expander

Device: Modified twin block appliance with expander

Conventional twin block appliance with expander group

Experimental group

Description:

For 24 patients in a growing stage with class II division 1 malocclusion, these appliances will consist of removable maxillary and mandibular appliances. These will have a labial bow, Adam's clasps on the first molars, ball end clasps with incisal capping and expansion screw. The inclined bite blocks (ramps) will act as a guide to move the mandible forward.

Treatment:

Device: Conventional twin block appliance with expander

Device: Modified twin block appliance with expander