Evaluation of the efficacy of early treatment of skeletal class II patients with twin-block in conjunction with low intensity pulsed ultrasound on temporomandibular joint region: a prospective clinical trial

In this study, twelve male and twelve female children with Class II malocclusion and retrognathic mandible were chosen from the outpatient clinics of the Department of Orthodontics at Al-Azhar University-Boys in Cairo. Their ages varied from nine to twelve.

The patients were split into two groups at random: the low intensity pulsed ultrasound group, which had an average age of 10.55 years, received daily direct application for the first ten days following the placing of the Twin Block appliance, then at least three times a week until mandibular advancement was achieved. LIPUS therapy was administered extra orally on the TMJ region bilaterally using a Sonopower DUO machine, India, LHC-2000.on the right and left sides at the TMJ. Sonication was accomplished by gently massaging the area of interest with 1.5 MHz frequency pulses with a 200-microsecond pulse width, for 20 minutes throughout each session, sonication was repeated at an average intensity of 30 mW/cm2. The control group, which received treatment with a twin block appliance without LIPUS, had an average age of 10.64 years. As part of the authorized orthodontic treatment plan for every patient in the research, the twin block was employed for nine months in both groups.

Prior to and during the Twin Block treatment phase, all patients had CBCT. in addition to the standard orthodontic records. Dentoskeletal measures and TMJ parameters were gathered, recorded, and statistically evaluated to compare changes in the variables within each group and between the two groups.

Version 23 of the SPSS software was used for statistical analysis. A significance criterion of p < 0.05 was established.

Inclusion Criteria:

• Skeletal class II due to retrognathic mandible.
• Angle's class II Molar relationship.
• All patients involved in the study were in stages II and III based on the modified cervical vertebral maturation stages (CVMS) by Bacetti et al.5
• Proclined upper incisors
• Increased overjet > 5 mm.
• Aligned lower arch or average inclination
• Minimal crowding of lower arch.
• No history of previous orthodontic treatment.

Exclusion Criteria:

• Skeletal class II due to prognathic maxilla.
• Patient with gross facial asymmetry.
• Previous orthodontic or orthopedic treatment.
• Clinical signs and symptoms of any Temporomandibular joint disorders.
• Increased anterior facial vertical dimension.
• Poor oral hygiene.