Effect of Low-Intensity Pulsed Ultrasound on Functional Treatment of Class II Malocclusion

Effect of Low-Intensity Pulsed Ultrasound Applied on Temporomandibular Joint Region on Functional Treatment of Class II Malocclusion: A Randomized Controlled Trial

This experimental study will evaluate the effect of combined treatment with low-intensity pulsed ultrasound (LIPUS) and functional appliances (twin-block) on the correction of class II malocclusion, compared with the control group treated with functional appliances (twin-block) only. The study sample will consist of 40 patients with class II malocclusion. The sample will be allocated randomly into two groups: control group and experimental group. The functional appliance (twin-block) will be applied for all patients, while the low-intensity pulsed ultrasound (LIPUS) will be applied for the experimental group only. The skeleto-dental changes occurring after functional treatment will be assessed using cephalometric radiographs; pre and post- treatment changes for each group will be evaluated individually, and the two groups will be compared.

Studies of the etiologic factors of Class II malocclusions recognize that most Class II malocclusions are a result of mandibular deficiency and not of maxillary excess. For many patients, especially adults, optimal overall results are best obtained using a combined orthodontic-surgical approach. However, treating such cases early while the patient is still growing, using mandibular propulsive functional appliances, can produce satisfactory improvement in the facial esthetics, and minimizes the need for surgical intervention in many cases. Ultrasound (US), a form of mechanical energy that is transmitted through and into biological tissues as an acoustic pressure wave at frequencies above the limit of human hearing, is used widely in medicine as a therapeutic, operative and diagnostic tool. Therapeutic US, and some operative US. Previous studies on animals have found that therapeutic ultrasound (US) can stimulate and enhance mandibular growth when applied during the active growth period. This study will evaluate the effect of low-intensity pulsed ultrasound (LIPUS) on the growth of mandible and the duration of functional treatment. Twin-block will be applied to the two groups. While the control group will receive the twin-block only, the experimental group will receive the twin-block combined with low-intensity pulsed ultrasound (LIPUS) on Temporomandibular joint (TMJ) region. Cephalometric radiographs will be obtained before and after functional treatment to evaluate the dento-skeletal changes.

The patients in this experimental group will be treated using the Twin-block combined with LIPUS (Low-intensity pulsed ultrasound).

Dentoskeletal changes before and after functional treatment combined with Low-level Laser compared with those of the control group (SNA, SNB, ANB, Overjet ,…etc) using lateral cephalometric radiographs.

Changes will be evaluated before and after functional treatment which will take approximately 8 months

Inclusion Criteria: Angle class II malocclusion because of mandibular retrognathia O.J > 5 , SNB < 78 Patient during growth spurt Exclusion Criteria: TMJ disorders Poor oral hygiene Previous orthodontic treatment. Patients with syndromes, clefts, or craniofacial abnormalities. Reason of contraindication of functional treatment

The Individual participant data will be only available for the researchers in the department of Orthodontics, Damascus University

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