Investigating the effect of ultrasound on prevention of relapse in severe crouding

Determining the rate of relapse after alignment & leveling in orthodontic patients treated with ultrasound compared to the control group

Clinical trial with a control group, with parallel groups, double-blind, randomized. on 60 patients. The rand function of Excel software was used for randomization.

In this research, 60 patients with class 1 problem with severe crowdingare selected. Patients should undergo fixed orthodontic treatment of both jaws with extraction of the first premolar tooth in both arches. Then the patients are randomly divided into two groups. All patients are molded with alginate at this stage (T0). Then one group is considered as the control group .In the second group, from twenty days before removing the arch wire, there is a low-intensity ultrasound with a frequency protocol of 1 MHz and an intensity of 100 mW/cm² and a duty cycle of 20% (in 1000 cycles per second, 200 us on and 800 us off), frequency 1 KHz And the time of 20 minutes is irradiated to the canine teeth and alveoli of this area in both jaws for 10 sessions in the middle of a day. After this two-month period, the upper and lower jaws are molded from the case and control groups. Molds are cast with orthodontic plaster and are considered as T1.

Patients with 1- systemic disease 2- improper oral hygiene 3- gingivitis or periodontal problems or deep caries that have spread to the cement enamel junction 4- taking drugs that affect bone metabolism such as drugs that prevent bone resorption 5- Conditions for which liposuction is contraindicated, such as (pregnancy, the presence of a malignant lesion in the irradiated area, etc.)

In the intervention group, twenty days before removing the arch wire and after correcting the crowding, the patient is treated with ultrasonic waves.

crowding

Block randomization was done using blocks of 4. For this purpose, we benefited from the PASS 11 software, and thus people were assigned to two groups of 30.

60 patients from the special clinic of Mashhad Faculty of Dentistry, who meet the conditions for entering the study, were included in the study with their consent and were randomly divided into two equal intervention and control groups. For patients in the intervention group, the device was used on, and for the control group, the device was turned off. Patients of both intervention and control groups, as well as the person analyzing the data, were blinded.