Search

Abstract: Orthodontically induced root resorption (OIIRR) is an undesirable consequence of orthodontic treatment and may lead to permanent loss of root structure. A previous clinical trial demonstrated the effect of LIPUS on tipping type of OTM and reported that LIPUS can promote cementogenesis. However, the effect of LIPUS on other types of OTM still remains unclear. Therefore, the aim of this study was to evaluate the effects of LIPUS on OIIRR caused by torque in human subjects. The study sample consisted of 10 healthy human patients between the ages of 12-35 years at the start of the study who required extraction of all first premolars as a part of their routine orthodontic treatment plan. A 15 degree twist was applied in the arch wire using 0.019 x 0.025 TMA wire producing a torque (buccal root) at the bracket level of approximately 5 N-mm. Using a split mouth design, randomization and blinding, one side of the arch received LIPUS for twenty minutes per day for four weeks at an incident intensity of 30mW/cm2 of the transducers surface area. The other side served as a self-control which received a sham transducer. After 4 weeks, all first premolars were extracted for regular orthodontic treatment and a micro-CT analysis was performed of these extracted teeth. Comparison between the two groups was performed using Linear mixed model analysis. LIPUS treated teeth showed significantly less damage compared to control as LIPUS reduced the total volume of resorption lacunae by a mean difference of (0.537 +/- 0.092 mm3) (P