Physical properties of root cementum: Part 27. Effect of low-level laser therapy on the repair of orthodontically induced inflammatory root resorption: A double-blind, split-mouth, randomized controlled clinical trial

摘要

IntroductionThe purpose of this 2-arm-parallel split-mouth trial was to investigate the effect of low-level laser therapy (LLLT) on the repair of orthodontically induced inflammatory root resorption (OIIRR). MethodsTwenty patients were included in this study, with 1 side randomly assigned to receive LLLT, and the other side served as a sham. Eligibility criteria included need for bilateral maxillary first premolar extractions as part of fixed appliance treatment. OIIRR was generated by applying 150?g of buccal tipping force on the maxillary first premolars for 4?weeks. After the active force was removed, the teeth were retained for 6?weeks. LLLT commenced with weekly laser applications using a continuous beam 660-nm, 75-mW aluminum-gallium-indium-phosphorus laser with 1/e2spot size of 0.260?cm2, power density of 0.245?W/cm2, and fluence of 3.6?J/cm2. Contact application was used at 8 points buccally and palatally above the mucosa over each tooth root for 15?seconds with a total treatment time of 2?minutes. After 6?weeks, the maxillary first premolars were extracted and scanned with microcomputed tomography for primary outcome OIIRR calculations. Subgroup analysis included assessment per root surface, per vertical third, and sites of heaviest compressive forces (buccal-cervical and palato-apical). Randomization was generated usingwww.randomization.com, and allocation was concealed in sequentially numbered, opaque, sealed envelopes. Blinding was used for treatment and outcome assessments. Two-tailed pairedttests were used to determine whether there were any statistically significant differences in total crater volumes of the laser vs the sham treated teeth. ResultsTotal crater volumes were 0.746?mm3for the laser treated teeth and 0.779?mm3for the sham. There was a mean difference of 0.033?±?0.39?mm3(95% CI, ?0.21 to 0.148?mm3) greater resorption crater volume in the sham group compared with the laser group; this was not statistically significant (P?=?0.705). No harm was observed. Conclusions: No significant difference was found between LLLT and sham control groups in OIIRR repair.