NO CLEAR EVIDENCE FOR THE EFFECT OF LOW-LEVEL LASER TREATMENT ON ORTHODONTICALLY INDUCED INFLAMMATORY ROOT RESORPTION: MORE HUMAN CLINICAL STUDIES ARE NEEDED

Kyungsup Shin

doi:10.1016/j.jebdp.2020.101463

Study Selection Literature search was conducted by the authors using 5 electronically indexed databases (PubMed, Scopus, EMBASE, MEDLINE, and ISI Web of Knowledge) up to September 2018 without language or time restrictions. Studies were selected using the following inclusion criteria: (a) original human clinical studies and animal studies; (b) prospective studies; (c) intervention: effect of low-level laser therapy (LLLT) on orthodontically induced inflammatory root resorption (OIIRR); (d) control group (OIIRR without LLLT); (e) statistical analysis; and (f) tomographic or histologic assessment of OIIRR. Titles and abstracts of the studies identified as described previously were independently screened by two authors, who also independently performed data extraction from the selected studies. A total of 39 studies were identified from the initial database search. Twenty studies were excluded after title and abstract screening and duplicate removal. In addition, 10 studies were excluded after full-text reviews for the following reasons: use of two-dimensional radiograph instead of micro-computed tomography (micro-CT), absence of control group, outcome measured not per se during orthodontic force application, and use of light-emitting diode instead of diode laser. Finally, 9 studies (7 animal studies and 2 human clinical studies) met the eligibility and were included for the systematic review process. Key Study Factor This review included 7 animal studies, in which the key study factor examined was OIIRR evaluated after LLLT treatment during orthodontic tooth movement (OTM). General characteristics of the included studies were summarized in terms of study subjects (eg, rats, dogs, rabbits, and male/female patients), age, number of subjects, study duration, and primary methods of evaluation (eg, micro-CT, histologic, histomorphometric, or immunohistochemical examinations). Study characteristics in orthodontic force applications were summarized in terms of orthodontic appliances, materials, and site of OTM. Lower level laser therapies used in the studies were listed in terms of type of diode laser, wavelength, output power, total energy dose, and administration types such as location, duration, and frequency. Main Outcome Measure In human clinical studies, volumetric differences in root resorption crater were compared between LLLT (experimental group) and placebo-laser (control group) using micro-CT. Both the human clinical studies were doubleblind, split-mouth randomized controlled clinical trials. Orthodontic patients who underwent bilateral maxillary first premolar extractions were treated with LLLT and placebolaser during the OTM after the tooth extractions. In all animal studies, OIIRR was characterized using at least one of the following qualitative evaluation methods: histology, histomorphometry, immunohistochemistry, and scanning electron microscopy. Three animal studies also quantitatively compared severity of OIIRR using micro-CT. Main Results Among 7 animal in vivo studies, 3 studies showed LLLT reduced OIIRR, 3 studies reported increased OIIRR after LLLT, and 1 study found mixed results with regard to the effects of LLLTon repair or prevention for OIIRR. Specifically, 2 in vivo studies showed that LLLT during OTM significantly reduced OIIRR on a rat model. One study reported that LLLT during OTM through alloplastic materials significantly reduced OIIRR on a rabbit model. On the contrary, 2 other animal studies (one on a dog model and the other on a rat model) reported adverse effect of LLLT with increased OIIRR during OTM whether or not combined with corticotomy. The study on a dog model demonstrated that LLLT during OTM through grafted defects increased OIIRR. The study on a rat model found that LLLT was effective in repairing, but not preventing OIIRR. Between the 2 human clinical studies, 1 study showed that LLLT during OTM significantly decreased OIIRR, while the other study found that LLLT after OTM did not significantly affect OIIRR repair. In summary, results from 7 animal studies were equivocal (3 positive, 3 negative, and 1 inconclusive influence of LLLT on OIIRR), and only 1 human clinical study supported the positive effect of LLLT on OIIRR. Conclusions The authors concluded that the influence of LLLT on OIIRR remains unclear and debatable.

NO CLEAR EVIDENCE FOR THE EFFECT OF LOW-LEVEL LASER TREATMENT ON ORTHODONTICALLY INDUCED INFLAMMATORY ROOT RESORPTION: MORE HUMAN CLINICAL STUDIES ARE NEEDED

View Online

Abstract

Details

Metrics