***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: INTRODUCTION The purpose of this study was to clinical ly evaluate the effect of low-level laser therapy ( LLLT ) as a method of reducing pain reported by patients after placement of their first orthodontic archwires . METHODS The sample comprised 60 orthodontic patients ( ages , 12 - 18 years ; mean , 15.9 years ) . All patients had fixed orthodontic appliances placed in 1 dental arch ( maxillary or m and ibular ) , received the first archwire , and were then r and omly assigned to the experimental ( laser ) , placebo , or control group . This was a double-blind study . LLLT was started in the experimental group immediately after placement of the first archwire . Each tooth received a dose of 2.5 J per square centimeter on each side ( buccal and lingual ) . The placebo group had the laser probe positioned into the mouth at the same areas overlying the dental root and could hear a sound every 10 seconds . The control group had no laser intervention . All patients received a survey to be filled out at home describing their pain during the next 7 days . RESULTS The patients in the LLLT group had lower mean scores for oral pain and intensity of pain on the most painful day . Also , their pain ended sooner . LLLT did not affect the start of pain perception or alter the most painful day . There was no significant difference in pain symptomatology in the maxillary or m and ibular arches in an evaluated parameter . CONCLUSIONS Based on these findings , we concluded that LLLT efficiently controls pain caused by the first archwire Phototherapy with low-level coherent light ( laser ) has been reported as an analgesic and anti-inflammatory as well as having a positive effect in tissue repair in orthodontics . However , there are few clinical studies using low-level LED therapy ( non-coherent light ) . The aim of the present study was to analyze the pain symptoms after orthodontic tooth movement associated with and not associated with coherent and non-coherent phototherapy .  Fifty-five volunteers ( mean age = 24.1 ± 8.1 years ) were r and omly divided into four groups : G1 ( control ) , G2 ( placebo ) , G3 ( protocol 1 : laser , InGaAlP , 660 nm , 4 J/cm2 , 0.03 W , 25 s ) , G4 ( protocol 2 : LED , GaAlAs , 640 nm with 40 nm full-b and width at half-maximum , 4 J/cm2 , 0.10 W , 70 s ) . Separators were used to induce orthodontic pain and the volunteers pain levels were scored with the visual analog scale ( VAS ) after the separator placement , after the therapy ( placebo , laser , or LED ) , and after 2 , 24 , 48 , 72 , 96 , and 120 h. The laser group did not have statistically significant results in the reduction of pain level compared to the LED group . The LED group had a significant reduction in pain levels between 2 and 120 h compared to the control and the laser groups . The LED therapy showed a significant reduction in pain sensitivity ( an average of 56 % ) , after the orthodontic tooth movement when compared to the control group The effects of soft laser ( low reactive level laser ) on reduction of  pain while undergoing orthodontic treatment was examined in this study . These patients were r and omly separated into 3 groups : non-treated control group ( CG ) , blind irradiation group ( BG ) , and laser irradiated group ( LG ) . The effect of laser irradiation on reduction in pain was analyzed by a question naire given to patients who had been wired with an edgewise appliance of a multi-bracket system for orthodontic therapy . Just after application of the initial wire , LG patients were irradiated with the soft laser from the labial and lingual sites for a total of one minute . Reduction in pain was found in some patients who had been irradiated . In particularly , delay in the pain appearance was noted as compared to the other two control groups 
    Output:
    
We had highlighted in the conclusion that although the heterogeneity and risk of bias of the trial results called for caution , LLLTseemed to be effective in delaying the pain onset , shortening the pain duration , and reducing the average pain intensity .