***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: OBJECTIVE The aim of this study was to investigate the effect of low-level laser therapy ( LLLT ) on reducing post-adjustment orthodontic pain  via evaluation of gingival crevicular fluid ( GCF ) composition changes at the level of prostagl and in-E(2 ) ( PGE(2 ) ) and visual analogue scale ( VAS ) . BACKGROUND DATA LLLT has been found to be effective in pain relief . PGE(2 ) has the greatest impact on the process of pain signals and can be detected in GCF in order to investigate the response of dental and periodontal tissues in a biochemical manner . MATERIAL S AND METHODS Nineteen patients ( 11 females and 8 males ; mean age 13.9 years ) were included in this study . Maxillary first molars were b and ed and then a r and omly selected first molar at one side was irradiated ( λ820 nm ; continuous wave ; output power : 50 mW ; focal spot : 0.0314 cm(2 ) ; exposure duration : 5 sec ; power density : 1.59 W/cm(2 ) ; energy dose : 0.25 J ; energy density : 7.96 J/cm(2 ) for each shot ) , while the molar at the other side was served as placebo control . The GCF was collected from the gingival crevice of each molar to evaluate PGE(2 ) levels , before b and placement , 1 and 24 h after laser irradiation . Pain intensity was analyzed at 5 min , 1 h , and 24 h after b and placement by using VAS . RESULTS Although no difference was found in pain perception at 5 min and 1 h , significant reduction was observed with laser treatment 24 h after application ( p<0.05 ) . The mean PGE(2 ) levels were significantly elevated in control group , whereas a gradual decrease occurred in laser group . The difference in PGE(2 ) levels at both 1 and 24 h were statistically significant between two groups ( p<0.05 ) . CONCLUSIONS The significant reductions in both pain intensity and PGE(2 ) levels revealed that LLLT was efficient in reducing orthodontic post-adjustment pain Background : Low level laser therapy ( LLLT ) has gained increasing popularity in the management of tendinopathy and arthritis . Results from in vitro and in vivo studies have suggested that inflammatory modulation is one of several possible biological mechanisms of LLLT action . Objective : To investigate in situ if LLLT has an anti-inflammatory effect on activated tendinitis of the human Achilles tendon . Subjects : Seven patients with bilateral Achilles tendinitis ( 14 tendons ) who had aggravated symptoms produced by pain inducing activity immediately before the study . Method : Infrared ( 904 nm wavelength ) LLLT ( 5.4 J per point , power density 20 mW/cm2 ) and placebo LLLT ( 0 J ) were administered to both Achilles tendons in r and om blinded order . Results : Ultrasonography Doppler measurements at baseline showed minor inflammation through increased intratendinous blood flow in all 14 tendons and measurable resistive index in eight tendons of 0.91 ( 95 % confidence interval 0.87 to 0.95 ) . Prostagl and in E2 concentrations were significantly reduced 75 , 90 , and 105 minutes after active LLLT compared with concentrations before treatment ( p = 0.026 ) and after placebo LLLT ( p = 0.009 ) . Pressure pain threshold had increased significantly ( p = 0.012 ) after active LLLT compared with placebo LLLT : the mean difference in the change between the groups was 0.40 kg/cm2 ( 95 % confidence interval 0.10 to 0.70 ) . Conclusion : LLLT at a dose of 5.4 J per point can reduce inflammation and pain in activated Achilles tendinitis . LLLT may therefore have potential in the management of diseases with an inflammatory component OBJECTIVE To analyze the effect of low-level laser therapy ( LLLT ) on perception of pain after separator placement and compare it with perceptions of control and placebo groups using a frequent irradiation protocol . MATERIAL S AND METHODS Eighty-eight patients were r and omly allocated to a laser group , a light-emitting diode ( LED ) placebo group , or a control group . Elastomeric separators were placed on the first molars . In the laser and LED groups , first molars were irradiated for 30 seconds every 12 hours for 1 week using a portable device . Pain was marked on a visual analog scale at predetermined intervals . Repeated measure analysis of variance was performed for statistical analysis . RESULTS The pain scores of the laser group were significantly lower than those of the control group up to 1 day . The pain scores in the LED group were not significantly different from those of the laser group during the first 6 hours . After that point , the pain scores of the LED group were not significantly different from those of the control . CONCLUSIONS Frequent LLLT decreased the perception of pain to a nonsignificant level throughout the week after separator placement , compared with pain perception in the placebo and control groups . Therefore , LLLT might be an effective method of reducing orthodontic pain 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 OBJECTIVE To test the hypothesis that there is no difference in the pain associated with orthodontic force application after the application of local CO(2 ) laser irradiation to the teeth involved . MATERIAL S AND METHODS Separation modules were placed at the distal contacts of the maxillary first molars in 90 patients in this single-blinded study . In 60 of these patients ( 42 females and 18 males ; mean age = 19.22 years ) this was immediately followed by laser therapy . The other 30 patients ( 18 females and 12 males ; mean age = 18.8 years ) did not receive active laser irradiation . Patients were then instructed to rate their levels of pain on a visual analog scale over time , and the amount of tooth movement was analyzed . RESULTS Significant pain reductions were observed with laser treatment from immediately after insertion of separators through day 4 , but no differences from the nonirradiated control side were noted thereafter . No significant difference was noted in the amount of tooth movement between the irradiated and nonirradiated group . CONCLUSIONS The hypothesis was rejected . The results suggest that local CO(2 ) laser irradiation will reduce pain associated with orthodontic force application without interfering with the tooth movement The aim of this study was to evaluate the pain sensation that orthodontic patients experience when elastic separators are placed between molars and premolars and to determine the degree of analgesic efficacy of low-level laser therapy ( LLLT ) compared to a placebo treatment . The study was conducted with 20 volunteers who were fitted with elastic separators between the maxillary molars and premolars . One quadrant was r and omly chosen to be irradiated with an 830-nm laser , 100 mW , beam diameter of 7 mm , 250 mW/cm2 applied for 20 s per point ( 5 J/cm2 ) . Three points were irradiated in the buccal face and three were irradiated in the palate . The same procedure was applied in the contralateral quadrant with a placebo light . A visual analogue scale was used to assess pain 5 min , 6 h , 24 h , 48 h , and 72 h after placement of the separators . Maximum pain occurred 6–24 h after placement of the elastic separators . Pain intensity was significantly lower in the laser-treated quadrant ( mean , 7.7 mm ) than in the placebo-treated quadrant ( mean , 14.14 mm ; p = 0.0001 ) . LLLT at these parameters can reduce pain in patients following placement of orthodontic rubber separators 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 OBJECTIVE The purpose of this study was to evaluate the efficacy of GaAlAs laser light to reduce pain induced by post-adjustment orthodontic final archwire , compared with a placebo control group , and also to evaluate if there are differences in pain gradient when conventional brackets or self-ligating brackets are used for orthodontic treatment . BACKGROUND DATA Previous reports indicate that laser therapy is a safe and efficient alternative to alleviate pain caused in the initial stages of treatment , but there are no studies about its efficacy during the last stages of orthodontic treatment . METHODS The initial sample was 60 orthodontic patients from a private practice , treated by straight wire technique  , 30 of them with mini brackets Equilibrium ( ® ) ( Dentaurum , Ispringen , Germany ) and 30 with self-ligation In-Ovation C ( ® ) ( GAC/Dentsply , Tokyo , Japan ) slot 0.022 inch brackets . The archwires used in the final stage of orthodontic treatment were stainless steel 0.019 × 0.025 inch , slot 0.022 inch in both groups . In a design of divided mouth , the dental arches were r and omly assigned to receive one dental arch irradiation with 830 nm 100mW therapeutic laser ( Photon Lase II ) , for 22 sec ( 2.2 J , 80 J/cm(2 ) ) along the vestibular surface and 22 sec ( 2.2 J , 80 J/cm(2 ) ) along the palatal surface of the root in the r and omly selected arch . The opposite dental arch received placebo treatment , with the laser light off . Pain was evaluated using a visual analog scale ( VAS ) after 2 , 6 , and 24 h , and 2 , 3 , and 7 days of application . RESULTS The time course of pain showed the same tendency in both groups , reaching a peak 24 h after the archwire activation . The application of laser therapy reduced pain for any period of time up to 7 days ( p<0.00001 ) and for any kind of bracket . CONCLUSIONS Low intensity laser application reduces pain induced by archwires used during the final stage of orthodontic treatment , without any interference regarding the kind of bracket , as reported by patients OBJECTIVE The objective of this study was to evaluate the effectiveness of the use of irradiation with a low-level laser therapy ( LLLT ) , wavelength 830 nm , for treating pain inherent to tooth movement caused by orthodontic devices , simulated by positioning interdental elastomeric separators . METHODS Sixty orthodontic patients were r and omly assigned to two groups : GA ( ages 12 - 25 years ; mean 17.1 years ) was the control , and GB ( ages 12 - 26 years ; mean 17. 
    Output:
    
The selected studies reported promising results for LLLT ; elevated acceleration of tooth movement and lower pain scores , than controls .
With respect to method , there were wide variations in type of laser techniques .
The results highlight the need for high quality research , with consistency in study design , to determine whether LLLT can enhance fixed appliance treatment in children and young adults