***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 prospect i ve , r and omized , clinical study was to assess the effect of photobiomodulation therapy ( PBM ) with low-level laser irradiation ( LLLI ) on postoperative pain after endodontic treatment . Material s and methods Sixty patients , diagnosed with irreversible pulpitis in lower molar teeth , participated in the study . All treatments were performed by a single operator . Participants were r and omly divided into two groups : in the experimental group ( EG ) , endodontic treatment was performed with a reciprocating system , immediately followed by PBM with LLLI ; and only endodontic treatment was performed in the control group ( CG ) . Postoperative pain was assessed by a second examiner , who was blinded , using two scales : verbal rating scale ( VRS ) and numerical rating scale ( NRS ) . Assessment was carried out at 6 , 12 , and 24 h after treatment . Data were analyzed using chi-squared , Fisher ’s exact , Mann-Whitney tests , ordinal , and non-parametric regression analyses . Results For the prevalence of pain , the difference between the groups was significant for the evaluations performed after 6 h ( p = 0.04 ) and 24 h ( p = 0.02 ) . The difference after 24 h remained significant after stratification by sex and extrusion of filling material . Increased pain intensity was associated with extrusion of root canal filling material to the periapical region in the two scales used . Conclusion The effect of PBM therapy after endodontic treatment showed a significant decreasein prevalence of postoperative pain . Clinical relevance The PBM reduces the prevalence of postoperative pain and may benefit patients who need endodontic treatment Introduction : The aim of this r and omized clinical trial was to evaluate the influence of rotary or reciprocating retreatment techniques on the incidence , intensity , duration of postoperative pain , and medication intake . Methods : After power analysis calculations , 65 patients who needed endodontic retreatment were r and omly assigned to 1 of 2 groups according to the instrumentation system used : Mtwo ( VDW , Munich , Germany ) or Reciproc ( VDW ) . Retreatments were performed in a single visit by an endodontic specialist . Participants were asked to rate the incidence and intensity of the postoperative pain on a verbal rating scale 24 , 48 , and 72 hours after treatment . Patients were also asked to record the number of prescribed analgesic medication tablets ( ibuprofen 400 mg ) taken . A logistic regression analysis was used to assess both the incidence and duration of pain . Differences in the intensity of pain were analyzed using the ordinal ( linear ) chi‐square test , and the Mann‐Whitney U test was used to assess differences in the intake of analgesic medication between groups . Results : No statistically significant difference was found among the 2 groups in relation to postoperative pain or analgesic medication intake at the 3 time points assessed ( P > .05 ) . Multivariate analysis showed a significantly higher incidence of pain after 24 hours when preoperative pain was present and a significantly longer duration of pain for men than women independently of the retreatment technique used . Conclusions : The reciprocating system and the continuous rotary system were found to be equivalent regarding the incidence , intensity , duration of postoperative pain , and intake of analgesic medication OBJECTIVES The aim of this prospect i ve study was to investigate the correlation between the intensity of preoperative pain and the presence of postoperative pain , taking into account the variables sex , tooth type , arch , and tooth vitality . METHODS Two hundred and seventy patients with pulpal pathology who were scheduled for routine endodontic treatment were enrolled in this study . Conventional endodontic treatment was carried out in a single visit . The chemomechanical preparation of root canals was performed with ProTaper instruments , and canals were obturated with a warm gutta-percha obturation technique . A structured question naire was used to record data on sex , age , type of tooth , location and pulp diagnosis . Patients were asked to record their preoperative and postoperative pain using a 10-cm visual analogue scale ( VAS ) . Postoperative pain and the need for analgesic consumption were assessed at 4 , 8 , 16 , 24 , 48 and 72h post-treatment . The data were analyzed using the Mann-Whitney U and chi-square test , and the significance was set at P<.05 . RESULTS The mean level of pain after root canal treatment was 2.58±2.80 on a VAS between 0 and 10 . Variables that were associated with a higher preoperative pain intensity ( female , m and ible and molar ) also had a higher value of postoperative pain ( P>.05 ) . CONCLUSIONS Within the limitations of this study , it can be concluded that the presence of preoperative pain is the variable that most influences the prevalence of postoperative pain . CLINICAL SIGNIFICANCE Pain management should be an integral part of dental treatment . The present study analyses the incidence of postoperative pain that should be expected by patients with different intensity of pain before root canal treatment Some patients experience severe pain following root canal therapy ( RCT )  despite advancements in care . We sought to identify factors , which can be measured preoperatively , that predict this negative outcome so that future research may focus on preemptive steps to reduce postoperative pain intensity . Sixty-two practitioners ( 46 general dentists and 16 endodontists ) who are members of the National Dental Practice -Based Research Network enrolled patients receiving RCT for this prospect i ve observational study . Baseline data collected from patients and dentists were obtained before treatment . Severe postoperative pain was defined based on a rating of ≥7 on a scale from 0 ( no pain ) to 10 ( pain as bad as can be ) for the worst pain intensity experienced during the preceding week , and this was collected 1 wk after treatment . Multiple logistic regression analyses were used to develop and vali date the model . A total of 708 patients were enrolled during a 6-m period . Pain intensity data were collected 1 wk postoperatively from 652 patients ( 92.1 % ) , with 19.5 % ( n = 127 ) reporting severe pain . In multivariable modeling , baseline factors predicting severe postoperative pain included current pain intensity ( odds ratio [ OR ] , 1.15 ; 95 % confidence interval [ CI ] , 1.07 to 1.25 ; P = 0.0003 ) , number of days in the past week that the subject was kept from their usual activities due to pain ( OR , 1.32 ; 95 % CI , 1.13 to 1.55 ; P = 0.0005 ) , pain made worse by stress ( OR , 2.55 ; 95 % CI , 1.22 to 5.35 ; P = 0.0130 ) , and a diagnosis of symptomatic apical periodontitis ( OR , 1.63 ; 95 % CI , 1.01 to 2.64 ; P = 0.0452 ) . Among the factors that did not contribute to predicting severe postoperative pain were the dentist ’s specialty training , the patient ’s age and sex , the type of tooth , the presence of swelling , or other pulpal and apical endodontic diagnoses . Factors measured preoperatively were found to predict severe postoperative pain following RCT . Practitioners could use this information to better inform patients about RCT outcomes and possibly use different treatment strategies to manage their patients ( Clinical trials.gov NCT01201681 ) BACKGROUND To investigate and compare the post-obturation pain after one-visit and two-visit root canal treatment in non-vital anterior teeth . MATERIAL S & METHODS One hundred forty eight patients requiring root canal therapy on permanent anterior non-vital teeth with single root were included in this study . Patients were r and omly assigned to either the one-appointment or the twoappointment group . The st and ardized protocol for all the teeth involved local anesthesia , isolation and access , engine-driven rotary nickel-titanium canal instrumentation with 2.5 % NaOCl irrigation and obturation . Teeth in group 1 ( n = 74 ) were obturated during the first appointment by using laterally condensed gutta-percha and resin sealer . Teeth in group 2 ( n = 74 ) were given closed dressing and were obturated during the second appointment , 7 to 14 days later . A modified Visual Analogue Scale was used to measure pain after 6 hours , 24 hours , 48 hours and 7 days after the treatment . Statistical analysis was done to compare groups at each interval by using an independent- sample s t test . RESULTS The incidence and intensity of post-obturation pain in both Group ' A ' and Group ' B ' gradually reduced over the study period . When the incidence of pain was compared in the single and two visit group , it was found that the single-visit group experienced slightly less pain than the two-visit group during all study intervals , but the difference found was not statistically significant . CONCLUSION There was no difference in postoperative pain between patients treated in only one appointment and patients treated in two appointments . The majority of patients in both groups reported no pain or only minimal pain after 7 days of treatment . How to cite the article : Rao KN , K and aswamy R , Umashetty G , Rathore VP , Hotkar C , Patil BS . Post-Obturation pain following one-visit and two-visit root canal treatment in necrotic anterior teeth . J Int Oral Health 2014;6(2):28 - 32 Aim The aim of this study was to evaluate the effect of simultaneous length control during root canal preparation on postoperative pain compared with separate working length determination and root canal preparation . The design was a parallel‐group , r and omized , controlled trial with 2 arms . Methods Forty‐four molar teeth were r and omly divided into 2 groups ( n = 22 ) , a control group ( separate length determination and root canal preparation ) and a simultaneous length control during root canal preparation group . The following variables were recorded : age ; gender ; tooth number ; preoperative pain on the visual analog scale ; pain level on days 1 , 3 , 5 , and 7 ; and  analgesic intake after the procedure and initial/final percussion pain . The data were analyzed with the χ2 test , independent sample s t test , and Mann‐Whitney U test . Results The simultaneous length control during root canal preparation group result ed in lower postoperative pain levels on day 1 than did the control group ( P < .05 ) . Despite 2 patients ’ intake of postoperative analgesics in the control group , no patient needed to use postoperative analgesics in the simultaneous length control during root canal preparation group ( P > .05 ) . Conclusions Simultaneous length control during root canal preparation as a non‐pharmacologic strategy for reducing postoperative pain is a beneficial technique for preventing postoperative pain Phototherapy with low-level laser therapy ( LLLT ) and light-emitting diode therapy ( LEDT ) has arisen as an interesting alternative to drugs in treatments of musculoskeletal disorders . However , there is a lack of studies investigating the effects of combined use of different wavelengths from different light sources like lasers and light-emitting diodes ( LEDs ) in skeletal muscle disorders . With this perspective in mind , this study aim ed to investigate the effects of phototherapy with combination of different light sources on nonspecific knee pain . It was performed a r and omized , placebo-controlled , double-blinded clinical trial . Eighty-six patients rated 30 or greater on the pain visual analogue scale ( VAS ) were recruited and included in study . Patients of LLLT group received 12 treatments with active phototherapy ( with 905 nm super-pulsed laser and 875 and 640 nm LEDs , Manufactured by Multi Radiance Medical , Solon , OH , USA ) and conventional treatment ( physical therapy or chiropractic care ) , and patients of placebo group were treated at same way but with placebo phototherapy device .  Pain assessment s ( VAS ) were performed at baseline , 4th , 7th , and 10th treatments , after the completion of treatments and at 1-month follow-up visit . Quality of life assessment s ( SF-36 ® ) were performed at baseline , after the completion of treatments and at 1-month follow-up visit . Our results demonstrate that phototherapy significantly decreased pain ( p < 0.05 ) from 10th treatment to follow-up assessment s and significantly improved ( p < 0.05 ) SF-36 ® physical component summary at posttreatments and follow-up assessment s compared to placebo . We conclude that combination of super-pulsed laser , red and infrared LEDs is effective to decrease pain and improve quality of life in patients with knee pain The purpose of this prospect i ve study was to assess the incidence of flare-ups ( a severe problem requiring an unscheduled visit and treatment ) among patients who received endodontic treatment by the two authors in their respective practice s during a period of one year , and also to examine the correlation with pre-operative and operative variables . The results showed an incidence of 1.58 % for flare-ups from 1012 endodontically treated teeth . Statistical analysis using the chi-square test ( P<0.05 ) indicated that flare-ups were found to be positively correlated with multiple appointments , retreatment cases , periradicular pain prior to treatment , presence of radiolucent lesions , and patients taking analgesic or anti-inflammatory drugs . In contrast , there was no correlation between flare-up , and age , sex , different arch/tooth groups and the status of the pulp Introduction : In this clinical trial , we evaluated the effect of low‐level laser therapy ( LLLT ) on postoperative pain in m and ibular molar teeth with symptomatic apical periodontitis . Methods : Forty‐two patients were included in the study according to the inclusion and exclusion criteria .  Root canal treatment was conducted using reciprocating instruments . The patients were r and om 
    Output:
    
Based on the current evidence , the use of LLLT for pain control in postendodontic therapy may be promising .