***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: The aim of this r and omized , controlled , double-blind study was to examine how the activation pattern of the masseter muscle changes during natural function when experimental pain is induced in a discrete anterior area of the muscle . In 20 subjects , three bipolar surface electrodes and three intramuscular fine-wire electrodes ( antero-posterior mapping ) were simultaneously attached above and in the right masseter muscle to record the  electromyographic ( EMG ) activity during unilateral chewing before and after infusion of a 0.9 % isotonic and 5 % hypertonic saline bolus in the anterior area of the muscle . The activity of the contralateral masseter muscle was registered by surface electrodes . In addition , the development of pain intensity was quantitatively measured with a numerical rating scale ( NRS ) . While both saline concentrations caused pain , the hypertonic solution evoked stronger pain . The experiments also provided evidence of a significant although differential activity reduction of the ipsilateral masseter muscle in the antero-posterior direction . The activity reduction decreased with increasing distance from the location of the infusion . The results support the idea that the strategy of differential activation protects the injured muscle while simultaneously maintaining optimal function A common question in clinical consultations is : “ For this person , what are the likely effects of one treatment compared with another ? ” The central tenet of evidence based medicine is that this task is achieved by using the best evidence combined with consideration of that person 's individual needs.1 A further question then arises : “ What is the best evidence ? ” Two recent studies in the New Engl and Journal of Medicine have caused uproar in the research community by finding no difference in estimates of treatment effects between r and omised controlled trials and non-r and omised trials . The r and omised controlled trial and , especially , systematic review s of several of these trials are traditionally the gold st and ards for judging the benefits of treatments , mainly because it is conceptually easier to attribute any observed effect to the treatments being compared . The role of non-r and omised ( observational ) studies in evaluating treatments is contentious : deliberate choice of the treatment for each person implies that observed outcomes may be caused by differences among people being given the two treatments , rather than the treatments alone . Unrecognised confounding factors can always interfere with attempts to correct for identified differences between groups . These considerations have supported a hierarchy of evidence , with r and omised controlled trials and derivatives at the top , controlled The aim of the investigation was to compare the effect on signs and symptoms of temporom and ibular disorders ( TMD ) of two different interocclusal appliances . Thirty patients with signs and symptoms of TMD received either a stabilisation splint or a new kind of splint based on the concept of nociceptive trigeminal inhibition ( NTI ) . A clinical examination was performed and subjective symptoms were registered before start of treatment and after 3 and 6 months . All participants were offered to change to the other type of splint at the 3-month follow-up in case of no improvement or impairment of their symptoms . One subject in each group was lost early during the investigation . The mean time for taking impressions , to make inter-occlusal recording and to adjust the stabilisation splints was 17 minutes . The mean time to fit and adjust the NTI splints was 27 minutes . At the 3-month follow-up , 4 patients that had received NTI splints accepted the offer to change to stabilisation splints due to no improvement or impairment of their symptoms . These treatments were judged as failures . No one in the stabilisation splint group utilised the offer to change treatment . At the 6-month follow-up , 7 of the remaining 10 subjects with NTI splints reported some ( n = 1 ) or significant ( n = 6 ) improvement , 2 reported no change and one reported impairment . All 14 who had been treated with a stabilisation splint reported some ( n = 2 ) or significant ( n = 12 ) improvement . For all variables registered , the results were in favour for the stabilisation splint . One subject treated with a NTI splint exhibited an impaired occlusion at the 6-month follow-up To assess the diagnostic and behavioural overlap of headache patients with temporom and ibular disorders ( TMD ) , individuals recruited from the general population with self-described headaches were compared with non-headache controls . The examination and diagnostic procedures in the Research Diagnostic Criteria ( RDC ) for TMD were applied to both sets of subjects by a blinded examiner . Following their examination , subjects used experience sampling methods to obtain data on pain , tooth contact , masticatory muscle tension , emotional states and stress . Results showed that a significantly higher proportion of the headache patients received an RDC/TMD diagnosis of myofascial pain than non-headache controls . Headache patients also reported significantly more frequent and intense tooth contact , more masticatory muscle tension , more stress and more pain in the face/head and other parts of the body than non-headache controls . These results are similar to those reported for TMD patients and they suggest that headache patients and TMD patients overlap considerably in diagnosis and oral parafunctional behaviours CONTEXT Despite decades of accumulated observational evidence , the balance of risks and benefits for hormone use in healthy postmenopausal women remains uncertain . OBJECTIVE To assess the major health benefits and risks of the most commonly used combined hormone preparation in the United States . DESIGN Estrogen plus progestin component of the Women 's Health Initiative , a r and omized controlled primary prevention trial ( planned duration , 8.5 years ) in which 16608 postmenopausal women aged 50 - 79 years with an intact uterus at baseline were recruited by 40 US clinical centers in 1993 - 1998 . INTERVENTIONS Participants received conjugated equine estrogens , 0.625 mg/d , plus medroxyprogesterone acetate , 2.5 mg/d , in 1 tablet ( n = 8506 ) or placebo ( n = 8102 ) . MAIN OUTCOMES MEASURES The primary outcome was coronary heart disease ( CHD ) ( nonfatal myocardial infa rct ion and CHD death ) , with invasive breast cancer as the primary adverse outcome . A global index summarizing the balance of risks and benefits included the 2 primary outcomes plus stroke , pulmonary embolism ( PE ) , endometrial cancer , colorectal cancer , hip fracture , and death due to other causes . RESULTS On May 31 , 2002 , after a mean of 5.2 years of follow-up , the data and safety monitoring board recommended stopping the trial of estrogen plus progestin vs placebo because the test statistic for invasive breast cancer exceeded the stopping boundary for this adverse effect and the global index statistic supported risks exceeding benefits . This report includes data on the major clinical outcomes through April 30 , 2002 . Estimated hazard ratios ( HRs ) ( nominal 95 % confidence intervals [ CIs ] ) were as follows : CHD , 1.29 ( 1.02 - 1.63 ) with 286 cases ; breast cancer , 1.26 ( 1.00 - 1.59 ) with 290 cases ; stroke , 1.41 ( 1.07 - 1.85 ) with 212 cases ; PE , 2.13 ( 1.39 - 3.25 ) with 101 cases ; colorectal cancer , 0.63 ( 0.43 - 0.92 ) with 112 cases ; endometrial cancer , 0.83 ( 0.47 - 1.47 ) with 47 cases ; hip fracture , 0.66 ( 0.45 - 0.98 ) with 106 cases ; and death due to other causes , 0.92 ( 0.74 - 1.14 ) with 331 cases . Corresponding HRs ( nominal 95 % CIs ) for composite outcomes were 1.22 ( 1.09 - 1.36 ) for total cardiovascular disease ( arterial and venous disease ) , 1.03 ( 0.90 - 1.17 ) for total cancer , 0.76 ( 0.69 - 0.85 ) for combined fractures , 0.98 ( 0.82 - 1.18 ) for total mortality , and 1.15 ( 1.03 - 1.28 ) for the global index . Absolute excess risks per 10 000 person-years attributable to estrogen plus progestin were 7 more CHD events , 8 more strokes , 8 more PEs , and 8 more invasive breast cancers , while absolute risk reductions per 10 000 person-years were 6 fewer colorectal cancers and 5 fewer hip fractures . The absolute excess risk of events included in the global index was 19 per 10 000 person-years . CONCLUSIONS Overall health risks exceeded benefits from use of combined estrogen plus progestin for an average 5.2-year follow-up among healthy postmenopausal US women .  All-cause mortality was not affected during the trial . The risk-benefit profile found in this trial is not consistent with the requirements for a viable intervention for primary prevention of chronic diseases , and the results indicate that this regimen should not be initiated or continued for primary prevention of CHD STATEMENT OF PROBLEM Patients are often treated for signs and symptoms in the masticatory musculature , which may be manifested as pain and /or conditions that cause difficulty in recording jaw relation records . A quick , easy method to alleviate these signs and symptoms would be helpful . PURPOSE This study measured the effect of a prefabricated anterior bite stop on the electromyographic activity of the anterior temporalis , posterior temporalis , masseter and anterior digastric during clenching , and grinding tasks . MATERIAL AND METHODS A prefabricated anterior bite stop was fabricated for 30 r and omly selected subjects .  Electromyographic surface electrodes were placed on the right and left sides of these muscles . Electromyographic activity was measured during clenching and grinding both with and without the anterior bite stop . RESULTS The anterior bite stop had a significant effect in decreasing electromyographic activity for both clenching and grinding for all the tested muscles , except the anterior digastric . CONCLUSIONS For this patient population , the ready-made anterior bite stop reduced electromyographic muscle activity for the anterior and posterior temporalis and the masseter muscles during both clenching and grinding The nociceptive trigeminal inhibitory ( NTI ) splint has been cl aim ed to decrease the electromyographic ( EMG ) activity of jaw-closing muscles and relieve symptoms of various types of temporom and ibular disorders ( TMD ) and bruxism . The present study was design ed to address the question about EMG-changes during sleep . Ten patients ( age : 23 - 39 years ) with a self-report of tooth-grinding during sleep were recruited . Patients were examined at baseline and after each treatment period with the use of the Research Diagnostic Criteria for TMD . A portable EMG-device was used to record EMG-activity from the masseter muscle during sleep . The patients received two 2-week splint treatments in a r and omized cross-over fashion ; an NTI splint and a st and ard flat occlusal splint ( OS ) .  EMG data were analysed according to published criteria . Using a 10 % of maximum clenching EMG-activity cut-off threshold to determine the number of EMG-events h(-1 ) of sleep , the NTI splint was associated with a significant reduction ( 9.2 + /- 3.2 events h(-1 ) ) compared with baseline EMG ( 19.3 + /- 4.0 ; anova : P = 0.004 , Tukey post hoc : P = 0.006 ) , whereas there were no differences between the OS ( 16.2 + /- 4.7 ) and baseline EMG ( 19.2 + /- 4.1 ; P = 0.716 ) . There were no effects of either NTI or OS on clinical outcome measures ( anovas : P > 0.194 ) . This short-term study indicated a strong inhibitory effect on EMG-activity in jaw closing muscles during sleep of the NTI , but not the OS . However , the EMG-activity was not directly related to clinical outcome . Further studies will be needed to determine long-term effects and possible side effects of the NTI splint Objective . To compare splint therapy in temporom and ibular disorder ( TMD ) patients using two splint design s. Material and methods . In a double-blind r and omized parallel trial , 40 consenting patients were selected from the dental faculty pool of TMD patients . Two splint design s were produced : an ordinary stabilization ( Michigan type ) and a NTI ( Nociceptiv trigeminal inhibition ) . The differences in splint design were not described to the patients . All patients were treated by one operator . A separate , blinded , examiner assessed joint and muscle tenderness by palpation and jaw opening prior to splint therapy , and after 2 and 6 weeks ' and 3 months ' splint use during night-time . The patients reported headache and TMD-related pain on a visual analog scale before and after splint use , and were asked to describe the comfort of the splint and invited to comment . Results . Thirty-eight patients with mainly myogenic problems were observed over 3 months . A reduction of muscle tenderness upon palpation and self-reported TMD-related pain and headache and an improved jaw opening was seen in both splint groups ( p<0.05 ; paired t-test and Wilcoxon signed-ranks tests ) . There were no changes for TM joint tenderness upon palpation . No differences were noted between the two splint design s after 3 months for the chosen criteria of treatment efficacy ( p>0.05 ; Mann-Whitney U-test ) . Conclusion . No differences in treatment efficacy were noted between the Michigan and the NTI splint types when compared over 3 months Dentists and physicians see countless patients suffering from various types of 
    Output:
    
Two RCTs concentrated on electromyographic ( EMG ) investigations in patients with TMDs and concomitant bruxism ( Baad-Hansen et al 2007 , Jadad score : 4 ) or with bruxism alone ( Kavaklı 2006 , Jadad score : 2 ) ; in both studies , compared to an occlusal stabilization splint the NTI-tss device showed significant reduction of EMG activity .
Conclusion Evidence from RCTs suggests that the NTI-tss device may be successfully used for the management of bruxism and TMDs .
The NTI-tss bite splint may be justified when a reduction of jaw closer muscle activity ( e.g. , jaw clenching or tooth grinding ) is desired , or as an emergency device in patients with acute temporom and ibular pain and , possibly , restricted jaw opening