***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: Therapeutic trials often attempt to “ blind ” patient and investigator to the true nature of treatments received , reducing the influences of conscious or subconscious prejudices . In drug trials , this is accomplished with placebo tablets , but blinding in trials of physical treatments is more problematic . This issue arose in a clinical trial of transcutaneous electrical nerve stimulation ( TENS ) for patients with chronic low back pain . Several study design features were incorporated to promote blinding : use of sham TENS units visually identical with real units , exclusion of potential subjects with previous TENS experience , avoidance of a crossover design and use of identical visit frequency , instructions and modifications in electrode placement . Subjects were asked not to discuss treatments with the clinicians who performed outcome assessment s. Both patients and clinicians were asked to guess actual treatment assignments at the trial 's end . Every patient in the true TENS group believed the unit was functioning properly , but the degree of certainty varied . In the sham TENS group , 84 % also believed they had functioning units , but their certainty was significantly less than in the active treatment group . Differences in patient perceptions did not affect compliance , as the two groups had similar dropout rates , appointment compliance , days of TENS use and daily duration of TENS use . Clinicians guessed treatments correctly 61 % of the time ( as opposed to 50 % expected by chance ) , again suggesting partial success in blinding . These efforts at blinding may partly explain the negative trial results for TENS efficacy . We conclude that complete blinding is difficult to achieve because of sensory difference in treatment and unintended communication between patient and examiner . Nonetheless , trials of physical treatments can achieve partial blinding with the techniques described here , and the success of blinding can be assessed with simple questions at study completion The EBN users ’ guide in the previous issue of Evidence -Based Nursing outlined the primary and secondary questions for evaluating studies of healthcare interventions . One of the primary questions for assessing the validity of a study ’s findings is whether the assignment of patients to treatments was r and omised and whether r and omisation was concealed . One of the secondary questions is whether patients , clinicians , outcome assessors , and data analysts were unaware of ( blinded to or masked from ) patient allocation . Beginning with the October 1999 issue of Evidence -Based Nursing , allocation concealment and blinding have been given more attention . The “ design ” section of abstract s of r and omised trials now includes a statement of whether r and omisation was concealed from those responsible for entering patients into trials , and who was blinded to treatment allocation during the trials . These additional specifications provide readers with more information to judge the internal validity of trials . In this editorial , the background and rationale for these decisions are addressed In r and omised controlled trials , allocation concealment ( separating the process of r and omisation from the recruitment of participants ) is important for rigorously design ed trials.1–4 In 1996 many major medical journals adopted the CONSORT statement ( whereby research ers have to include a short checklist of essential items and a flow diagram when reporting trials),5 and this move encouraged the reporting of allocation concealment . We review ed the prevalence of adequate allocation concealment and its association with the statistical significance of trial results . We search ed by h and four general medical journals ( the BMJ , JAMA , the Lancet , and the New Engl and Journal of Medicine ) to identify r and omised controlled trials published from January 2002 to December 2002 . We included articles if the authors reported that participants were r and omised and if the trial was published as a full report with the results of the main analyses . We categorised articles according to whether allocation concealment was adequate ( the person who executed the allocation sequence was different from the person who recruited BACKGROUND , AIMS The purpose of the present study was to compare the efficacy of 3 different surgical procedures in the treatment of infrabony defects :  guided tissue regeneration ( GTR ) with non-resorbable membranes , Widman modified flap ( WMF ) and enamel matrix derivative ( EMD ) . METHOD 30 patients with an infrabony component > or = 4 mm were selected . 10 were treated with exp and ed polytetrafluorethylene ( ePTFE ( Gore - Tex W. L. Gore and Associates , Flagstaff , AZ , USA ) ) membranes , 10 with WMF and 10 with enamel matrix derivatives ( Emdogain ( U Biora AB Malm , Sweden ) ) . The efficacy of each treatment modality was investigated through regression analysis . Probing attachment level ( PAL ) gain , probing depth ( PD ) reduction and gingival recession ( REC ) variation were analyzed . RESULTS Both Emdogain ( enamel matrix derivative ) and ePTFE treatment show significant better results as compared to the WMF procedure in which there were no significant changes in PAL gain and PD reduction at baseline and 1 year after surgery . CONCLUSIONS Results from our analysis suggest that there is no statistically significant difference in PAL gain between GTR and EMD . The clinical outcomes of this pilot study may be of little significance , considering the small number of patients , but it has provided an important base for a controlled clinical trial ( with a larger number of patients ) which is currently in progress BACKGROUND Several studies have documented the clinical efficacy of guided tissue regeneration ( GTR ) with non-resorbable exp and ed polytetrafluoroethylene ( ePTFE ) membranes and enamel matrix proteins ( EMP ) in the treatment of infrabony defects . The objective of this controlled clinical study was to compare the clinical outcomes of 3 surgical modalities in the treatment of deep interproximal infrabony defects . METHODS Ninety ( 90 ) defects in 90 healthy subjects affected by chronic periodontitis were assigned to 1 of 3 treatment groups by blocking to prognostic variables . The test group was treated with the application of EMP and the simplified papilla preservation ( SPP ) technique ; the second group was treated with titanium-reinforced ePFTE membranes and the SPP technique ; and the third group was treated with the SPP technique used as access flap control procedure . No differences were observed in terms of baseline oral hygiene and defect characteristics among the 3 groups , indicating that the blocking approach was effective . A stringent infection control program was adopted for 1 year . RESULTS The 1-year results indicated that : 1 ) all treatment modalities result ed in clinical ly significant improvements in clinical attachment levels ( CAL ) and reduction in probing depth ( PD ) ; 2 ) a statistically significant treatment effect was demonstrated comparing the EMP test , the membrane control , and the flap control groups in terms of CAL gains ; 3 ) both the EMP test and the membrane control groups showed significant CAL gains compared to the flap control group ; 4 ) a statistically significantly greater amount of CAL gain was demonstrated in GTR-treated compared to EMP-treated patients ; 5 ) deeper residual probing depths but smaller increases in gingival recession were demonstrated following EMP therapy ; and 6 ) smoking habits reduced the clinical outcomes of both regenerative procedures . CONCLUSIONS The use of a regenerative procedure is indicated in the treatment of deep vertical bony defects since both the regenerative techniques ( GTR and EMD ) in the present study result ed in clinical ly and statistically significant improvements in clinical parameters compared to the access flap procedure . The use of EMP can be helpful in esthetically-sensitive sites and in reducing patient morbidity Although the r and omized controlled trial is the most important tool currently available to objective ly assess the impact of new treatments , the act of r and omization itself is often poorly conducted and incompletely reported . The primary purpose of r and omizing patients into treatment arms is to prevent research ers , clinicians , and patients from predicting , and thus influencing , which patients will receive which treatments . This important source of bias can be eliminated by concealing the upcoming allocation sequence from research ers and participants . Although there are many approaches to r and omization that are known to effectively conceal the r and omization sequence , the use of sequentially numbered , opaque sealed envelopes ( SNOSE ) is both cheap and effective . The purpose of this tutorial is to describe a step-by-step process for the preparation of SNOSE . We will outline how to prepare SNOSE to preserve allocation concealment in a trial that ( a ) uses unrestricted ( simple ) r and omization , ( b ) stratifies r and omization on one factor , ( c ) uses permuted blocks and , and ( d ) is conducted at more than 1 study site PURPOSE R and omized trials provide essential evidence of the effect of interventions in oral health . Such trials need to be appraised by readers in order to decide whether to incorporate new findings into clinical practice and policy in a timely manner . The CONSORT ( Consoli date d St and ards of Reporting of Trials ) Statement is a guidance to facilitate reporting of r and omized controlled trials ( RCTs ) and was first introduced in 1996 . The purpose of this article is to highlight the importance of rigorous reporting of trials in oral health and to discuss the impact of CONSORT on trial reporting . RESULTS Empirical studies demonstrate that key aspects of trial methods influence the size of estimates of studied interventions and bias is a plausible mechanism for some of this effect . Complete and transparent reporting of these methods allows appraisal of the value of trials to be undertaken and the potential for bias to be estimated . Systematic review s have shown that the reported quality of trials in dentistry is poor , thus hindering the underst and ing of the value of individual trials . Since 1996 , CONSORT has been adopted by hundreds of medical journals , international editorial groups , and five dental journals . A systematic review has shown that the quality of reporting of trials improves in journals that have adopted this guidance , although with significant variation , most likely due to differing levels of editorial adherence to it The criteria and scoring method for a system to evaluate the quality of  r and omized control trials ( RCTs ) in dental research based on published reports is presented . This sytem is based on one devised for evaluation of RCTs in medicine . Items assessed in this system include r and omization and blinding procedures , subject selection criteria , treatment protocol s , and statistical analyses . Assessing the quality of RCTs can contribute to improved study design , implementation and reporting by investigators , and evaluation of reports by referees and editors of scientific journals OBJECTIVE To evaluate the effects of local-delivery of 25 % metronidazol gel and mechanical cleaning using ultrasonic carbon fiber tip on dental implants with peri-implantitis . METHODS 27 implants with peri-implantitis were r and omly assigned to receiving either 25 % metronidazol gel treatment or carbon fiber tip ultrasonic scaling . All parameters including plaque index ( PLI ) , probing depth ( PD ) of pocket , sulcular bleeding index ( SBI ) , and BANA enzyme analysis were measured at baseline , 1 , 2 , 6 and 12 weeks after treatment . RESULTS Statistically significant decrease ( P < 0.05 ) in SBI , BANA test and PLI occurred in both treatment groups at all time intervals compared to baseline . PD had a decreasing tendency in both groups , but only metronidazole group reached statistically significant level ( P < 0.05 ) at 2 and 6 week intervals compared to baseline . None of the treatment modalities produced any side effects on the implant and peri-implant tissues . CONCLUSIONS Both 25 % metronidazol gel and mechanical cleaning using ultrasonic carbon fiber tip can be safely and effectively used in the treatment of peri-implant diseases UNLABELLED In the present prospect i ve clinical trial , the effect of various regenerative procedures performed at sites with angular bone defects were evaluated . The main outcome variable was probing attachment alteration . MATERIAL AND METHODS 40 subjects , aged 32 - 61 years participated . They met the following inclusion criteria : ( i ) presence of generalized , advanced periodontal tissue destruction ; ( ii ) presence of 2 similar , contralateral , angular bone defects ( experimental sites ) located in either the maxilla or the m and ible ; ( iii ) the defect site must exhibit a probing pocket depth ( PPD ) of > or = 6 mm , a probing attachment level ( PAL ) of > or = 7 mm , and a depth of the intrabony component of > or = 3 mm . All subjects had a good oral hygiene st and ard , were in good general health and did not use any medication . Prior to the start of the study , all subjects received non-surgical treatment for periodontal disease .  Baseline clinical measurements ( plaque , gingivitis , PPD , PAL and soft tissue recession ) of the selected experimental sites were obtained 6 months after the completion of basic therapy . The 40 subjects were r and omly divided into 4 treatment groups including 10 subjects each : 3 membrane groups and one Emdogain group . 1 h before surgery , the patients were given 3 g of Amoxicillin . No other antibiotics were prescribed . The test and control sites were treated during the same surgical session . Full thickness flaps were elevated and the exposed root surfaces were planed . Membrane placement : The root surface was rinsed with saline . A barrier membrane ( Guidor or Resolut or Periodontal ( e-PTFE ) material ) was positioned to cover the defect and the adjacent 2 - 3 mm of bone tissue . The control treatment was identical to the test treatment with the exception of barrier placement . Emdogain placement : The exposed root surfaces at both the test and control sites were , during a 2-min period , conditioned with a 24 % EDTA gel . Emdogain was applied to the exposed root surface of the test site . In the control site , the vehicle , the PGA gel , was used as placebo control . The flaps were closed and sutured to obtain a complete coverage of the intrabony defect . RESULTS Re-examinations , which were performed 12 months after surgery , disclosed that regenerative therapy , including either the use of barrier membranes or application of enamel matrix proteins to an instrumented root surface in an angular , intrabony defect , enhanced outcome variables such as probing pocket depth and probing attachment gain . It was furthermore demonstrated that clinical improvements were better at sites 
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There were no statistically significant differences in the magnitude of treatment outcomes comparing adequate versus inadequate or unclear allocation concealment , nor comparing adequate and inadequately examiner masked trials .
However , a retrospective power calculation indicated 265 RCTs would be needed to demonstrate a statistically significant effect for the impact of bias on CAL as an outcome measure for a 0.5 mm exaggeration of mean difference between test and control .
There is insufficient evidence to support or refute the theory that the bias from improper methods of allocation concealment and examiner masking affect the magnitude of clinical outcomes in periodontology trials .