***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: PURPOSE This study aim ed to quantify the costs of complete denture fabrication by a simplified method compared with a conventional protocol . MATERIAL S AND METHODS A sample of edentulous patients needing conventional maxillary and m and ibular complete dentures was r and omly divided into group S , which received dentures fabricated by a simplified method , and group C , which received conventionally fabricated dentures . We calculated direct and indirect costs for each participant including unscheduled procedures . This study assessed 19 and 20 participants allocated into groups S and C , respectively , and comparisons between groups were conducted by the Mann-Whitney and Student 's t-test ( α = 0.05 ) . RESULTS Complete denture fabrication dem and ed median time periods of 173.2 and 284.5 minutes from the operator for groups S and C respectively , and 46.6 and 61.7 minutes from the dental assistant ( significant differences , p < 0.05 ) . There was no difference between groups regarding postinsertion adjustments . Group S showed lower values for costs with material s and time spent by patients than group C during the fabrication stage , but not during adjustments . CONCLUSIONS The median direct cost of complete denture treatment was 34.9 % lower for the simplified method . It can be concluded that the simplified method is less costly for patients and the health system when compared with a conventional protocol for the rehabilitation of edentulous patients Flaws in the design , conduct , analysis , and reporting of r and omised trials can cause the effect of an intervention to be underestimated or overestimated . The Cochrane Collaboration ’s tool for assessing risk of bias aims to make the process clearer and more Previous papers in this series on evidence -based dentistry have discussed the first 2 steps in seeking answers to clinical problems formulating a clear question and strategically search ing for evidence . The next step , critical appraisal of the evidence , is made easier if one underst and s the basic concepts of clinical research design . The strongest design , especially for questions related to therapeutic or preventive interventions , is the r and omized , controlled trial . Questions relating to diagnosis , prognosis and causation are often studied with observational , rather than experimental , research design s. The strongest study design should be used whenever possible . Rules have been established to grade research evidence . This paper , the fourth in the series , presents an overview of research methodology most commonly used in the dental literature OBJECTIVES To compare subjective and objective outcomes of complete dentures fabricated with st and ard clinical protocol s , but omitted selected steps during the laboratory phase . MATERIAL S AND METHODS Forty-three edentulous patients ( mean age 58.1 years , SD 9.9 , range 35 - 78 ) , were consecutively recruited and r and omly assigned to one of four groups according to selected variations of laboratory steps : Group 1 ( n=10 ) , omission of secondary casts obtained from impressions in border moulded custom trays ; Group 2 ( n=10 ) , omission of secondary casts and face-bow articulator mounting ; Group 3 ( n=10 ) , omission of face-bow mounting ; Group 4 ( n=13 ) , no steps omitted ( control ) . Clinical procedures for all groups were identical , and performed by senior dental students under supervision of prosthodontists , all of whom were blinded to the Group . At 1- , 4- and 12-weeks after delivery , patients rated their overall satisfaction , as well as a range of functional factors using visual analogue scales . An independent blinded prosthodontist similarly rated four domains of denture quality at the 1-week follow-up . RESULTS No significant differences were noted among the groups in all aspects of patients ' assessment s at all the time points ( P>0.1 ) . There were no significant differences in prosthodontists ' ratings of denture quality in any of the domains examined ( P>0.1 ) . CONCLUSION Selected omissions of steps ( face-bow mounting and /or secondary casts ) during the laboratory phase of complete denture fabrication has only a minor role , if any , in subjective and objective outcomes , contrasting with the common belief that such omissions will adversely affect outcomes . CLINICAL SIGNIFICANCE General practitioners provide most complete dentures . Many do not follow all the procedures they were taught at dental school . Our finding that omitting frequently advocated steps made no difference to patient satisfaction or to denture quality suggests that cost-effectiveness through simplifications be considered in practice and in education OBJECTIVES To compare a simplified method to a conventional protocol for complete denture fabrication regarding  masticatory performance and ability . METHODS A sample was formed by edentulous patients requesting treatment with maxillary and m and ibular complete dentures . Participants were r and omly divided into two groups : Group S , which received dentures fabricated by a simplified method , and Group C ( n=21 each ) , which received conventionally fabricated dentures . After three months following insertion , masticatory performance was evaluated by a colorimetric assay based on chewing two capsules as test food during twenty and forty cycles . Masticatory ability was assessed by a question naire with binary answers and a single question answered by means of a 0 - 10 scale . A third group ( DN ) formed by seventeen dentate volunteers served as an external comparator . Groups were compared by statistical tests suitable for data distribution ( α=0.05 ) . RESULTS Thirty-nine participants were assessed for three months ( twenty from Group C and nineteen from Group S ) . Groups C and S presented similar masticatory performance which corresponded to approximately 30 % of Group DN . Results for masticatory ability showed similarity between S and C , regardless of the assessment method , although an isolate question naire item showed more favourable results for the first group . CONCLUSIONS The simplified method for complete denture fabrication is able to restore masticatory function to a level comparable to a conventional protocol , both physiologically and according to patient 's perceptions . CLINICAL SIGNIFICANCE Although masticatory function is impaired by the loss of natural teeth and dentures can restore only a fraction of such function , patients can benefit from a simplified protocol for complete denture fabrication to the same extent they would by conventional techniques PURPOSE Conventional dentures will remain the only treatment available to most edentulous people for the foreseeable future . In this study , we compared the efficiency of two methods of making complete conventional dentures-the traditional academic st and ard ( T ) and a simplified technique ( S ) used in private practice . We have previously shown that they produce similar levels of patient satisfaction and denture quality . MATERIAL S AND METHODS Data were gathered during a r and omized controlled clinical trial of 122 subjects from initial examination until 6-month follow-up . For this report , the direct costs of providing one set of conventional complete dentures by T or S techniques were estimated . All material s used were recorded and their cost was calculated in Canadian dollars ( CAN$ ) . The costs of fabrication in an outside laboratory were added . Clinician 's labor time was recorded for every procedure . Between-group comparisons for each clinical procedure were carried out with independent t-tests . The number of patients in each group who needed postdelivery treatment was compared with Chi-square tests . The effect of group assignment and of treatment difficulty on outcomes was analyzed with multiple regression analysis . RESULTS The mean total cost of the T method was significantly greater than S ( CAN$166.3 ; p < 0.001 ) , and clinicians spent 90 minutes longer ( p < 0.001 ) on clinical care . The difficulty of the case had no significant influence on outcomes . CONCLUSIONS The results indicate that the S method is the more cost-efficient method and that there are no negative consequences that detract from the cost savings OBJECTIVES The objective of this r and omised controlled clinical trial study was to compare the effectiveness of a traditional and a simplified protocol for construction of conventional CD . BACKGROUND The replacement of conventional dentures can result in potential functional and aesthetic benefits to the patient . Previous studies suggest that simplified procedures for complete dentures ( CD ) construction achieve results similar to the traditional methods . MATERIAL S AND METHODS Fifty patients were r and omly divided into two equal groups , traditional protocol ( T group ) and simplified protocol ( S group ) . Treatment outcomes were assessed before the insertion of the new dentures and 30 days and 6 months after the last adjustment . It included measurements of quality of life related to oral conditions measured by the Brazilian version of OHIP-Edentulous scale and patients ' satisfaction with the upper and lower dentures using a visual analogue scale ( VAS ) , which combines the patient 's perception in relation to overall satisfaction with the comfort , stability , ability to chew , ability to talk and aesthetics . RESULTS The results showed significant reduction in negative impacts of oral conditions on quality of life and improved satisfaction with the upper and lower dentures ( p < 0.001 ) at the 30-day and 6-month follow-up . Quality of life improvement occurred in all dimensions of the OHIP-Edentulous ( p < 0.001 ) . Despite the significant reduction in quality of life impacts and significant increase in patients ' satisfaction with the dentures , there were no differences between the traditional and simplified protocol s ( p > 0.05 ) . CONCLUSIONS It was concluded that the simplified protocol results in patent 's perception of treatment outcomes similar to the traditional protocol OBJECTIVES To compare the quality of conventional complete dentures fabricated with two different techniques . A r and omized controlled clinical trial was conducted to compare traditional ( T ) and simplified ( S ) methods of making complete conventional dentures on patients ' ratings of satisfaction , comfort and function at 3 and 6 months following delivery . The quality of the prostheses was rated by prosthodontists at 6 months . MATERIAL S AND METHODS One hundred twenty-two male and female edentulous individuals , aged 45 - 75 years , were r and omly allocated into groups that received dentures made with either T or S methods . Following delivery , patients ' ratings of several denture-related factors were measured using 100 mm visual analogue scales , and denture quality was assessed by blinded prosthodontists using ratings on a vali date d quantitative scale . RESULTS There were no significant differences between the two groups in patient ratings for overall satisfaction ( 3 months : mean T = 83 mm , mean S = 83 mm , P = 0.97 ; 6 months : mean T = 79 mm , mean S = 79 mm , P = 0.96 ) or in prosthodontists ' ratings of denture quality ( T = 66 , S = 63 ; P = 0.38 ) . CONCLUSION These results show that the quality of complete dentures does not suffer when manufacturing techniques are simplified to save time and material s. Dental educators should consider these findings when re- design ing prosthodontic training programs 
    Output:
    
The clinical studies considered for this review suggest that a two-step impression procedure may not be m and atory for the success of conventional complete denture fabrication regarding a variety of clinical aspects of denture quality and patients ' perceptions of the treatment