title: Research gaps identified during systematic reviews of clinical trials: glass-ionomer cements Direct Contra Naïve-Indirect Comparison of Clinical Failure Rates between High-Viscosity GIC and Conventional Amalgam Restorations: An Empirical Study Pain related to different ways of minimal intervention in the treatment of small caries lesions. Comparison of two tooth-saving preparation techniques for one-surface cavities.
abstract: Background To report the results of an audit concerning research gaps in clinical trials that were accepted for appraisal in authored and published systematic review s regarding the application of glass-ionomer cements ( GIC ) in dental practice Methods Information concerning research gaps in trial precision was extracted , following a framework that included classification of the research gap reasons : ‘ imprecision of information ( results ) ’ , ‘ biased information ’ , ‘ inconsistency or unknown consistency ’ and ‘ not the right information ’ , as well as research gap characterization using PICOS elements : population ( P ) , intervention ( I ) , comparison ( C ) , outcomes ( O ) and setting ( S ) . Internal trial validity assessment was based on the underst and ing that successful control for systematic error can not be assured on the basis of inclusion of adequate methods alone , but also requires empirical evidence about whether such attempt was successful . Results A comprehensive and interconnected coverage of GIC-related clinical topics was established . The most common reasons found for gaps in trial precision were lack of sufficient trials and lack of sufficient large sample size . Only a few research gaps were ascribed to ‘ Lack of information ’ caused by focus on mainly surrogate trial outcomes . According to the chosen assessment criteria , a lack of adequate r and omisation , allocation concealment and blinding/masking in trials covering all review ed GIC topics was noted ( selection - and detection/performance bias risk ) . Trial results appear to be less affected by loss-to-follow-up ( attrition bias risk ) . Conclusion This audit represents an adjunct of the systematic review articles it has covered . Its results do not change the systematic review ’s conclusions but highlight existing research gaps concerning the precision and internal validity of review ed trials in detail . These gaps should be addressed in future GIC-related clinical research Background Naïve-indirect comparisons are comparisons between competing clinical interventions ’ evidence from separate ( uncontrolled ) trials . Direct comparisons are comparisons within r and omised control trials ( RCTs ) . The objective of this empirical study is to test the null-hypothesis that trends and performance differences inferred from naïve-indirect comparisons and from direct comparisons/ RCTs regarding the failure rates of  amalgam and direct high-viscosity glass-ionomer cement ( HVGIC ) restorations in permanent posterior teeth have similar direction and magnitude . Methods A total of 896 citations were identified through systematic literature search . From these , ten and two uncontrolled clinical longitudinal studies for HVGIC and amalgam , respectively , were included for naïve-indirect comparison and could be matched with three out twenty RCTs . Summary effects sizes were computed as Odds ratios ( OR ; 95 % Confidence intervals ) and compared with those from RCTs . Trend directions were inferred from 95 % Confidence interval overlaps and direction of point estimates ; magnitudes of performance differences were inferred from the median point estimates ( OR ) with 25 % and 75 % percentile range , for both types of comparison . Mann-Whitney U test was applied to test for statistically significant differences between point estimates of both comparison types . Results Trends and performance differences inferred from naïve-indirect comparison based on evidence from uncontrolled clinical longitudinal studies and from direct comparisons based on RCT evidence are not the same . The distributions of the point estimates differed significantly for both comparison types ( Mann – Whitney U = 25 , nindirect = 26 ; ndirect = 8 ; p = 0.0013 , two-tailed ) . Conclusion The null-hypothesis was rejected . Trends and performance differences inferred from either comparison between HVGIC and amalgam restorations failure rates in permanent posterior teeth are not the same . It is recommended that clinical practice guidance regarding HVGICs should rest on direct comparisons via RCTs and not on naïve-indirect comparisons based on uncontrolled longitudinal studies in order to avoid inflation of effect estimates Pain during invasive treatment of dental caries is a common phenomenon , if no local analgesia has been used before cavity preparation . Atraumatic restorative technique ( ART ) is a suggested procedure which is at least less traumatic for the patient . Although the ART approach has been received well by both children and adults who belong to population groups hardly ever exposed to regular oral health care , it has not yet been proven that this particular procedure really causes less pain , compared to more conventional techniques with rotating instruments . In the present study , pain was reported in connection with tooth restoration in 19.3 percent of the cases , when the ART technique was used , which is significantly less than with a conventional restorative technique ( 35.7 percent ) . Finally the results show a clear relationship in the pain reports between the first and the following treatments in both ART and the conventional technique groups The atraumatic restorative treatment technique ( ART ) is based on removing infected tooth material using only h and instruments and filling the subsequently cleaned cavity with adhesive material such as glass ionomer . As its name suggests , the ART technique should be atraumatic during treatment , as well as for the tooth itself as for the patient . It was primarily developed for treating people living in underserved areas of the world where re sources and facilities such as electricity and trained manpower are limited . Many studies have evaluated the ART technique and the results have supported its application . However , a very limited number of studies have compared ART with more conventional techniques . For that reason , a study was conducted in Pakistan , to compare the ART technique with another more conventional treatment technique . The results of this study show that the preparations with h and instruments result ed in smaller sized cavities and therefore may be less traumatic to the tooth . It was also associated with less pain reactions compared to the more conventional technique . Although preparations with h and instruments required more time , this did not seem to affect the survival of restorations . The survival of glass ionomer cement restorations  made with h and instruments was comparable with single surface amalgam restorations made with a more conventional technique . Recurrent caries was not associated with any glass ionomer cement restorations made with h and instruments . The retention rate of glass ionomer sealants was low , however one dentist had a sealant retention rate of 81.5 percent that suggests that this procedure can be performed satisfactorily in conjunction with a glass ionomer cement restoration . Operator variances did seem to affect the restorations . Survival of glass ionomer restorations  made with both h and and rotary instruments varied for different operators . Similarly , the retention of fissure sealant also varied amongst operators . Operator differences also influenced the extent of tooth substance lost due to cavity preparation . The ART technique is a feasible approach towards the treatment of dental caries especially of one-surface lesions for underserved population
target: Conclusion The current evidence suggests lack of support for the hypothesis that high-viscosity glass-ionomer cements are inferior to silver amalgam as restorative material s for permanent posterior teeth .
background: Background To develop a synthesis within a Bayesian probability framework of previously established evidence , in order to derive an overall conclusion about the hypothesis ( H1 ) : ‘ High-viscosity glass-ionomer cements ( HVGIC ) are inferior to silver amalgam as ( load bearing ) restorative material s for permanent posterior teeth ’ .