Direct Contra Naïve-Indirect Comparison of Clinical Failure Rates between High-Viscosity GIC and Conventional Amalgam Restorations: An Empirical Study Is high-viscosity glass-ionomer-cement a successor to amalgam for treating primary molars? Long-term clinical evaluation of fracture and pulp injury following glass-ionomer cement or composite resin applied as a base filling in teeth restored with amalgam. Survival of ART and Amalgam Restorations in Permanent Teeth of Children after 6.3 Years
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 OBJECTIVES To assess and compare the cumulative survival rate of amalgam and atraumatic restorative treatment ( ART ) restorations in primary molars over 3 years . METHODS 280 children aged 6 - 7 years old were enrolled in a cluster r and omized controlled clinical trial using a parallel group design covering two treatment groups : conventional restorative treatment with amalgam ( CRT ) and atraumatic restorative treatment ( ART ) using a high-viscosity glass-ionomer ( HVGIC ) Ketac Molar Easymix . Three pedodontists placed 750 restorations ( 364 amalgam and 386 ART in 126 and 154 children , respectively ) which were evaluated at 0.5 , 1 , 2 and 3 years . The proportional hazard rate regression model with frailty correction , ANOVA and Wald tests , and the Jackknife procedure were applied in analysing the data . RESULTS The cumulative survival rates over 3 years for all , single- and multiple-surface CRT/amalgam restorations ( 72.6 % , 93.4 % , 64.7 % , respectively ) were no different from those of comparable ART/HVGIC restorations ( 66.8 % ; 90.1 % and 56.4 % , respectively ) ( p=0.10 ) . Single-surface restorations had higher survival rates than multiple-surface restorations for the both treatment procedures ( p<0.0001 ) . A higher proportion of restorations failed because of mechanical reasons ( 94.8 % ) than of secondary caries ( 5.2 % ) . No difference in reasons for restoration failures between all types of amalgam and ART/HVGIC restorations were observed ( p=0.24 ) . SIGNIFICANCE The high-viscosity glass-ionomer used in this study in conjunction with the ART is a viable option for restoring carious dentin lesions in single surfaces in vital primary molars The aim of this research was to analyse the long-term clinical behaviour of two dental material s applied as filling under  silver amalgam restorations  : glass-ionomer cement ( GIC ) and composite resin with adhesive system ( CR ) . In this study , 117 posterior teeth ( 29 premolars and 88 molars ) were selected with carious lesions which result ed in great loss of dentin and cusps with unsupported enamel . After caries removal , cavities were prepared and totally filled with GIC or with CR . In a following visit , new cavities were prepared , leaving the employed filling material as a base and support for the enamel , which were then restored with silver amalgam . Restorations were evaluated periodically after 6 months and up to 5 years . Both fracture and pulpal involvement rates were low . Although differences could be observed in the behaviour of the material s , statistical survival estimation showed that the performances of GIC and CR as filling material were similar . There was a significant association both between kind of tooth ( molar or premolar ) and long-term survival of the restorations ; and between degree of unsupported enamel and the same long-term survival . Our results confirmed that the technique in which GIC or CR are used as filling under  silver amalgam restorations is clinical ly acceptable The null hypothesis tested was that there is no difference in the survival percentages of all restorations placed through the Atraumatic Restorative Treatment ( ART ) approach , with high-viscosity glass ionomer , and those produced through the traditional approach , with amalgam ( TA ) , in the permanent dentitions of children after 6.3 years . Using a parallel group design , we r and omly assigned a total of 370 children , aged 6 to 9 years , to the ART group and 311 children , also aged 6 to 9 years , to the TA group . Eight dentists placed a total of 1117 single- and multiple-surface restorations . The cumulative survival percentages  for ART glass-ionomer restorations were statistically significantly higher than those of amalgam restorations at all time intervals except the first ( p ≤ 0.044 ) . After 6.3 years , the cumulative survival percentages of ART and amalgam restorations were 66.1 % ( SE = 3.1 % ) and 57.0 % ( SE = 3.3 % ) , respectively . We concluded that the restorations produced with the ART approach , with high-viscosity glass ionomer , survived longer than those produced with the traditional approach , with amalgam , in the permanent teeth of young children
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 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 ’ .