Do Laboratory Results Concerning High-Viscosity Glass-Ionomers versus Amalgam for Tooth Restorations Indicate Similar Effect Direction and Magnitude than that of Controlled Clinical Trials? - A Meta-Epidemiological Study

Abstract

BackgroundA large percentage of evidence concerning dental interventions is based on laboratory research. The apparent wealth of laboratory evidence is sometimes used as basis for clinical inference and recommendations for daily dental practice. In this study two null-hypotheses are tested: whether trial results from laboratory and controlled clinical trials concerning the comparison of high-viscosity glass-ionomer cements (HVGIC) to amalgam for restorations placed in permanent posterior teeth have: (i) similar effect direction and (ii) similar effect magnitude.Methods7 electronic databases were searched, as well as reference lists. Odds ratios (OR) and Standardised Mean Differences (SMD) with 95% Confidence intervals were computed for extracted dichotomous and continuous data, respectively. Pooled effect estimates for laboratory and clinical data were computed to test for effect direction. Odds ratios were converted into SMDs. SMDs from laboratory and clinical data were statistically compared to test for differences in effect magnitude. The analysed results were further investigated within the context of potential influencing or confounding factors using a Directed acyclic graph.ResultsOf the accepted eight laboratory and nine clinical trials, 13 and 21 datasets could be extracted, respectively. The pooled results of the laboratory datasets were highly statistically significant in favor of amalgam. No statistically significant differences, between HVGICs and amalgam, were identified for clinical data. For effect magnitude, statistically significant differences between clinical and laboratory trial results were found. Both null-hypotheses were rejected.ConclusionLaboratory results concerning high-viscosity glass-ionomers versus amalgam for tooth restorations do not indicate similar effect direction and magnitude than that of controlled clinical trials.

Shear bond strength of a novel light cured calcium silicate based-cement to resin composite using different adhesive systems

“…In the current study, SBS of the conventional GIC to resin composite was lower than TheraCal LC but significantly higher than MTA. Several factors such as the flow (viscosity) of GIC may be related to its bond strength to resin composite since it affects its adaptability to the surface; low adaptability may lead to partial defects on the restoration margin and small voids which may affect bond strength values to composite 37) . In addition, the lack of chemical bond between conventional GICs and composite in addition to the low cohesive strength of GICs lead to bond strengths that are likely to be lower 38) .…”

Clinical Performance of a Glass Hybrid Restorative in Extended Size Class 2 Preparations

“…Laboratuvar çalışmaları da yüksek viskoziteli Cİ'lerin rezin kompozitler ile rekabet edebilecek özelliklerde olduğunu göstermiştir. 21,26,27 Literatürde, amalgam veya rezin kompozitler üzerine yapılan çalışmalar çok fazla olmasına rağ-men, bugüne kadar Cİ esaslı restoratif sistemlerin klinik başarısı ile ilgili sadece birkaç çalışma bildirilmiştir. [28][29][30] Bu çalışmalar da çoğunlukla 1. sınıf preparasyonlarda yapılmıştır.…”

Are high-viscosity glass-ionomer cements inferior to silver amalgam as restorative materials for permanent posterior teeth? A Bayesian analysis

“…This systematic review was further updated [ 7 ] and the detailed results, including additional results from Chinese trials, published by the authors [ 8 , 9 ]. All published reports of this systematic review indicated no differences between HVGIC and amalgam, beyond the play of chance (p > 0.05) in the permanent dentition after four and six years for single and multiple surface tooth restorations, respectively, and no differences after three years for single and multiple surface restorations in primary teeth [ 6 , 7 , 10 ]. The results from Chinese trials were confirmatory of these findings [ 8 ].…”

“…A meta-epidemiological study was conducted in order to test the null-hypotheses whether the results from laboratory trials concerning HVGICs versus amalgam indicate similar effect direction and magnitude as results from clinical controlled trials concerning HVGICs versus amalgam restorations placed in permanent posterior teeth [ 10 ]. The results of this study showed that the effect direction and magnitude are not similar and that, similar to the investigation concerning the naïve-indirect-indirect comparison method based on evidence from clinical uncontrolled longitudinal studies [ 1 ], the null-hypotheses had to be rejected.…”

“…The results of this study showed that the effect direction and magnitude are not similar and that, similar to the investigation concerning the naïve-indirect-indirect comparison method based on evidence from clinical uncontrolled longitudinal studies [ 1 ], the null-hypotheses had to be rejected. In addition, this study raised reasons for doubt regarding the general suitability of laboratory trials for clinical inference [ 10 ].…”