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Glass ionomer restorations are as successful as amalgam and are considered as permanent restorations.

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

Mickenautsch S1.
Author information:

1SYSTEM Initiative, Department of Community Dentistry, Faculty of Health Sciences, University of the Witwatersrand, 7 York Rd., Parktown/Johannesburg, 2193, South Africa. neem@global.co.za.
Abstract
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 materials for permanent posterior teeth’.

METHODS:
Following Bayesian method, the prior Odds that H1 is true (established from past uncontrolled clinical longitudinal and laboratory trials), the Likelihood Ratio incorporating new evidence (established from recent meta-epidemiological studies and systematic reviews of controlled clinical trials), as well as the posterior hypothesis Odds in view of the new evidence, were calculated.

RESULTS:
The prior Odds that HVGICs are clinically inferior to amalgam as restorative materials in posterior permanent teeth in relation to the hypothesis that this is not so was 1.12 to 1. The Likelihood Ratio based on new evidence in favor the hypothesis was zero and the subsequent posterior Odds 0 to 1. Therefore, based on the new evidence, the Odds that HVGICs are clinically inferior to amalgam as restorative materials in posterior permanent teeth degreased from 1.12 to zero.

CONCLUSION:
The current evidence suggests lack of support for the hypothesis that high-viscosity glass-ionomer cements are inferior to silver amalgam as restorative materials for permanent posterior teeth. Should future research to this topic uphold the current findings, a wider range of clinical benefits for both patient and care provider, beyond appropriate restoration longevity for placing HVGIC based restorations may apply.

PMCID: PMC4599034 Free PMC Article
PMID: 26449638 [PubMed – in process]
1. BMC Oral Health. 2015 Oct 8;15(1):118. doi: 10.1186/s12903-015-0108-5.

Influence of additional heating on the microhardness of glass ionomer cements

 Influence of additional heating on the microhardness of glass ionomer cements

Abstract

Purpose: The objectives of this study were to verify for various GIC products, whether the application of external heat on the initial curing material, produces an increase in microhardness, and to determine whether this hardness varies, dependent of the depths in the GIC samples. Moreover, the efficacy was examined of various polymerization units on this additional hardening.

Methods: The GICs samples were thermo-cured for 60s with three polymerization units. The Vickers micro-hardness was measured at three different depths: 2, 3 and 4 mm. The statistical analysis was performed by one-way ANOVA, Newman-Keuls test and linear regression analysis. Statistical significance was set to p<0.05.

Results: Analysis of variance and Newman-Keuls test showed statistically significant difference among tested groups for all three GICs. The results of linear regression analysis showed statistically significant correlation between the hardness of the material and temperature for 2 mm (R=0.78; p=0.0028) and 3 mm depth (R=0.59; p=0.045).

Clinical Significance: The results of this study indicate that thermal-curing of GIC with different polymerization units for 60s during setting reaction increases the microhardness of the GICs at all depths, and consequently resistance to mastication forces which is extremely important for clinical success of restorations.

 

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Glass ionomers also suitable for permanent posterior restorations!

Glass ionomers also suitable for permanent posterior restorations

 

Glass Ionomer restorations are often not used posterior because the occlusal forces are too high for GI in vitro. However, a clinical (in vivo!) study showed that glass Ionomers just performing as well as amalgam, writes ZWP online.

 

Restorations
The researchers compared 10,000 dental restorations from previous studies. They conclude that glass ionomers is also suitable for choose.
To six years after the restoration glass ionomers performs as well as composite or amalgam.

 

Afbeelding

online source ZWP University of the Witwatersrand

 

Jan 2014