A series of commercially available Glass-Ionomer Cements (GIC) added with three differently-shaped micrometric metallic fillers, the metallic fraction of commercially available dental amalgams, has been characterized from a mechanical, morphological and calorimetric point of view and with respect to the corrosion resistance in fluids simulating the oral cavity environment. Glass-Ionomer Cements have been proposed, in conservative dentistry, as substitutes of composite resins which, even though largely used over last decade, show inadequate chemical-physical properties and possible toxic effects on the odontoblast cells. However, the performances of trade GIC are not yet optimal for restorative technique in dentistry and need some improvements: to address this challenge the addition of metallic fillers could be a possible answer. The Glass-Ionomer Cements added with the employed micrometric metallic fillers show a general amelioration of their functional properties. On modified GICs, enhanced mechanical properties are observed with regard to non-modified GIC, in particular a noteworthy increase of the elastic modulus (up to sixfold for GIC Fuji II added with Valiant metallic filler) and of the stress at break (up to fourfold for GIC Fuji II added with New Gen metallic filler), thus approaching the dentine mechanical properties. Micrographic observations show a high compact structure of the added GICs, thus reflecting a reduction of shrinkage. Calorimetric and dilatometric analyses further confirm the suitability for applications in preservative dentistry. Finally, with respect to the corrosion resistance, the effect of the introduction of the metallic filler is beneficial in samples with low porosity.
Effect of micrometer-scale metallic fillers on the mechanical and corrosion resistance properties of alternative materials for conservative dentistry
L Ambrosio
2006
Abstract
A series of commercially available Glass-Ionomer Cements (GIC) added with three differently-shaped micrometric metallic fillers, the metallic fraction of commercially available dental amalgams, has been characterized from a mechanical, morphological and calorimetric point of view and with respect to the corrosion resistance in fluids simulating the oral cavity environment. Glass-Ionomer Cements have been proposed, in conservative dentistry, as substitutes of composite resins which, even though largely used over last decade, show inadequate chemical-physical properties and possible toxic effects on the odontoblast cells. However, the performances of trade GIC are not yet optimal for restorative technique in dentistry and need some improvements: to address this challenge the addition of metallic fillers could be a possible answer. The Glass-Ionomer Cements added with the employed micrometric metallic fillers show a general amelioration of their functional properties. On modified GICs, enhanced mechanical properties are observed with regard to non-modified GIC, in particular a noteworthy increase of the elastic modulus (up to sixfold for GIC Fuji II added with Valiant metallic filler) and of the stress at break (up to fourfold for GIC Fuji II added with New Gen metallic filler), thus approaching the dentine mechanical properties. Micrographic observations show a high compact structure of the added GICs, thus reflecting a reduction of shrinkage. Calorimetric and dilatometric analyses further confirm the suitability for applications in preservative dentistry. Finally, with respect to the corrosion resistance, the effect of the introduction of the metallic filler is beneficial in samples with low porosity.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
