Article

An In Vitro Biocompatibility Study of Conventional and Resin-modified Glass Ionomer Cements

The journal of adhesive dentistry (Impact Factor: 1.31). 04/2013; 15(6). DOI: 10.3290/j.jad.a29588
Source: PubMed

ABSTRACT

Purpose:
To evaluate the biocompatibility of a glass-ionomer (GIC) and a resin-modified glass-ionomer cement (RM-GIC), cell viability was examined in a model of human gingival fibroblasts using morphological, biochemical, and ionic patterns by means of phase contrast microscopy, lactate dehydrogenase (LDH) release, and quantitative x-ray microanalysis (EPXMA).

Materials and methods:
The GIC Ketac-Molar Easymix (3M ESPE) and the RM-GIC Vitrebond (3M ESPE) were compared in human gingival fibroblasts exposed to the cements for 72 h. As controls, fibroblasts cultured with DMEM culture medium (negative control) and with 1% triton × (positive control) were used.

Results:
Light microscopic findings showed greater morphological alterations in cells exposed to RM-GIC than to GIC. The relative percentage of LDH released from the cells to the supernatant was significantly higher in RMGIC cultures than in the control. Quantitative x-ray microanalysis showed that cultures exposed to RM-GIC were characterized by an increase in intracellular Na and a decrease in intracellular Cl and K. These changes in ion composition were significant compared to control and GIC cultures.

Conclusion:
The three indicators of cellular biocompatibility after 72 h of exposure showed that RM-GIC led to more marked alterations than GIC in human gingival fibroblasts.

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