GLASS-IONOMER DENTAL RESTORATIVE .1. A STRUCTURAL STUDY

A structural study of glass-ionomer cement (GIC) dental restoratives h as been completed. Transmission electron microscopy, selected area ele ctron diffraction, and X-ray diffraction studies indicate domain-like microstructure in a new experimental material, whereas a featureless a morphous gel-like microstructure exists in the conventional GIC. Nucle ar magnetic resonance studies were also conducted. The new experimenta l GIC contains domains of (i) bonelike material (apatite), (ii) mesopo rous material and (iii) other framework structures (aluminium phosphat e in the high cristobalite structure), with its setting chemistry a re structuring of the aluminosilicate glass around the template of poly(a crylic acid). Conventional glass-ionomer cement may set by a similar b ut slower process. Leaching properties of glass-ionomer cements are al so explained.