Adhesion of glass-ionomer cement in the clinical environment.

This paper discusses the literature concerning the development of an ion-enriched layer between the glass-ionomer cement and tooth structure. Two restorations that had been in the oral cavity for considerable periods of time were used to confirm the existence of this layer. It is suggested that development of the layer is dependent on careful adherence to the recommendations for clinical placement, and recognition of the need to clean the surface of the cavity and to maintain the water balance of the cement. Having developed the ion-exchange layer, failure will be cohesive in the cement itself. Thus the strength of the union is dependent on the tensile strength of the cement.