Some physical and biological properties of glass ionomer cement.

It has become apparent through both clinical use and laboratory experiments that the glass ionomer cements have several highly desirable properties. They show a continuing fluoride release and the ability to take up further fluoride under favourable conditions. The presence of fluoride also helps to inhibit plaque formation. The adhesion between tooth structure and cement also results in almost complete prevention of the bacterial micro-leakage. Also, the cement itself is so highly bio-compatible that it is now being used as a bone substitute and it has become apparent that there is no need to place a sub-lining under a glass ionomer restoration. Recent research is leading to the development of self curing cements with enhanced physical properties so that, in the presence of the above advantages, their use in clinical dentistry is rapidly expanding. Glass ionomer cements are of great value for any restoration which is not under undue occlusal stress and they work well also as a long term temporary restoration in the presence of a high caries rate, where zinc oxide and eugenol used to be the material of choice.