DO GLASS IONOMER CEMENTS MATURE APPRECIABLY? A CRITICAL REVIEW

Authors: Shahid MAHMOOD, Saroash SHAHID, Richard BILLINGTON

Abstract:

Introduction: The earliest glass ionomer cement (GIC) had low strength when tested after 24 hours. However, after long periods, strength increased. This was initially thought to be a property of all GICs, but some later materials either did not increase or got weaker. Objectives: This review aims at determining whether changes in the chemical composition of the glass component of GICs do result in different strength changes or whether other formulation changes are also responsible. In addition, it aims at evaluating changes in other non-mechanical properties, such as abrasion and erosion. Materials and methods: Search engines were used to find relevant references included in Ovid SP, Pubmed and Index Copernicus.Results and discussion:  In experimental GICs strength, changes have an inverse correlation with initial (24 hours) strength. For commercial GICs, no such relationship is found. High phosphorus contents result in large increases in strength from initial low strength values. Other properties also show maturation changes. In particular, both resistance to abrasion and erosion increase in the relatively few GICs tested, including some which do not show strength increases. Conclusions:  GICs have the potential to improve their properties when matured for periods longer than 24 hours, however this property is dependent on glass composition.

Keywords:
  • compressive strength
  • glass ionomers
  • maturation