Calcium-Strontium-based glasses

Calcium-Strontium-Based Glasses/Electrolytes Interfaces... 

There is bound to be one problem with resin glass polyalkenoate cement. Because the matrix is a mixture of hydrogel salt and polymer, lightscattering is bound to be greater than in the conventional material. Moreover, the zinc oxide-containing glass of class II materials is bound to be opaque. This makes it difficult to formulate a translucent material and is the reason why their use is restricted to that of a liner or base. However, the class II material cited will be radio-opaque because it uses strontium and zinc, rather than calcium, in the glass. 

The only ones that have so far found practical application in glass-ionomers for dentistry are alumino-silicate glasses, with fluoride and phosphate additions. These are typically calcium based, with some extra sodium, though successful commercial materials exist in which calcium has been wholly or partly replaced by strontium. 

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