Dental compositions incorporating glass ionomers

Claim 1

A buffered glass ionomer cement for dental use, including in combination, a mixture of (A) (1) a fine particle, 5-10 microns, powder consisting essentially by weight ______________________________________ silica 20-30% boron oxide 1-10% aluminum oxide 10-20% aluminum fluoride 1-10% calcium fluoride 30-40% phosphorus pentoxide 1-5% ammonium fluoride 1-10% ______________________________________ said powder being obtained from glass resulting from the fusing together of said silica, boron oxide, aluminum oxide, aluminum fluoride, calcium fluoride, phosphorus pentoxide, and ammonium fluoride, then fritting and ball milling to the fine particle size, 5-10 micron, powder, and (2) five to twenty percent of the weight of (1) of powdered zinc oxide and zero to ten percent of powdered titanium dioxide, added to said powder (1) and mixed therewith only after said fritting and ball milling, and (B) a liquid component comprising, by weight (1) 100-80% by weight of polyacrylic acid of low molecular weight, 40% solution in water and (2) 0-20% of d-tartaric acid, said powder component (A) and said liquid component (B) being mixed together in a ratio of from 1:1 to 5:3 by weight.