抄録
A new type of glass-ceramic for novel dental fillers, which require excellent chemical durability, was investigated. Three types of glass-ceramics were prepared using compositions of 40CaO-xCaF2-(5-x)Na2O-25TiO2-3OP2O5 (in mol%, x=0, 2.5, 5). With increasing CaF2amount, both glass transition temperature and crystallization temperature increased. The glass-ceramics were prepared by a conventional two-step heating method. In 40CaO-5Na2O-25TiO2-30P2O5 glass-ceramic, Nasicon-type RTi2(PO4)3 (R=Na, 1/2Ca) and P-tricalcium phosphate (β-TCP) crystals were precipitated in the glass-ceramic. By incorporation of fluorine to the glass, the formation of β-TCP was controlled and fluoroapatite was found to be formed preferentially. In 40CaO-5CaF2-25TiO2-30P2O5 glass-ceramic,dissolution by acid-treatment was strictly controlled. In the present work, a new type of apatite-containing phosphate glass-ceramic without silica, based on the above-mentioned glass composition, could be newly prepared.
