The purpose of this study was the reaching test of restorative glass according to composition. Mixtures of SrF₂, CaF₂and SiO₂were fused in platinum crucible. The glasses were ground and fraction which passed through a 400 mesh (38㎛) sieve were collected. The powder specimens were analyzed by a DTA and XRD. Then powder specimen were inserted to D. I. water with various of dissolution time and composition at 37℃. Fluoride ion, cation release, solubility, and pH change were estimated.
It was clear that the glasses were formed except S0.65. In S0.40, Tg, Ts, and Tc were 630, 672, and 813℃ respectively.
In initial 0.5 hrs., amounts of released fluoride ion and cation were about 90% of total released amounts and released rate was decreased with dissolution time. Amount of released fluoride ion and cation were increased with decreasing SiO₂ in glass filler. And released rate was decreased rapidly by adding CaF₂. This was caused by structural variation in glass filler. Solubility was similar tendency with ion released.
The pH of D.I. water was 4.5. But in intial 0.5 hrs., pH was 8.2∼9.8., and decreased according to dissolution time. This is caused by ionic changing with cation and H* ion.