Biocompatibility of a new bio-glass composition was evaluated with the addition of fluorides, such as CaF2 and MgF2, for the substitution of Na2O in the conventional bio-glass composition (SiO2-CaO-Na2O-P2O5). Also, the physical properties of Na2OCaO- SiO2-P2O5 glass ceramics were investigated. When B2O3 (4 mol%) was added as a Na2O substitution, the thermal expansion coefficient was decreased in sintered samples (650-950 oC). Compared to the low flexural strength (57 ± 3MPa) and Vickers hardness (4.6 GPa) of sintered bio-glass ceramics without fluoride and B2O3 additions, new bio-glass ceramics substituted with 10 mol% MgF2 for Na2O showed more higher mechanical properties (flexural strength: 141 ± 5 MPa, Vickers hardness: 5.6 GPa). The thermal expansion coefficient of bio-glass ceramics due to the ion substitutions (Ca2+, Mg2+ and B3+) was decreased from 16 × 10-6/ oC to 9.4-10 × 10-6/ oC (~400 oC)

Keywords: Bio-glass Ceramics, CaF2, MgF2, Physical Properties, Biocompatibility