“…However, simple phosphate glasses are hygroscopic and have poor chemical durabilities. The addition of trivalent ions (Al 3+ , B 3+ , Bi 3+ , …) into the phosphate network improves physical properties and enhances chemical stability by forming cross-linking M 3+ \O\P bonds [10][11][12][13][14][15][16]. Recent studies have shown that addition of B 2 O 3 not only increases the mechanical properties but also allows a more rapid conversion to HA over the glass surface [3,[17][18][19][20][21].…”