The split network analysis for exploring composition–structure correlations in multi-component glasses: I. Rationalizing bioactivity-composition trends of bioglasses

We present a strategy, referred to as “split network” analysis, for assessing the average network polymerization (rF) and mean number of bridging oxygen (BO) atoms (N̅BOF) for each individual network former F in multi-component oxide-based glasses, primarily targeting those involving Al, B, P and Si. This requires a priori knowledge about the parameters {rF, N̅BOF} of all network builders, but one, whose values are deduced by the split network procedure. We illustrate split-network concepts for establishing composition/structure/bioactivity correlations in Na–Ca–Si–P–O glasses. The cooperating influences on the bioactivity from the average polymerization degree of the silicate network and the amounts of orthophosphate and sodium ions are discussed.