Low Temperature Sintering of Innovative Bioactive Glasses

Two innovative glass compositions based on the commonly used 45S5 Bioglass (R) were developed by increasing the calcium quantity and replacing the sodium oxide with a specific content of potassium oxide. The new glasses, named BG_Ca/K and BG_Ca/Mix, can be prepared using a conventional melting process and show a very low tendency to crystallize. Thanks to this peculiarity, BG_Ca/K and BG_Ca/Mix powders can be sintered at a relatively low temperature (800 degrees C) to obtain samples of high compactness and bioactivity, since their amorphous nature is preserved. Consequently, the proposed glasses are perfect for making specific products such as scaffolds or hydroxyapatite-based composites. Furthermore, the relatively low alkali amount in the new compositions gives rise to a slow ion leaching in simulated body fluid, thus avoiding abrupt changes in pH that can damage osteoblasts or negatively affect their behavior.