Production and characterization of a glass-ceramic biomaterial and in vitro and in vivo evaluation of its biological effects

Objectives: Glass-ceramics are biomaterials that are usu¬ally produced by the sol-gel technique and can be used as a substitute for bone. One important feature of glass- ceramics is osteointegration with bone tissue. This study was designed to produce a glass-ceramic and evaluate its structure and in vitro and in vivo biological effects. Methods: With the sol-gel method, a glass-ceramic was synthesized in the form of 30SiO2-17MgO-53Ca3(PO4)2 us¬ing tetraethylorthosilicate, dibutyl phosphate, magnesium, and calcium nitrate. Glass-ceramic jel samples were sin¬tered at temperatures up to 1100 °C and their microstruc- ture and phases were examined by the X-Ray diffraction (XRD) technique and scanning electron microscopy. For in vitro tests, the samples were immersed in a simulative body fluid (SBF) for 10, 30, and 40 days to be analyzed by XRD. For in vivo tests, the samples were placed in tibial metaphyses of Sprague-Dawley rats for 4, 6, and 8 weeks for histological evaluation of osteointegration. Results: As the temperature increased, growth of crystal phases was noted. While XRD analysis showed no change in samples that were kept in SBF for 10 days, hydroxyapa- tite crystals were seen after 30 and 40 days of SBF treat¬ment in the second and third degree of crystal phases. In vivo test results showed that the glass-ceramic possessed a high tendency to replace osteoid bone tissue, with full osteointegration at eight weeks. Conclusion: The glass-ceramic produced has a high surface reactivity and can be used as a bone substitute material.