[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 usually 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 using tetraethylorthosilicate, dibutyl phosphate, magnesium, and calcium nitrate. Glass-ceramic jel samples were sintered at temperatures up to 1100 degrees C and their microstructure 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, hydroxyapatite crystals were seen after 30 and 40 days of SBF treatment 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.