Bioactivity and Biocompatibility of a Novel Wollastonite Glass-Ceramic Biomaterial

Using wet chemistry, a novel wollastonite glass-ceramic (WGC) was previously synthesized for onepiece dental implant applications. It exhibited high strength, and excellent chemical durability and machinability. Objectives of the present study were to evaluate the bioactivity and biocompatibility of this WGC and to compare its properties to those of In-Ceram^® yttria partially stabilized zirconia (YZ). Bioactivity of WGC and YZ was assessed by soaking specimens in simulated body fluid (SBF). Scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffraction were used to monitor the formation of hydroxyapatite (HA) on the specimen surfaces. WGC induced the formation of bone-like carbonated HA when soaked in SBF; in contrast, YZ specimens did not exhibit bioactivity, even after being soaked in SBF for 4 weeks. In vitro biocompatibility was studied by seeding MC3T3-E1 preosteoblastic cells and calvarial osteoblasts on the specimens. Cell attachment, focal adhesion formation, cell proliferation, and alkaline phosphatase (ALP) activity were evaluated. Both WGC and YZ supported osteoblast attachment and proliferation. Cell spreading, focal adhesion formation and ALP activity were comparable on both materials indicating excellent biocompatibility of WGC. We conclude that WGC is a promising material for non-metallic dental implant applications due to its bioactivity and biocompatibility.