In Vivo Biocompatibility of Zinc-Doped Magnesium Silicate Bio-Ceramics

Magnesium-based bioceramics have emerged as a new class of biodegradable bone replacement material due to their higher degradation and good cytocompatibility. In the current research, we have prepared pure and zinc-doped magnesium silicate (MgS) bioceramics by solid state method and evaluated the in vitro degradability and in vivo biocompatibility. In vitro degradation of the MgS bioceramics was assessed in simulated body fluid (SBF) which showed enhanced degradability for 0.5 wt % Zn doped MgS samples. The in vivo biocompatibility was evaluated by implanting the samples in rabbit femur critical size defect. All the MgS samples were well-integrated at the host tissue site as evident in 90 day radiographic images and micro computed tomography (μ-CT). Oxytetracycline labeling indicated that 0.5 wt % Zn doped MgS samples had better bone regeneration after 90 days of implantation as compared to pure and 0.25 wt % Zn-doped samples. Any systemic and organ toxicity was negated by normal vital organ (heart, kidney, and liver) histology at 90 days.