Optimization of Additional Composition Variations ZnO Nanoparticles on The Characteristics of Porous Hydroxypatite as Bone Filler

Research on the synthesis and characterization of porous hydroxyapatite with the addition of ZnO nanoparticles has been carried out through a combination of foam immersion and injection methods. This research was conducted to optimize the previous research by increasing the variation of ZnO composition and adding the injection method to the research process. The materials used in this research include hydroxyapatite nanoparticles, ZnO nanoparticles, Aquades, PVA and polyurethane foam. Manufacturing is done by immersing polyurethane foam into a slurry. Slurry is a mixture of PVA and hydroxyapatite solutions with variations in the addition of ZnO nanoparticles (8 wt%, 10 wt%, 12 wt%, and 14 wt%). Then inject the remaining slurry into the foam. After that the sample was dried and heated at a temperature of 650ºC to remove foam and PVA, then the sample was sintered at a temperature of 1200ºC for 3 hours. Based on SEM analysis, porosity test, and compressive strength test, the best results were shown by sample IV because it had a pore diameter of 142.9 – 371.4 m with a porosity of 69.983%, a compressive strength value of 1.8653 MPa and non-toxic. The best results have not met the standard for bone filler application. In further research, improvements need to be made by using other additives such as ZrO2, so that it can improve the mechanical properties of porous hydroxyapatite to meet standard bone filler applications.

Case Report: Osteomesh Cranioplasty in a 20-Year-Old Trauma Patient

In this study, we present a case of a 20-year-old male who suffered from severe traumatic brain injury with intracerebral hemorrhage, thus requiring decompressive craniectomy. Five months after, the patient underwent cranioplasty with the use of Osteomesh, a scaffold bone filler in reconstructing the post-operative cranial defect.

In Vivo Analyses of Osteogenic Activity and Bone Regeneration Capacity of Demineralized Freeze-Dried Bovine Bone Xenograft: A Potential Candidate for Alveolar Bone Fillers

Background. Deproteinized bovine bone mineral (DBBM) particle is the commonly used bone graft substitute in implant surgery which is mainly osteoconductive and has very slow degradation. Demineralized freeze-dried bovine bone xenograft (DFDBBX) particle is being developed as a novel xenogeneic bone filler. Objectives. The study aimed to analyze osteogenic activity and bone-forming capacity of DFDBBX particles compared to DBBM particles in alveolar bone defects in rabbit mandibles models. Material and Methods. This study investigated bone defects whether filled with DBBM particles or DFDBBX particles or left unfilled in 30 rabbit mandibles. Specimens were processed for histology, immunohistochemistry, and micro-CT scanning. Statistical difference was set at a p value < 0.05. Results. The quantitative assessment showed a significantly lower number of osteoclasts and a higher number of osteoblasts in the DFDBBX group compared to the DBBM group in 2 and 4 weeks ( p < 0.05 ). Immunostaining analyses showed significantly higher expression of RUNX2, collagen type I, alkaline phosphatase, and osteocalcin in the DFDBBX group compared to the DBBM group in 2 and 4 weeks. Bone healing score in the DFDBBX group was comparable to the DBBM group. Micro-CT presented no significant difference in the volume percentage of the mineralized tissue in the DBBM and DFDBBX groups in spite of the different healing patterns in both groups. Conclusion. DFDBBX particles induced higher osteoblastic activities than DBBM particles at the early stage of healing. Meanwhile, the capacity of bone formation in DFDBBX particles was comparable with DBBM particles at the later stage of healing. Considering the limitation of this study, the results presented DFDBBX particles as potential bone filler candidates.

Evaluation of a bone filler scaffold for local antibiotic delivery to prevent Staphylococcus aureus infection in a contaminated bone defect

We previously reported the development of an osteogenic bone filler scaffold consisting of degradable polyurethane, hydroxyapatite, and decellularized bovine bone particles. The current study was aimed at evaluating the use of this scaffold as a means of local antibiotic delivery to prevent infection in a bone defect contaminated with Staphylococcus aureus. We evaluated two scaffold formulations with the same component ratios but differing overall porosity and surface area. Studies with vancomycin, daptomycin, and gentamicin confirmed that antibiotic uptake was concentration dependent and that increased porosity correlated with increased uptake and prolonged antibiotic release. We also demonstrate that vancomycin can be passively loaded into either formulation in sufficient concentration to prevent infection in a rabbit model of a contaminated segmental bone defect. Moreover, even in those few cases in which complete eradication was not achieved, the number of viable bacteria in the bone was significantly reduced by treatment and there was no radiographic evidence of osteomyelitis. Radiographs and microcomputed tomography (µCT) analysis from the in vivo studies also suggested that the addition of vancomycin did not have any significant effect on the scaffold itself. These results demonstrate the potential utility of our bone regeneration scaffold for local antibiotic delivery to prevent infection in contaminated bone defects.

Evaluation of a polymeric composite bone filler scaffold for local antibiotic delivery to prevent Staphylococcus aureus infection in a contaminated bone defect

We previously reported the development of an osteogenic bone filler scaffold consisting of degradable polyurethane (dPU), nano-sized hydroxyapatite (nHA), and decellularized bovine bone particles (DBP). In this report we describe the results of studies aimed at evaluating the use of this scaffold as a means of local antibiotic delivery for the prevention of infection in a segmental bone defect contaminated with Staphylococcus aureus. We evaluated two different scaffold formulations that contained the same components in the same ratios but differed from each other with respect to overall porosity and therefore surface area. Studies done with vancomycin, daptomycin, and gentamicin confirmed that antibiotic uptake was concentration dependent and that increased porosity was correlated with increased uptake and prolonged release of all three antibiotics. Vancomycin could be passively loaded into either scaffold formulation in an amount sufficient to prevent infection, as evidenced by the complete eradication of viable bacteria from the surgical site of most animals in a rabbit model of a contaminated mid-radial segmental bone defect. Even in those few cases in which complete eradication was not achieved, the number of viable bacteria present in the bone was significantly reduced comparison to untreated controls. There was also no radiographic evidence of osteomyelitis in any rabbit treated with vancomycin-loaded scaffold. Microcomputed tomography (μCT) of bone defects up to 84 days of exposure to scaffolds with and without vancomycin also demonstrated that the addition of vancomycin even in the highest concentration did not significantly diminish the osteogenic properties of either scaffold formulation. Together, these results demonstrate the potential utility of our bone regeneration scaffold for local antibiotic delivery.