A composite graft material containing bone particles and collagen in osteoinduction in mouse

Abstract

Demineralized allogenic bone matrices (DABM) and demineralized freeze-dried bone allograft (DFDBA) have been successfully used as bone-graft materials in the treatment of acquired and congenital cranio-maxillofacial defects and in some orthopedic surgery. However, these bone-graft "powders" have many shortcomings. For example, placement of particulate graft material in a hemorrhaging site can result in inadequacies or inaccurate attachment as well as loss of the graft materials. To minimize the inadequacies of powderlike graft materials, xenogenic collagen isolated from human tendon, skin, or bone was added to the bone-graft particles to form a composite spongelike implant. This material is commercially available and consists of 60% collagen and 40% DFDBA (DynaGraft, GenSci Co., Irvine, CA). The goal of this study was to evaluate the characteristics of composite graft implants in the mineralization process in an animal model in comparison with DFDBA powder and pure collagen. Seventy-two Swiss Webster mice were divided into three groups: an experimental group implanted with DynaGraft, two comparison groups implanted with either DFDBA or collagen only. All the graft materials were surgically implanted and inserted into the left thigh muscle. Mice were humanely killed at 1, 2, 3, 4, 6, 8, and 12 weeks. Then the muscle tissues in the vicinity of the implants were excised and processed for histology. Paraffin sections were stained with hematoxylin and eosin (H&E), the Von Kossa method, and Masson's trichrome. Some selected specimens were processed for transmission electron microscopic observation. After 1 week of implantation, the DynaGraft group showed calcium deposition on the collagen material and on the periphery of the DFDBA particles. Increased calcification and bone-forming cells were observed at 4-6 weeks. After 8 weeks, the implant formed a calcified nodule and only heavily mineralized connective tissue was observed at the implanted site. The group implanted with DFDBA powder showed calcification around the particulates. The collagen-sponge control group revealed no calcification or bone formation during the period of implantation. The light microscopic findings were confirmed by electron microscopy. Quantitative radiographic density DynaGraft and DFDBA graft followed sequentially over a period 120 days. It was concluded that a higher rate of calcification and bone formation was produced in the composite graft implant compared to the DFDBA implant. The composite graft material (DynaGraft), which contains both collagen and DFDBA, proved to be more effective for bone formation than particle components alone.

Perivascular Stem Cells: A Prospectively Purified Mesenchymal Stem Cell Population for Bone Tissue Engineering

“…1E, 1F). In contrast, intramuscular implantation of absorbable collagen sponge alone is known to have no bone forming effects [29]. Collectively, these studies showed that hPSCs (like their individual pericyte and adventitial components) undergo osteogenic differentiation in vitro and in vivo and thus may be useful as a purified cell source for bone formation.…”

“…1). This carrier was chosen as a nonosteoinductive carrier, as intramuscular implantation of absorbable collagen sponge alone is known to have no bone forming effects [29]. Second, an ovine DBX Putty was used (100 μl; Musculoskeletal Transplant Foundation, Edison, NJ, http://www.mtf.org).…”

Production and characterization of ECM powder: implications for tissue engineering applications

“…Therefore, the means to produce ECM powder and expand the potential clinical applications of this material may be important for the field of tissue engineering. The concept of using ECM powder with bioinductive properties has been utilized extensively for the delivery of demineralized bone matrix in periodontal and orthopaedic applications [17][18][19]. A powdered form of ECM provides a great deal more flexibility in terms of delivery of the material to target sites.…”

Acceleration of Bone Regeneration byBMP‐2‐Loaded Collagenated Biphasic Calcium Phosphate in Rabbit Sinus

“…4,5 Moreover, the resorption rate of this biomaterial can be controlled by modifying the mixing ratios of HA and β-TCP without altering its osteoconductive properties, 6,7 and the collagen matrix should stabilize the bone particles and help with the adsorption of blood coagulum at the initial stage of healing. 8 A recent study found that CBCP composite blocks loaded with BMP-2 facilitate 3D bone regeneration in a vertical augmentation model, yielding bone with a mature appearance. 9 In terms of the release kinetics of BMP-2, ACS exhibited an initial burst release pattern of BMP-2, whereas allografts and ceramics inefficiently released BMP-2.…”