Intini G, Andreana S, Margarone J III, et al. Engineering a bioactive matrix by modifications of calcium sulfate
ABSTRACT The goal of this study was to define the conditions for the fabrication of a bioactive matrix that induces and supports cell proliferation and tissue regeneration. The proposed hypothesis was that a composite graft could be engineered by the absorption of platelet-rich plasma (PRP) onto calcium sulfate (CS). Evaluation of the biological activity of the engineered grafts was based on osteoblast proliferation studies and scanning electron microscopy (SEM) analyses. Graft samples were created in a standard size and shape so that the surface available for attachment and cell proliferation was always identical. Proliferation data were expressed as counts per minute per group and differences among groups were statistically analyzed by analysis of variance followed by the Scheffé test (alpha = 0.1). SEM analysis showed that the combination of CS and PRP presents a preserved crystalline structure well integrated by organic matrix. This combination showed the highest cell proliferation levels (p < 0.001). Further evaluations demonstrated that PRP is activated when combined with CS. When tested as a possible carrier for biologically active molecules such as platelet-derived growth factor (PDGF), CS showed increased cell proliferation (p < 0.001). SEM revealed adherent osteoblasts with broad flattened edges on CS-PRP. This study proposes CS as an efficient carrier for PRP or PDGF and supports the use of these combinations as bioactive matrices in clinical or laboratory applications.
- SourceAvailable from: Mark Swihart
[Show abstract] [Hide abstract]
- "It can also be used as a compatible component, in a composite mixture with autogenous bone or demineralized freeze-dried bone allograft (Bateman et al 2005, Bell 1964, Bier 1970, Sottosanti 1992, Seymour and Heasman 1995). In addition to being inexpensive, readily available and easily sterilized, CS has been shown to be biocompatible and biodegradable, demonstrating a salutary tissue healing response and rarely causing postoperative complications (Radentz and Collings 1965, Shaffer and App 1971, Alderman 1969, Intini et al 2002). Although CS is osteoconductive and not osteoinductive in itself, in the presence of bone and/or periosteum it appears to become osteogenic (Frame 1975). "
ABSTRACT: Nanoparticles of calcium sulfate (nCS) have potential advantages as a ceramic matrix, scaffold and/or vehicle for delivering growth factors for osseous regeneration in a variety of clinical situations. The objectives of this study were to synthesize and characterize nanoparticles of hemihydrate calcium sulfate (nCS) and to develop a nCS-based system for bone regeneration. A cryo-vacuum method was used to process dihydrate CS into dihydrate nCS, which was then subjected to oven drying to produce hemihydrate. The nCS was sterilized by glow discharge treatment for use as a synthetic graft material for the treatment of bone defects. Electron microscopy showed that the nCS powder consisted of aggregates of closely arranged acicular crystals, approximately 30-80 nm in width, 400-600 nm in length and approximately 80-100 nm in diameter, providing a surface area about ten times that of conventional CS. Thorough physico-chemical characterization confirmed the composition and phase of the material. Cell viability/metabolic activity assays and alkaline phosphate assays confirmed the safety and biocompatibility of nCS. Release kinetics for adsorbed platelet-derived growth factor and bone morphogenetic protein-2 (BMP-2) suggests that nCS may serve as an appropriate vehicle for slow release delivery of these agents. The studies presented here give evidence of the advantages of nCS as a scaffold to support osteoblastic cell activity.Biomedical Materials 08/2011; 6(5):055007. DOI:10.1088/1748-6041/6/5/055007 · 3.70 Impact Factor
[Show abstract] [Hide abstract]
- "By mixing CS with PRP a malleable paste was obtained and applied at the surgical sites (Fig. 1, step 6). After 30 minutes CS-Platelet crystallized becoming a solid and homogeneous compound . According to each experiment or clinical case, the required amount of CS-Platelet was prepared by mixing CS with PRP in the ratio previously mentioned. "
ABSTRACT: With the present study we introduce a novel and simple biomaterial able to induce regeneration of bone. We theorized that nourishing a bone defect with calcium and with a large amount of activated platelets may initiate a series of biological processes that culminate in bone regeneration. Thus, we engineered CS-Platelet, a biomaterial based on the combination of Calcium Sulfate and Platelet-Rich Plasma in which Calcium Sulfate also acts as an activator of the platelets, therefore avoiding the need to activate the platelets with an agonist. First, we tested CS-Platelet in heterotopic (muscle) and orthotopic (bone) bone regeneration bioassays. We then utilized CS-Platelet in a variety of dental and craniofacial clinical cases, where regeneration of bone was needed. The heterotopic bioassay showed formation of bone within the muscular tissue at the site of the implantation of CS-Platelet. Results of a quantitative orthotopic bioassay based on the rat calvaria critical size defect showed that only CS-Platelet and recombinant human BMP2 were able to induce a significant regeneration of bone. A non-human primate orthotopic bioassay also showed that CS-Platelet is completely resorbable. In all human clinical cases where CS-Platelet was used, a complete bone repair was achieved. This study showed that CS-Platelet is a novel biomaterial able to induce formation of bone in heterotopic and orthotopic sites, in orthotopic critical size bone defects, and in various clinical situations. The discovery of CS-Platelet may represent a cost-effective breakthrough in bone regenerative therapy and an alternative or an adjuvant to the current treatments.Journal of Translational Medicine 02/2007; 5(1):13. DOI:10.1186/1479-5876-5-13 · 3.93 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Maxillary sinus lift is a surgical procedure performed to increase the volume of bone mass so that dental implants can be placed in the maxillary arch. Several materials have been suggested to be used for this procedure. The purpose of this study was to present the clinical and histologic results of using calcium sulfate with and without demineralized freeze-dried bone allograft (DFDBA) in sinus lift. Medical-grade sterile calcium sulfate was used alone or in combination with DFDBA in 6 patients undergoing sinus lift surgery for implant placement. Bone biopsies were taken at different times ranging from 6 to 24 months. All samples examined showed bone growth with some possible remnants of the grafted DFDBA. Implants were inserted either at the time of the lift or 6 months later. All of them were secure with primary stability. The cases reported indicate that calcium sulfate can be successfully used alone or in combination with DFDBA for sinus lift procedures and that possible residues of DFDBA can be found within newly generated bone. (Implant Dent 2004;13:270-277)Implant Dentistry 10/2004; 13(3):270-7. DOI:10.1097/01.id.0000136914.82891.20 · 1.18 Impact Factor