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Reduction and Fixation of Sacroiliac joint Dislocation by the Combined Use of S1 Pedicle Screws and an Iliac Rod
Published in Kai-Uwe Lewandrowski, Donald L. Wise, Debra J. Trantolo, Michael J. Yaszemski, Augustus A. White, Advances in Spinal Fusion, 2003
Kai-Uwe Lewandrowski, Donald L. Wise, Debra J. Trantolo, Michael J. Yaszemski, Augustus A. White
An alternative calcium phosphate cement (Mitsubishi Materials, Tokayo, Japan) has been examined by Ikeuchi et al. [67]. The CPC used in the study consisted of the cement [75% w/ w a-tricalcium phosphate (Ca3(PO4)2], 18% w/w tetracalcium phosphate [Ca4(PO4)2O], 5% w/ w dicalcium phosphate (CaHP04•H2O), and 2% w/w hydroxyapatite [Ca10(PO4)6(OH)2)] and a weakly basic hardening liquid (5% w/w chondroitin sodium sulfate, 12% w/w sodium succinate, 83% w/w water). The material in the study was prepared with a powder-to-liquid ratio of 2.8. The material was kneaded for 7 minutes to form a paste-like substance which was easy to infuse with a syringe and had a durable strength. The material progressively hardens to form hydroxyapatite by a hydration reaction. The resultant material has a compressive strength of about 80 MPa 1 week after hardening. The hardening characteristics of the cement vary with the weight ratios of the powder and liquid components. The material has been shown to be osteoconductive in vivo and bonds to newly formed bone. The results of the study showed that strength could be increased by using the CPC. Further, they showed an increase in strength with an increase in fill volume. Nevertheless, the CPC was utilized in this study as a prophylactic treatment of osteoporotic vertebral bodies at risk of fracture, therefore, the use of a ‘weaker’ material compared to PMMA may be beneficial in order to prevent stress-riser.
Injectable Scaffolds for Bone Tissue Repair and Augmentation
Published in Naznin Sultana, Sanchita Bandyopadhyay-Ghosh, Chin Fhong Soon, Tissue Engineering Strategies for Organ Regeneration, 2020
Subrata Bandhu Ghosh, Kapender Phogat, Sanchita Bandyopadhyay-Ghosh
In one study, compressive elastic modulus (E) and shear modulus (G) of nanocomposite hydrogels comprised of calcium alginate hydrogel and nano-hydroxyapatite/collagen was found to be dependent on alginate concentration, although, the variations were not linear (ParameswaranThankam et al. 2018). This could be attributed to change in cross-linking density with increasing concentration of alginate. However, it was also reported that the presence of nHAC and Ca3(PO4)2 particles could result in stress concentration and reduction of mechanical strength (Tan et al. 2009). Biphasic calcium phosphate mixed with silated hydroxypropylmethyl cellulose (Si-HMPC) has been used as an injectable bone substitute. The yield strength of the hydrogel composite (16.4 ± 7.2 MPa) was reported to be significantly higher than for the host trabecular bone tissue (2.7 ± 0.4 MPa) (Chang and Zhang 2011). Liu et al. developed an injectable bone scaffold composed of chitosan, citric acid and glucose solution based matrix and tetracalcium phosphate powder as the reinforcement. When the concentration of citric acid was increased, the compressive strength of the specimen was found to be increased. Addition of the carbon nanotubes (CNTs) to chitosan hydrogel also has been reported to increase the compressibility of the materials and Young’s modulus, which could be attributed to higher cross-linking density, reinforcing effect of CNTs and their uniform dispersion in the polymer matrix. Similarly, reinforcement of β-TCP and CaCO3 have been reported to increase both the compressive modulus and the maximum compressive strength of injectable composites of poly [D, L-lactide-co-(ε-caprolactone)]. The compressive strain at break was also found to decrease with increasing filler loading (Liu et al. 2009, López et al. 2010).
Injectable Scaffolds for Oral Tissue Regeneration
Published in Vincenzo Guarino, Marco Antonio Alvarez-Pérez, Current Advances in Oral and Craniofacial Tissue Engineering, 2020
J.L. Suárez-Franco, B.I. Cerda-Cristerna
Chitosan-Based Injectable Scaffolds (ChBIS) have been explored because of its properties for inducing bone repairing. A ChBIS loaded with calcium phosphate cement tetracalcium phosphate and dicalcium phosphate anhydrous has shown to be useful for bone regeneration (Moreau and Xu 2009). The chitosan gave important flexural strength and elastic modulus to the injectable scaffold. Rat bone-marrow-derived Mesenchymal Stem Cells (MSCs) adhered on the scaffold and showed a normal polygonal morphology, the attaching of the cells was noticed for its cytoplasmatic extension and cell-cell junctions were also observed. After 14 days of contact, the MSCs showed a 99% of viability. The ALP activity increased and the MSCs were differentiated into an osteogenic lineage (Moreau and Xu 2009). The ChBIS have also been formulated with alginate beads (A1B) loaded with human Umbilical Cord Mesenchymal Stem Cells (hUCMSCs). The alginate beads (73-465 rim; mean diameter 207 lam) gave important flexural strength to the scaffold as well as elastic modulus and work-of-fracture; the ChBIS-A1B was also easily injectable from a 10-gauge needle. The hUCMSCs were viable for 14 days (longest experimental time) and the same number of days was observed for an important ALP activity. Very interestingly, the hUCMSCs caused showed mineral synthesis with an increase from day 1 to day 14 (Zhao et al. 2010). The HydroMatrix® hydrogel has been investigated as a scaffold for human Periodontal Ligament Stem Cells (hPDLSCs) (Nagy et al. 2018). The cells proliferated in the hydrogel, and also showed adhesion on the surface. Cell viability with a fibroblast-like morphology was observed at 24 hours, 48 hours and 72 hours. The ALP activity increased from day 7 to day 21, and the osteogenic differentiation of PDLSCs was identified because of gene expression of ALP, Runx2 and osterix. Very interesting, mineralized nodules were detected on the scaffold after 14 days (Nagy et al. 2018). Hence, commercial and home-made injectable scaffolds are able to promote in vitro regeneration of bone.
Recent Advances in Biomaterials for the Treatment of Bone Defects
Published in Organogenesis, 2020
Le-Yi Zhang, Qing Bi, Chen Zhao, Jin-Yang Chen, Mao-Hua Cai, Xiao-Yi Chen
To enhance bone formation, mechanical strength, and the functional performance of large bone defects, Oryan et al. assessed the regenerative potential of Ca2+ silicate biomaterials produced by reacting calcium oxide and silica in various ratios in combination with the linear polysaccharide chitosan.63 The bilaterally implanted Ca2+ silicate bio-implants greatly improved radial bone healing and growth. Lui et al. similarly produced bioactive tetracalcium phosphate/magnesium phosphate composite bone cements that enhanced bone repair.51 Importantly, these materials were biodegradable. In alternative approaches, Munoz and colleagues demonstrated that non-setting injectable biomaterials loaded with ceramic particles enhance the stability of bone screws.64 These materials were unique as they permitted screw augmentation without impairing or favoring bone formation in a particular direction around the screw. This approach is principally advantageous for treating osteoporotic fractures that require screw stabilization.
Injectable calcium phosphate scaffold with iron oxide nanoparticles to enhance osteogenesis via dental pulp stem cells
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Yang Xia, Huimin Chen, Feimin Zhang, Lin Wang, Bo Chen, Mark A. Reynolds, Junqing Ma, Abraham Schneider, Ning Gu, Hockin H. K. Xu
Calcium phosphate cements are promising scaffolds for use in craniofacial and orthopaedic repairs, including the reconstruction of frontal sinus, augmentation of craniofacial skeletal defects, use in endodontics and the repair of periodontal bone defects [20,21]. The powder phase can be mixed with an aqueous liquid to form a paste that can be sculpted during surgery to conform to the defects in hard tissues. The paste self-hardens to form resorbable hydroxyapatite (HA) [22]. Calcium phosphate cements have many advantages, including self-setting in vivo without producing heat, conformation to osseous defects with complex shapes, inexpensive and relatively easy to fabricate. The first calcium phosphate cement to win the approval of the Food and Drug Administration (FDA) was based on tetracalcium phosphate [TTCP: Ca4(PO4)2 O] and dicalcium phosphate anhydrous [DCPA: CaHPO4] (referred to as CPC) [23]. In addition, there were other calcium phosphate cements with different compositions [24,25].