Repair of rabbit femoral condyle bone defects with injectable nanohydroxyapatite/chitosan composites

Abstract

Repair of massive bone loss remains a challenge to the orthopaedic surgeons. Autologous and allogenic bone grafts are choice for bone reconstructive surgery, but limited availability, risks of transmittable diseases and inconsistent clinical performances have prompted the development of tissue engineering. In the present work, the bone regeneration potential of nanohydroxyapatite/chitosan composite scaffolds were compared with pure chitosan scaffolds when implanted into segmental bone defects in rabbits. Critical size bone defects (6 mm diameter, 10 mm length) were created in the left femoral condyles of 43 adult New Zealand white rabbits. The femoral condyle bone defects were repaired by nanohydroxyapatite/chitosan compositions, pure chitosan or left empty separately. Defect-bridging was detected by plain radiograph and quantitative computer tomography at eight and 12 weeks after surgery. Tissue samples were collected for gross view and histological examination to determine the extent of new bone formation. Eight weeks after surgery, more irregular osteon formation was observed in the group treated with nanohydroxyapatite/chitosan composites compared with those treated with pure chitosan. 12 weeks after surgery, complete healing of the segmental bone defect was observed in the nanohydroxyapatite/chitosan-group, while the defect was still visible in the chitosan-group, although the depth of the defect had diminished. These observations suggest that the injectable nanohydroxyapatite/chitosan scaffolds are potential candidate materials for regeneration of bone loss.

Electrospun Poly (3-Hydroxybutyrate-co-3-Hydroxyvalerate)/Hydroxyapatite Scaffold With Unrestricted Somatic Stem Cells for Bone Regeneration

“…Zhang et al 44 developed an injectable nano-HAp/chitosan scaffold for repairing rabbit femoral condyle bone defects with critical size bone defects (6 mm in diameter and 10 mm in length). Twelve weeks after surgery, complete healing of the segmental bone defect was observed in the nano-HAp/chitosan group, whereas the defect was still visible in the chitosan group, although the depth of the defect had diminished.…”

Comparative study of porous hydroxyapatite/chitosan and whitlockite/chitosan scaffolds for bone regeneration in calvarial defects

“…Whitlockite (WH: Ca 18 Mg 2 (HPO 4 ) 2 (PO4) 12 ), a second most abundant mineral in living bone (about 20% based on the amount of Mg substitution of calcium ions with magnesium ions in calcium orthophosphate crystal. [11][12][13] Recently, Jang et al 14 evaluated the bioactive properties of WH nanoparticles through in vitro and in vivo tests and compared the results with those of HAP and β-tricalcium phosphate (β-TCP; β-Ca 3 (PO 4 ) 2 ).…”

“…Chitosan, an ideal biomaterial with excellent biocompatibility and antibacterial capability, has been widely applied in tissue engineering and bone repair. [15][16][17][18][19] Therefore, we chose chitosan as the organic phase to fabricate the inorganic/organic composite porous scaffold for bone regeneration. First, we prepared HAP and WH hollow microspheres by using creatine phosphate (CP) disodium salt as an organic phosphorus source in aqueous solution by microwave-assisted hydrothermal method.…”

Biodegradable composite scaffolds of bioactive glass/chitosan/carboxymethyl cellulose for hemostatic and bone regeneration

“…Chitosan is substitute material for bone defects because of its high biocompatibility, osteoconductivity, antimicrobial, biodegradability and adsorption properties (Zhang et al 2012). Bioactive glass can bond spontaneously to living bones without forming fibrous tissue at the interface (Shi et al 2007).…”

“…Zhang et al (2012) suggested that an injectable nanohydroxyapatite/chitosan scaffold was a potential candidate material for regeneration of bone loss. Vestergaard et al (2010) indicated that the use of Ostene instead of bone wax could contribute to a reduction in the incidence of sternal dehiscence and chronic inflammation.…”