Critical-size bone defects

However, more recent work about using the PEG/PBT as a bone substimte in critical size defects in the iliac bone of goats and humans did not show the expected good bone-bonding and calcification behaviors. Reasons for the discrepancy with the earlier results in small animals may be caused by the differences in regenerative capacity between the species, the size of the defect, and the type of bone into which the substitute was implanted. 

Kirker-Head, C., Karageorgiou, V., Hofmann, S., Fajardo, R., Betz, O., Merkle, H.P., Hilbe, M., von Rechenberg, B., McCool, J., Abrahamsen, L., Nazarian, A., Cory, E., Curtis, M., Kaplan, D., and Meinel, L. "BMP-silk composite matrices heal critically sized femoral defects". Bone 41(2), 247-255 (2007). 

Liu, Y.L., Wu, G and de Groot, K. (2010) Biomimetic coatings for bone tissue engineering of critical-sized defects. / R. Soc. Interface, 7, S631-S647. 

A novel material made of biodegradable polymer reinforced with modified calcium phosphates (TCP) particles will be proposed to be used in fabrication of novel constructs for the repair of critical-sized bone defects. Several composite materials made of PLLA/PDLA or PCL reinforced with TCP micro and nanoparticles will be discussed. 

Yoon, E., Dhar, S., Chun, D. E., Gharibjanian, N. A., Evans, G. R. In vivo osteogenic potential of human adipose-derived stem cells/poly lactide-co-glycolic acid constructs for bone regeneration in arat critical-sized calvarial defect model. Tissue Engineering. 2007,13, 619-627. 

L. Meinel, R. Fajardo, S. Hofmann, R. Langer, J. Chen, B. Snyder, et al., Silk implants for the healing of critical size bone defects, [187] Bone 37 (2005) 688-698. 

Notodihardjo FZ, Kakudo N, Kushida S, Suzuki K, Kusumoto K. Bone regeneration with BMP-2 and hydroxyapatite in critical-size calvarial defects in rats. J Cranio Maxiiio Facial Suig 2012 40 287-91. 

Spicer, P.P., Kretlow, J.D., Young, S., Jansen, J.A., Kasper, F.K., Mikos, A.G., 2012. Evaluation of bone regeneration using the rat critical size calvarial defect. Nat. Protoc. 7, 1918-1929. 

Starecki M, Schwartz J, Grande D. Evaluation of amniotic-derived membrane biomaterial as an adjunct for repair of critical sized bone defects. Adv Orthop Surg 2014 572-86. 

The scaffolds favor bone regeneration in critical size calvarial defects in rats within [155] 8 weeks. The BMP-2 improves the osteoconductivity of the scaffolds, increasing expression of osteocalcin, BMP-2 and Smad5... 

Lin et al. tested the possibility of repairing large segmental bone defects (5 mm) in rats by developing a porous poly(L-lactide-co-D,L-lactide 7 3) (PLDL) scaffolds with a distinctive transversely isotropic oriented porosity. Defects were created bilaterally in rats and either filled with a PLDL scaffold or left empty. Bone formation was observed in some of the control empty defects, indicating that 5 mm is not a critically sized long bone defect in the rat. However, scaffold-treated defects contained 30% more bone than empty ones. 

Patel ZS, Young S, Tabata Y, Jansen JA, Wong MEK, Mikos AG. Dual dehvery of an angiogenic and an osteogenic growth factor for bone regeneration in a critical size defect model. Bone 2008 43(5) 931-40. 

T. L. Arinzeh, S. J. Peter, M. P. Archambault, B. C. Van Den, S. Gordon, K. Kraus, A. Smith and S. Kadiyala, Allogeneic mesenchymal stem cells regenerate bone in a critical-sized canine segmental defect. /. Bone joint Surg. Am. 85-A, 10,1927-1935 (2003). 

Dumas JE, et al. Injectable reactive biocomposites for bone healing in critical-size rabbit calvarial defects. Biomed Mater 2012 7(2) 024112. 

Chew S A, Kretlow JD, Spicer PP, Edwards AW, Baggett LS, Tabata Y, et al. Delivery of plasmid DNA encoding bone morphogenetic protein-2 with a biodegradable branched polycationic polymer in a critical-size rat cranial defect model. Tissue Eng Part A 2011 17(5-6) 751-63. 

Kasper FK, Young S, Tanahashi K, Barry MA, Tabata Y, Jansen JA, et al. Evaluation of bone regeneration by DNA release from composites of ohgo(poly(ethylene glycol) fumarate) and cationized gelatin microspheres in a critical-sized calvarial defect. J Biomed Mater Res A 2006 78(2) 335—42. 

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