TY - JOUR
T1 - Is hydroxyapatite cement an alternative for allograft bone chips in bone grafting procedures? A mechanical and histological study in a rabbit cancellous bone defect model
AU - Voor, M.J.
AU - Arts, J.J.C.
AU - Klein, S.A.
AU - Walschot, L.H.B.
AU - Verdonschot, N.
AU - Buma, P.
PY - 2004/11/15
Y1 - 2004/11/15
N2 - To evaluate in vivo performance of hydroxyapatite cement (HAC) as a porous bone graft substitute, HAC was mixed (1:1 ratio) with either porous calcium-phosphate granules (80% tricalcium phosphate, 20% hydroxyapatite) or defatted morsellized cancellous bone (MCB) allograft and implanted bilaterally in cylindrical drill holes in distal femurs of rabbits. Groups with empty defects and impacted MCB were used for reference. After 8 weeks, one femur from each pair was examined histologically. All contralateral specimens and Time-0 specimens were used for mechanical indentation tests. Histology showed that some empty defects were filled with newly formed osteopenic bone after 8 weeks. The impacted MCB showed remodeling into new vital bone. Incorporation of the HAC/MCB composite was incomplete, whereas minimal new bone ingrowth was found in the HAC/granule composites. Though not different from each other, both composites were significantly stronger than empty defects, incorporated impacted MCB, and intact cancellous bone. At Time 0, the mechanical behavior of impacted MCB was similar to both HAC composites. In conclusion, composites of HAC and porous biomaterials can maintain relatively high strength over 8 weeks in vivo, but their incorporation into a new bony structure is slower than impacted MCB. The HAC/MCB composite showed favorable incorporation behavior.
AB - To evaluate in vivo performance of hydroxyapatite cement (HAC) as a porous bone graft substitute, HAC was mixed (1:1 ratio) with either porous calcium-phosphate granules (80% tricalcium phosphate, 20% hydroxyapatite) or defatted morsellized cancellous bone (MCB) allograft and implanted bilaterally in cylindrical drill holes in distal femurs of rabbits. Groups with empty defects and impacted MCB were used for reference. After 8 weeks, one femur from each pair was examined histologically. All contralateral specimens and Time-0 specimens were used for mechanical indentation tests. Histology showed that some empty defects were filled with newly formed osteopenic bone after 8 weeks. The impacted MCB showed remodeling into new vital bone. Incorporation of the HAC/MCB composite was incomplete, whereas minimal new bone ingrowth was found in the HAC/granule composites. Though not different from each other, both composites were significantly stronger than empty defects, incorporated impacted MCB, and intact cancellous bone. At Time 0, the mechanical behavior of impacted MCB was similar to both HAC composites. In conclusion, composites of HAC and porous biomaterials can maintain relatively high strength over 8 weeks in vivo, but their incorporation into a new bony structure is slower than impacted MCB. The HAC/MCB composite showed favorable incorporation behavior.
KW - Bone graft
KW - Calcium-phosphate cement
KW - Hydroxyapatite composite
KW - Mechanical test
KW - Osseointegration
UR - http://www.scopus.com/inward/record.url?scp=7744243683&partnerID=8YFLogxK
U2 - 10.1002/jbm.b.30109
DO - 10.1002/jbm.b.30109
M3 - Article
C2 - 15389506
AN - SCOPUS:7744243683
VL - 71
SP - 398
EP - 407
JO - Journal of Biomedical Materials Research, Part B: Applied Biomaterials
JF - Journal of Biomedical Materials Research, Part B: Applied Biomaterials
SN - 1552-4973
IS - 2
ER -