[The preparation, structure evaluation and preliminary application of biomimetic biphasic calcium phosphate scaffold].
OBJECTIVE
To fabricate biomimetic biphasic calcium phosphate BCP ceramic scaffolds using three-dimensional (3D) gel-lamination technology and evaluated their structure with 3D parameters and related method.


METHODS
Series two-dimensional images of femoral head's specimen of dogs were obtained by micro-computed tomography (Micro-CT). According to these images, porous biomimetic biphasic calcium phosphate (BCP) ceramic scaffolds with oriented trabecular structure were fabricated by three-dimensional (3D) gel-lamination technology. And then, the three-dimensional structure of the scaffolds were reconstructed by computer according to Micro-CT images of these scaffolds and evaluated by three-dimensional parameters. These parameters included bone volume fraction (BVF, BV/TV), bone surface/bone volume (BS/BV) ratio, trabecular thickness (Tb.Th), trabecular number (Tb.N), trabecular spacing (Tb.Sp) and structure model index (SMI). The biomechanical properties and biocompatibility of these scaffolds were also evaluated in the study. Six scaffolds, which were combined with BMCs (bone mesenchymal cells, BMCs), were planted into the bone defect of six dogs' femoral head respectively.


RESULTS
There was no significant difference between trabecular samples and BCP scaffolds in BV/TV, Tb.Th, Tb.N, and Tb.Pf (P > 0.05). The trabecular system of the scaffold, which had some orientation, represented plate-like model. With a micro-porous porosity of 62%, the average compressive modulus and ultimate strength along the axis of the scaffolds reached (464.0 +/- 36.0) MPa and (5.6 +/- 0.8) MPa respectively. The results of animal test indicated that the trabeculae of these scaffolds were covered by a layer of new bone after 10 weeks of operation.


CONCLUSIONS
Porous BCP scaffolds have been produced with oriented microarchitectural features designed to facilitate vascular invasion and cellular attachment and with initial mechanical properties comparable to those of trabecular bone.
Peng
Jiang
J
Institute Orthopeadics of People Liberation Army General Hospital, Beijing 100853, China.
Wang
Ai-yuan
AY
Sun
Ming-xue
MX
Xu
Wen-jing
WJ
Huang
Jing-xiang
JX
Zhao
Bin
B
Zhang
Li
L
Tian
Jie-mo
JM
Dong
Li-min
LM
Lu
Shi-bi
SB
D000818:Animals; D032701:Biomimetics / Q000379:methods*; D018786:Bone Substitutes / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D004285:Dogs; D005260:Female; D008297:Male; D008422:Materials Testing; D019919:Prosthesis Implantation; D013329:Structure-Activity Relationship; D023822:Tissue Engineering
D018786:Bone Substitutes; D002130:Calcium Phosphates; C020243:calcium phosphate