Bone Ingrowth to Ti Fibre Knit Block with High Deformability.
OBJECTIVE
The objective of this study is to develop a Ti fibre knit block without sintering, and to evaluate its deformability and new bone formationin vivo.


METHODS
A Ti fibre with a diameter of 150 μm was knitted to fabricate a Ti mesh tube. The mesh tube was compressed in a metal mould to fabricate porous Ti fibre knit blocks with three different porosities of 88%, 69%, and 50%. The elastic modulus and deformability were evaluated using a compression test. The knit block was implanted into bone defects of a rabbit's hind limb, and new bone formation was evaluated using micro computed tomography (micro-CT) analysis and histological analysis.


RESULTS
The knit blocks with 88% porosity showed excellent deformability, indicating potential appropriateness for bone defect filling. Although the porosities of the knit block were different, they indicated similar elastic modulus smaller than 1 GPa. The elastic modulus after deformation increased linearly as the applied compression stress increased. The micro-CT analysis indicated that in the block with 50% porosity new bone filled nearly all of the pore volume four weeks after implantation. In contrast, in the block with 88% porosity, new bone filled less than half of the pore volume even 12 weeks after implantation. The histological analysis also indicated new bone formation in the block.


CONCLUSIONS
The titanium fibre knit block with high porosity is potentially appropriate for bone defect filling, indicating good bone ingrowth after porosity reduction with applied compression.
Department of Biomaterials and Bioengineering, Tokushima University Graduate School of Oral Science, Tokushima Japan.
Yoko
Y
Henmi
Oral Implant Center, Tokushima University Hospital, Tokushima Japan.
Yoshihito
Y
Naito
Department of Oral and Maxillofacial Surgery and Oral Medicine, Malmö University, Malmö Sweden.
Ryo
R
Jimbo
Department of Oral and Maxillofacial Surgery and Oral Medicine, Malmö University, Malmö Sweden.
Yohei
Y
Jinno
Department of Biomaterials and Bioengineering, Tokushima University Graduate School of Oral Science, Tokushima Japan.
Kazumitsu
K
Sekine
Department of Biomaterials and Bioengineering, Tokushima University Graduate School of Oral Science, Tokushima Japan.
Kenichi
K
Hamada
biocompatible materials; bone formation; bone substitutes; elastic modulus; histological techniques; titanium