[Histological and biomechanical study of repairing rabbit radius segmental bone defect with porous titanium].
OBJECTIVE
To investigate the therapeutic effects of porous titanium (Ti) on the recovery of rabbit radial bone defect.


METHODS
Bone defects were  artificially made in 30 New Zealand rabbits by resecting the 1 cm substantial osseo with periosteum of both radii. The left anterior limbs were implanted with  porous titanium, while the right anterior limbs with porous hydroxyapatite (HA). The rabbits were sacrificed at three time points. Both the radii healing  statuses were observed by histology and histomorphometry analyses by means of computer graphic processing at the end of 8, 12 and 24 weeks, and  biomechanical analyses at the end of 12 and 24 weeks.


RESULTS
The histology examination showed that mass newly formed bone had grown into most  pores of both the specimens. Along with prolongation of times after operation, the ingrowths of bone cells and effects of bone remodeling in the research  side were nearly the same as those in the control side at the end of 12 and 24 weeks. The interface between the new bone and implants showed tight  contact in both the groups without an obvious fibrous tissue. The results of histomorphometrical analyses showed that a statistically significant difference  was not obtained for % bone area (bone area/ gross implant) between both the groups (P>0.05).However, the results of maximum failure load for the Ti  group and the HA group were (107.34±27.44) N and (93.42±21.18) N at the end of 12 weeks, (118.56±24.65) N and (102.15±23.37) N at the end of 24 weeks,  respectively. Biomechanical properties of the Ti group was stronger than that of the HA group, however, a statistically significant difference was not  obtained between both the groups (P=0.102).


CONCLUSIONS
Porous titanium scaffold can promote the formation of new bone, which contributes to the  healing of long tubular bone defect. The porous titanium can enhance the bone repairing effect on segmental bone defect nearly the same as porous  hydroxyapatite .
Department of Orthopedics, West China Hospital, Sichuan University, Chengdu 610041, China.
Hong-fang
HF
Zhang
Chao-yong
CY
Zhao
Hong-song
HS
Fan
Hui
H
Zhang
Fu-xing
FX
Pei
Guang-lin
GL
Wang
D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D001861:Bone Regeneration; D018786:Bone Substitutes / Q000627:therapeutic use*; D008297:Male; D016062:Porosity; D019736:Prostheses and Implants; D011817:Rabbits; D011884:Radius / Q000293:injuries* / Q000601:surgery; D054457:Tissue Scaffolds / Q000737:chemistry; D014025:Titanium / Q000737:chemistry*
D001672:Biocompatible Materials; D018786:Bone Substitutes; D014025:Titanium