Bone regeneration with a collagen model polypeptides/α-tricalcium phosphate sponge in a canine tibia defect model
Related Experiment Video
Updated: Apr 16, 2026

Establishment and Evaluation of a Sheep Model of Full-thickness Osteochondral Defect
Published on: April 14, 2026
Tomohiko Ito1, Yoshiya Hashimoto, Shunsuke Baba
1*First Department of Oral and Maxillofacial Surgery, Osaka Dental University, Osaka, Japan. †Department of Biomaterials, Osaka Dental University, Osaka, Japan. ‡Department of Oral Implantology, Osaka Dental University, Osaka, Japan.
Introduction:
We evaluated the effects of synthesized collagen model polypeptides consisting of a proline-hydroxyproline-glycine (poly(PHG)) sequence combined with porous alpha-tricalcium phosphate (α-TCP) particles on bone formation in a canine tibia defect model.
Materials And Methods:
The porous α-TCP particles were mixed with a poly(PHG) solution, and the obtained sponge was then cross-linked and characterized by x-ray diffraction and scanning electron microscopy. Tibia defects were analyzed in 12 healthy beagles using microcomputed tomography and histological evaluation.
Results:
At 2 and 4 weeks, the volume density of new bone was higher in the poly(PHG)/α-TCP group than in poly(PHG) alone group (P < 0.05); however, there was no difference at 8 weeks (P > 0.05). Histological evaluation at 4 weeks after implantation revealed that the poly(PHG) had degraded, and newly formed bone was present on the surface of the α-TCP particles. At 8 weeks, continuous cortical bone formation with a Haversian structure covered the top of the bone defects in both groups.
Conclusion:
This study demonstrates that the composite created using porous α-TCP particles and poly(PHG) is sufficiently adaptable for treating bone defects.

