Bone Tissue Regeneration by Collagen Scaffolds with Different Calcium Phosphate Coatings: Amorphous Calcium Phosphate and Low-Crystalline Apatite
Syama Santhakumar,
Ayako Oyane,
Maki Nakamura,
Yuto Yoshino,
Mohammed Katib Alruwaili,
Hirofumi Miyaji
Affiliations
Syama Santhakumar
Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
Ayako Oyane
Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
Maki Nakamura
Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
Yuto Yoshino
Department of Periodontology and Endodontology, Faculty of Dental Medicine, Hokkaido University, N13W7, Kita-ku, Sapporo, Hokkaido 060-8586, Japan
Mohammed Katib Alruwaili
Department of Periodontology and Endodontology, Faculty of Dental Medicine, Hokkaido University, N13W7, Kita-ku, Sapporo, Hokkaido 060-8586, Japan
Hirofumi Miyaji
Department of Periodontology and Endodontology, Faculty of Dental Medicine, Hokkaido University, N13W7, Kita-ku, Sapporo, Hokkaido 060-8586, Japan
Surface-mineralized collagen sponges have attracted much attention as scaffolds for bone tissue engineering. Recently, we developed amorphous calcium phosphate (ACP) and low-crystalline apatite coating processes on collagen sponges. In the present study, we applied these coating processes to granular collagen sponges (referred to as Col) to compare the bone tissue regeneration capabilities of ACP-coated and apatite-coated Col (referred to as Col-ACP and Col-Ap, respectively) using a rat cranial bone defect model. According to micro-CT and histological analyses, Col-Ap enhanced bone tissue regeneration compared to Col, whereas Col-ACP did not. These results not only demonstrated the superior bone tissue regeneration capability of Col-Ap, but also indicated limitations of the in vitro simulated body fluid (SBF) test used in our previous study. Despite the apatite-forming ability of Col-ACP in SBF, it was ineffective in improving bone tissue regeneration in vivo, unlike Col-Ap, most likely due to the quick resorption of the ACP coating in the defect site. The present results clarified the importance of the coating stability in vivo and revealed that the low-crystalline apatite coating was more beneficial than the ACP coating in the fabrication of surface-mineralized collagen sponges for use as bone tissue engineering scaffolds.
