title: Improved bioabsorbability of synthetic hydroxyapatite through partial dissolution-precipitation of its surface.
abstract: Even though synthetic hydroxyapatite (HAp) has a chemical composition similar to the mineral phase of bone, it is minimally absorbed and replaced by bone tissue. This could be because HAp is composed of compactly arranged apatite crystals with homogenously large grains. In this study, the surface and non-stoichiometry of the synthetic HAp crystals was modified by partial dissolution and precipitation (PDP) to improve bioabsorbability of HAp. In vitro cell culture demonstrated that more osteoclasts were activated on PDP-HAp compared with HAp. In vivo implantation using a rabbit bone defect model revealed that PDP-HAp was gradually degraded and was replaced by bone tissue. Consistent with the in vitro results, more osteoclasts were activated in PDP-HAp than in HAp, indicating that the former was absorbed through the stimulation of osteoclastic activity. These results suggest that the PDP technique may have clinical utility for modifying synthetic HAp for use as superior bone graft substitutes.
authors: Department of Orthopedic Surgery, Graduate School of Medicine, Hokkaido University, Kita-15 Nishi-7, Kita-ku, Sapporo, 060-8638, Japan.
authors: Xianjun
authors: X
authors: Ding
authors: Masahiko
authors: M
authors: Takahata
authors: Toshiyuki
authors: T
authors: Akazawa
authors: Norimasa
authors: N
authors: Iwasaki
authors: Yuichiro
authors: Y
authors: Abe
authors: Miki
authors: M
authors: Komatsu
authors: Masaru
authors: M
authors: Murata
authors: Manabu
authors: M
authors: Ito
authors: Kuniyoshi
authors: K
authors: Abumi
authors: Akio
authors: A
authors: Minami
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D001846:Bone Development / Q000502:physiology; D001854:Bone Marrow Cells / Q000502:physiology; D001842:Bone and Bones / Q000293:injuries; D049109:Cell Proliferation; D017886:Durapatite / Q000737:chemistry*; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology; D051379:Mice; D010006:Osteoblasts / Q000502:physiology; D015649:Pentostatin; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011817:Rabbits; D013499:Surface Properties
chemical_list: D012333:RNA, Messenger; D015649:Pentostatin; D017886:Durapatite