title: Accelerated degradation and improved bone-bonding ability of hydroxyapatite ceramics by the addition of glass.
abstract: Dense hydroxyapatite (HA) ceramics are useful bone substitutes, but they degrade minimally. One solution is to incorporate degradable materials in the HA. In this study, we manufactured glass-containing HA and investigated whether the degradability and bone-bonding ability of the HA were improved. The glass-containing HA was manufactured from a mixture of HA powder and 1.0 wt% glass powder. The control HA was manufactured from pure HA powder. In vitro degradability was evaluated by soaking in physiological saline, and a rabbit model was used to evaluate in vivo degradability and bone-bonding ability. Detaching tests were performed for all removed samples to quantify bone-bonding ability of each type of HA. The glass-containing HA showed higher degradability than the control HA, both in vitro and in vivo. The detaching failure load of the glass-containing HA was rapidly elevated after implantation and was higher than that of the control HA. Our results suggest that the dissolution of the added glass made the glass-containing HA degradable and that the detaching failure load of the glass-containing HA was elevated by reinforcement of the mechanical locking at the roughened interface. Incorporation of glass additives into HA can be concluded to be a good candidate for producing a bone substitute that can partially degrade and bond to bone firmly and rapidly.
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan. so_kazu@kuhp.kyoto-u.ac.jp
authors.forename: Kazutaka
authors.initials: K
authors.lastname: So
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Fujibayashi
authors.forename: Masashi
authors.initials: M
authors.lastname: Neo
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Anan
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Ogawa
authors.forename: Tadashi
authors.initials: T
authors.lastname: Kokubo
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakamura
mesh_terms: D020341:Absorbable Implants; D000042:Absorption; D000268:Adhesiveness; D000818:Animals; D018786:Bone Substitutes / Q000737:chemistry* / Q000627:therapeutic use*; D002516:Ceramics / Q000737:chemistry / Q000627:therapeutic use; D017886:Durapatite / Q000737:chemistry* / Q000627:therapeutic use*; D005898:Glass / Q000737:chemistry; D008297:Male; D008422:Materials Testing; D011817:Rabbits; D013978:Tibial Fractures / Q000473:pathology* / Q000601:surgery*; D016896:Treatment Outcome
chemical_list: D018786:Bone Substitutes; D017886:Durapatite