title: Fabrication of macroporous carbonate apatite foam by hydrothermal conversion of alpha-tricalcium phosphate in carbonate solutions.
abstract: Bone consists of a mineral phase (carbonate apatite) and an organic phase (principally collagen). Cancellous bone is characterized by interconnecting porosity necessary for tissue ingrowth and nourishment of bone cells. The purpose of the present study was to fabricate macroporous carbonate apatite (CAP) blocks with interconnecting porosity as potential bone substitute biomaterials by hydrothermal conversion of alpha-TCP foam in carbonate solution. The fabrication of the macroporous CAP was accomplished in two steps: (1) preparation of alpha-TCP foams using polyurethane foams as templates, and (2) hydrothermal conversion at 200 degrees C of alpha-TCP foam in the presence of ammonium carbonate solutions of different concentrations. The maximum carbonate content of the resultant CAP foam was approximately 7.4 wt %. The mean porosity of the CAP foam was as high as 93 vol %. The macroporous CAP blocks or granules prepared in this manner has properties similar to that of bone in mineral composition and in having interconnecting macroporosity necessary for osteoconductivity and tissue ingrowth. On the basis of composition and interconnecting macroporosity, the CAP foam materials could be ideal biomaterials for bone repair and as scaffolds for tissue engineering.
authors.affiliation: Faculty of Dental Science, Department of Biomaterials, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Wakae
authors.forename: A
authors.initials: A
authors.lastname: Takeuchi
authors.forename: K
authors.initials: K
authors.lastname: Udoh
authors.forename: S
authors.initials: S
authors.lastname: Matsuya
authors.forename: M L
authors.initials: ML
authors.lastname: Munar
authors.forename: R Z
authors.initials: RZ
authors.lastname: LeGeros
authors.forename: A
authors.initials: A
authors.lastname: Nakasima
authors.forename: K
authors.initials: K
authors.lastname: Ishikawa
mesh_terms: D001031:Apatites / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry*; D018786:Bone Substitutes / Q000737:chemistry; D002130:Calcium Phosphates / Q000737:chemistry*; D002254:Carbonates / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D011140:Polyurethanes / Q000737:chemistry; D016062:Porosity; D013696:Temperature
chemical_list: D001031:Apatites; D001672:Biocompatible Materials; D018786:Bone Substitutes; D002130:Calcium Phosphates; D002254:Carbonates; D011140:Polyurethanes; C485828:alpha-tricalcium phosphate; C030782:carboapatite; C028279:polyurethane foam