title: Strengthening of calcium phosphate cement by compounding calcium carbonate whiskers.
abstract: The purpose of this study was to investigate how aragonite (calcium carbonate) whiskers influenced the strengthening and carbonating of alpha-tricalcium phosphate (alpha-TCP) based calcium phosphate cement. Aragonite whiskers of 0.95 microm width with an aspect ratio of 6.6 were prepared. The cement powder, alpha-TCP containing 0-50 mass% aragonite whisker, was mixed with 0.6 mol/L NaH2PO4 solution and incubated at 37 degrees C and 100% relative humidity. Diametral tensile strength (DTS) value increased significantly when appropriate amount of aragonaite whiskers was added. For example, DTS value of set cement containing 20 mass% aragonite whisker was 5.8 +/- 0.5 MPa, whereas DTS value of set cement containing no whiskers was 1.3 +/- 0.2 MPa after 1-week incubation. SEM observation revealed that the shape of the whiskers and the densification of the structure could have contributed to the strengthening of the set cement. Moreover, FTIR spectra implied that a bone-like carbonated apatite was precipitated in the cement. The results obtained in the present study revealed that the shape as well as any slight dissolution of aragonite whiskers could contribute to improving the properties of a-TCP based calcium phosphate cement.
authors.affiliation: Department of Biomaterials and Bioengineering, Institute of Health Biosciences, Tokushima University Graduate School, Tokushima, Japan. massy@dent.tokushima-u.ac.jp
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kon
authors.forename: Luciana M
authors.initials: LM
authors.lastname: Hirakata
authors.forename: Youji
authors.initials: Y
authors.lastname: Miyamoto
authors.forename: Hidemitsu
authors.initials: H
authors.lastname: Kasahara
authors.forename: Kenzo
authors.initials: K
authors.lastname: Asaoka
mesh_terms: D001031:Apatites / Q000032:analysis; D002119:Calcium Carbonate; D002130:Calcium Phosphates / Q000737:chemistry*; D002244:Carbon; D000077482:Carbon Fiber; D018360:Crystallography, X-Ray; D003738:Dental Cements / Q000737:chemistry*; D003799:Dental Stress Analysis; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D017550:Spectroscopy, Fourier Transform Infrared; D013718:Tensile Strength
chemical_list: D001031:Apatites; D002130:Calcium Phosphates; D000077482:Carbon Fiber; D003738:Dental Cements; D002244:Carbon; D002119:Calcium Carbonate; C018392:tricalcium phosphate