title: Combining particle size distribution and isothermal calorimetry data to determine the reaction kinetics of alpha-tricalcium phosphate-water mixtures.
abstract: Many calcium phosphate bone substitutes are based on the use of alpha-tricalcium phosphate (alpha-TCP) powder. This compound has been intensively studied, but some aspects of alpha-TCP reactivity are still controversial. The goal of this study was to determine the setting kinetics of alpha-TCP based on a new approach that compared particle size distribution data to isothermal calorimetry data. Results indicated that alpha-TCP conversion is mostly controlled by surface reactions, with at later stages a diffusion-controlled mechanism. The presence of an X-ray amorphous alpha-TCP fraction in the crystalline alpha-TCP powder increased the dissolution rate threefold, without modifying the reaction mechanism.
authors.affiliation: Dr. H.C. Robert Mathys Foundation, Bischmattstrasse 12, Bettlach 2544, Switzerland. marc.bohner@rms-foundation.ch
authors.forename: Marc
authors.initials: M
authors.lastname: Bohner
authors.forename: Anna K
authors.initials: AK
authors.lastname: Malsy
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Camiré
authors.forename: Uwe
authors.initials: U
authors.lastname: Gbureck
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D018786:Bone Substitutes; D002130:Calcium Phosphates / Q000737:chemistry*; D002151:Calorimetry; D007700:Kinetics; D012995:Solubility; D014867:Water
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D002130:Calcium Phosphates; C485828:alpha-tricalcium phosphate; D014867:Water