Combining particle size distribution and isothermal calorimetry data to determine the reaction kinetics of alpha-tricalcium phosphate-water mixtures.
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.
Bohner
Marc
M
Dr. H.C. Robert Mathys Foundation, Bischmattstrasse 12, Bettlach 2544, Switzerland. marc.bohner@rms-foundation.ch
Malsy
Anna K
AK
Camiré
Christopher L
CL
Gbureck
Uwe
U
D001672:Biocompatible Materials / Q000737:chemistry*; D018786:Bone Substitutes; D002130:Calcium Phosphates / Q000737:chemistry*; D002151:Calorimetry; D007700:Kinetics; D012995:Solubility; D014867:Water
D001672:Biocompatible Materials; D018786:Bone Substitutes; D002130:Calcium Phosphates; C485828:alpha-tricalcium phosphate; D014867:Water