The effect of crystallinity on strength development of alpha-TCP bone substitutes.

Research output: Contribution to journalArticle

Abstract

Alpha phase tricalcium phosphates (alpha-TCP) were produced using a solid-state reaction method and milled for various periods of time. The resulting four materials were alpha-TCPs, ranging in crystalline content. Powders were exposed to X-ray diffraction for material identification as well as for use in crystallinity and purity calculations. Powder particle size was investigated using laser diffraction. Materials were mixed with 2.5% Na2HPO4 solution to initiate the hydration of alpha-TCP to calcium-deficient hydroxyapatite (CDHA). Isothermal calorimetry was performed to observe thermal response of the powders over a period of time. During the reaction process, at various time points up to 216 h, the material was compression tested to observe strength development. Materials proved to be predominantly alpha phase, while amorphous content determined by XRD varied. Reactivity, as measured by isothermal calorimetry, varied with crystallinity of the alpha-TCP powder. Speed of strength development did not change except for the most finely ground powder. In addition, crystal size of the CDHA was changed only in the product formed from the most highly ground material. It is proposed that increasing reactivity of alpha-TCP cements does not result in a corresponding increase in rate of strength development until there is sufficient supersaturation to produce significant crystal nucleation.

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Authors
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Orthopedics

Keywords

  • calcium phosphate, reactivity, calcium-deficient hydroxyapatite, thermal properties/calorimetry, mechanical strength
Original languageEnglish
Pages (from-to)159-165
JournalJournal of Biomedical Materials Research. Part B - Applied Biomaterials
Volume79B
Issue number1
Publication statusPublished - 2006
Publication categoryResearch
Peer-reviewedYes

Bibliographic note

The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Polymer and Materials Chemistry (LTH) (011001041), Department of Orthopaedics (Lund) (013028000)