title: Investigation of structural resorption behavior of biphasic bioceramics with help of gravimetry, μCT, SEM, and XRD.
abstract: Resorbable bone substitute materials are widely used for bone augmentation after tumor resection, parallel to implant placement, or in critical size bone defects. In this study, the structural dissolution of a biphasic calcium phosphate bone substitute material with a hydroxyapatite (HA)/tricalcium phosphate (β-TCP) ratio of 60/40 was investigated by repeatedly placing porous blocks in EDTA solution at 37 °C. At several time points, the blocks were investigated by SEM, µCT, and gravimetry. It was found that always complete 2-3 µm sized grains were removed from the structure and that the β-TCP is dissolved more rapidly. This selective dissolution of the β-TCP grains was confirmed by XRD measurements. The blocks were eroded from the outside toward the center. The structure remained mechanically stable because the central part showed a delayed degradation and because the slower dissolving HA grains preserved the integrity of the structure.
authors.affiliation: University of Applied Sciences Northwestern Switzerland, School of Life Sciences, Institute for Medical and Analytical Technologies, Muttenz, Switzerland.
authors.forename: Michael
authors.initials: M
authors.lastname: de Wild
authors.affiliation: University of Applied Sciences Northwestern Switzerland, School of Life Sciences, Institute for Medical and Analytical Technologies, Muttenz, Switzerland.
authors.forename: Fabienne
authors.initials: F
authors.lastname: Amacher
authors.affiliation: EMPA, Materials Technology, EMPA Thun, Switzerland.|Roche Diagnostics International Ltd, Rotkreuz, Switzerland.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Bradbury
authors.affiliation: Research and Testing, Institut Straumann AG, Basel, Switzerland.|DePuy Synthes, Oberdorf, Switzerland.
authors.forename: Aart
authors.initials: A
authors.lastname: Molenberg
mesh_terms: D002130:Calcium Phosphates / Q000737:chemistry*; D002516:Ceramics / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D014961:X-Ray Diffraction; D055114:X-Ray Microtomography
chemical_list: D002130:Calcium Phosphates; C485817:beta-tricalcium phosphate; D017886:Durapatite
keywords: bioceramic; hydroxylapatite; selective resorption; β-TCP; μCT/SEM/XRD