Keramik- und Pulveranalytik
The phase purity of β-tricalcium phosphate bone graft substitute material is determined by X-ray diffraction (XRD). Data evaluation by state-of-the-art Rietveld refinement was adapted from ISO 13175-3 and ISO 13779-3 and is compliant with ASTM F1088.
Crystalline main phases are identified in ceramic and metallic samples by comparing an X-ray diffraction pattern (XRD) with a crystal structure database. Depending on the complexity of the diffraction pattern, phases of less than ten weight percent can be identified.
The residual moisture content is calculated from the weight loss after intense drying according to Ph. Eur. Monography 2.2.32. „Loss on drying“ 01/2008:20232.
This test setup determines the setting time and the maximum reaction temperature of exothermic cement reactions according to ASTM F451-99a (reapproved 2007).
This test determines the amount of dissolved material from ceramic products according to ISO 10993-14.
In a specifically developed test setup we analyze the cohesion of pastes and cements in an aqueous environment. The result reveals how fast a paste dissolves or disintegrates in water. The setup can analyze paste volumes from 0.5 to 10 ml at room temperature.
In the BET method (Brunauer, Emmet and Teller) we use gas adsorption to determine the specific surface of solids. The nitrogen adsorption at a temperature of liquid nitrogen is used as standard method.
Calcium phosphate bone graft substitute materials are tested for heavy metals and impurity elements using inductively coupled plasma - mass spectrometry (ICP-MS). The analysis includes As, Cd, Hg, Pb, Bi, Sb, Sn, Ag, Cu, Mo, Fe and Cr contents along with a simultaneous screening for 50 additional impurity elements according to the maximum limits defined in ISO 13175-3, ASTM F1088, F1185 and F1581.
The dissolution properties of resorbable calcium phosphate bone graft substitute materials are determined in an in vitro dissolution test according to ISO 13175-3, which provides pH changes and Ca release in the incubation solution.