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Author Spotlight: Establishing an Accurate Microhardness Testing Protocol for Craniofacial Tissues
Published on: April 26, 2024
Correlation of ultrasound microscopy and Vickers hardness measurements of human dentin and enamel - A pilot study
Mareike Warkentin1, Cora Freyse2, Olaf Specht3
1Department of Materials Science and Medical Engineering, Friedrich-Barnewitz-Strasse 4, 18119 Rostock, University of Rostock, Germany.
Objective:
To investigate if Vickers microhardness of dentin and enamel correlated with acoustic velocity c(l) or acoustic reflection from the sample's top (amplitude).
Methods:
Eight transversal sections of a sound human tooth were investigated with scanning acoustic microscopy (SAM) and Vickers microhardness measurements. Longitudinal acoustic velocity c(l), amplitude and microhardness MHV were evaluated and for each c(l) test point corresponding amplitude and MHV were linearly interpolated and graphically analyzed. Spearman rank order correlation (rS) was calculated (p<0.05).
Results:
c(l) was predominantly 6100-7000ms-1 in enamel and 3800-4600ms-1 in dentin and correlated significantly with MHV with 27-420 in enamel and 20-90 in dentin (rs=0,57). Amplitudes significantly correlated with MHV, too, but even better (rs=0,77).
Significance:
Acoustic velocity and amplitudes were appropriate to detect microhardness differences of dentin and enamel and certain value ranges of both could be assigned to certain MHV ranges. Further research is needed to differentiate more precisely between the different hard tooth tissues.
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