RESONANCE FREQUENCY TECHNIQUE TO DETERMINE ELASTIC-MODULUS OF HYDROXYAPATITE

A resonance frequency technique was applied to determine the elastic modulus of hydroxyapatite. A Free—Free Vibration Transducer was designed to determine elastic modulus in a longitudinal direction. A Fixed—Free Vibration Transducer was also designed to study elastic modulus of materials where specimens longer than 3 cm in length were not available. Six lots of hydroxyapatite were prepared utilizing the same process. The elastic modulus of hydroxyapatite varied between 3.94 × 1010 (dyn/cm2) and 6.30 × 1010 (dyn/cm2) in a longitudinal direction. For the same six lots, it varied between 1.95 × 1010 (dyn/cm2) and 3.20 × 1010 (dyn/cm2) in a cross direction. The elastic modulus values of cortical bone from dog tibias, fibulas, and femurs were also determined. Copyright © 1979 John Wiley & Sons, Inc.