Parameters influencing the sonic velocity in compact calcified tissues of various species

Abstract

Compact calcified tissues from a wide variety of [vertebrate] species were used in a study of the dependence of sonic plesio-velocity on physical parameters. A linear dependence of velocity on wet density had been found for each of 3 categories of wet mineralized tissue: compact long bone measured in the axial direction, compact long bone measured in the radial direction, and hyperpycnotic mineralized tissues. A similar linear dependency was found for dry calcified tissue using the dry density. In addition to these 3 parameters (density, orientation, and water content) 2 other factors were identified. The bone fibers in long bone matrix are ordered with respect to the bone axis and the anisotropy of long bone matches that of its matrix. There is no corresponding order to the fibers in hyperpycnotic tissue matrix. The 5th parameter is believed to be the porosity. Fish bone is much more porous than other compact bone from long bone and the sonic velocity in fish bone is much lower than for other bone. These parameters are not independent.