ABSTRACT
This chapter focuses on development of methods to impart controlled states of deformation to tissue samples in vitro. Mechanics of materials is a well-developed area considering both macroscopic and microscopic behavior of materials. Stress and strain are central concepts in strength of materials, and the concept of strength is coupled to an idea of the local stresses or strains causing immediate or cumulative damage at each material point. It is also fair to state that living tissues from a material science point-of-view are very different from the underlying assumptions of ductility, homogeneity and isotropy necessary for the von Mises criterion. Mechanical stimulation of growing tissue in two dimensions can conveniently take place on elastic membranes, such as the Flexcell well system. Deformation experiments with the Flexcell system have traditionally taken place using circular posts. An alternative loading mechanism, inspired by Hertz contact mechanics, was invented to enable imposition of sufficient strain to cause necrosis.
