The application of the finite element method to the analysis of craniofacial growth and form.

It has been shown previously that all customary methods of analysis of craniofacial skeletal growth, closely based on the techniques of roentgenographic cephalometry, share common geometric and conceptual constraints that make all such descriptions reference frame dependent; i.e., these descriptions vary with each method of registrations and superimposition (stacking) of growth cross-sections (x-rays). The use of the concepts of continuum mechanics, and of the numerical techniques of the finite element method, permit a reference frame invariant tensor description of growth. An example of this method is provided by the analysis of the growth of the rat neurocranium and maxillary complex in the period 13-49 days of age. The finite element method should find wide application in the description of cephalic growth, in normal and pathological conditions.