THE PRACTICABILITY OF FINITE-ELEMENT ANALYSIS FOR ASSESSING CHANGES IN HUMAN CRANIOFACIAL MORPHOLOGY FROM CEPHALOGRAPHS

The usefulness of a finite-element analytical (FEA) method for studyin g changes in facial form was investigated. The material was lateral ce phalographs of 19 patients who had undergone surgical correction of th e chin. FEA was used to assess changes in bony form brought about by s urgery. Replicate digitization of cephalographic landmarks was used to minimize measurement error. Random and systematic errors were examine d and their influence on the finite-element method was assessed. Howev er, the sensitivity of FEA is such that the level of residual measurem ent error affects the reliability of the method and makes the techniqu e unsuitable for individual cases. However, for pooled data from a gro up of cases the effect of measurement error is reduced and the reliabi lity of the analysis is satisfactory for intergroup comparison.