Gj. Ettinger et al., DEVELOPMENT OF AUTOMATED REGISTRATION ALGORITHMS FOR SUBTRACTION RADIOGRAPHY, Journal of clinical periodontology, 21(8), 1994, pp. 540-543
An algorithm is described which provides necessary information for aut
omated registration and computation of alveolar height for subtraction
radiographic analysis. This procedure involves identification of the
cemento-enamel junctions from radiographic images by incrementally com
paring a characteristic image signature along computed tooth boundarie
s. The identification of these anatomically invariant structures provi
des information necessary to warp images and create automatic superimp
osition, correcting for geometric misalignment. The present report des
cribes and demonstrates the feasibility of utilizing automated CEJ, ed
ge finding and image warping algorithms to align automatically sequent
ial radiographs and permit their subtraction.