A SPECIMEN POSITIONING DEVICE FOR DENTAL RADIOGRAPHIC IDENTIFICATION - IMAGE GEOMETRY CONSIDERATIONS

Preventative dental treatment has reduced caries incidence and thereby rendered dental identification, in caries-free individuals, more diff icult. An alternate method comparing spatial relationships of dental s tructures in digitized superimposed antemortem and postmortem radiogra phs has been previously developed. This paper examined the limitations of this technique and demonstrates a positioning device suitable for reproducing antemortem radiographic image geometry. The paper also exa mined three specific aspects of image geometry namely horizontal angul ation, vertical angulation and focal film distance. Deviations in hori zontal angulations between antemortem and postmortem radiographs by as little as 5 degrees makes identification difficult. Changes in vertic al angulation or focal-film distance had no affect. This procedure, an d the positioning device used to accurately replicate antemortem image geometry is an economical, easy to use adjunct to current methods of dental identification.