[Digital radiography].

The reliability of radiographical information may be improved by a) standardised radiography (exposure-development); b) transformation of the original image into a densitometric image and equalization with a reference wedge made of Ergal. The linear absorption coefficient of Ergal in terms of photon X energy is almost identical to the average coefficient of the bone mineral matrix; c) processing the densitometric image for additional information. An automatic image analyser controlled by a computer is used. The first osteological results showing the correspondence between the densitometric measurements provided by the analyser and the actual bone mineral content revealed by chemical analysis are presented.