Cephalometry needs innovation, not renovation

Units of length, degree, and area are used when measuring cephalograms. In particular, the measurement of angles is a conventional method of quantifying shape. Because angles do not provide information about direction, there is no way to tell how and where one part of the facial structure has moved with respect to the rest. A new landmark data system using x- and y-coordinates is proposed, and some of its advantages over conventional methods are explained.