A composite photographic image - could it replace a lateral cephalogram?

Computer software allows a photograph of patient's face and a photograph of their dental casts to be combined into one image, similar to that seen in a lateral cephalogram. The aim of this study was to assess the agreement between the measurements carried out on this novel composite photographic image and those taken from a lateral cephalogram of the same patient.

The method involved the superimposition of a photograph of a patient's dental casts onto a photograph of their profile thus creating a composite image. The position of teeth in relation to the face was then compared on these images and on lateral cephalograms. The distances between a number of facial reference points to the upper right central incisor and the upper right last molar, were measured on both images.

The records of 34 participants showed that there was good or acceptable agreement between measurements carried out on composite images and on lateral cephalograms. This agreement was generally better for measurements carried out from the reference points to the incisor tooth than to the molar. However, standard deviations of the mean differences between measurements were relatively high.

The photographic superimposition method eliminates exposure to ionizing radiation and is relatively inexpensive. However, it is not reliable enough to deliver accurate information on the position of teeth in the face.