Inter-operator reliability of overlay generation techniques in bite mark analysis

Overlays are representative of incisal edges of the teeth produced over transparent sheet. They are used most commonly for comparison of bite mark pattern of a suspect with that found on an animate or inanimate object. There are many techniques of overlay generation like the manual, photocopying and computer assisted techniques. With this background a study was conducted to evaluate various overlay generation techniques and to evaluate the inter-operator reliability in comparing the overlays generated. Overlay production was done by manual, photocopying and computer assisted techniques. As two examiners conducted the observation in our study, we were able to find the inter-operator reliability of the overlays generated. The computer assisted overlays were found to give reliable results. Keywords: Inter-operator reliability, manual, photocopying, computer assisted technique, Photoshop software version 7, magical wand selection tool