Bitemark determination in forensic odontology is commonly performed by comparing the morphology of the dentition of the suspect with life-sized photographs of injury on the victim's skin using transparent overlays or computers. The purpose of this study is to investigate the suitability of two new different methods for identification of bitemarks by digital analysis. A sample of 50 volunteers was asked to make experimental bitemarks on the arms of each other. Stone study casts were prepared from upper and lower dental arches of each volunteer. The bitemarks and the study casts were photographed; the photos were entered into the computer and Adobe Photoshop software program was applied to analyze the results. Two methods (2D polyline and Painting) of identification were used. In the 2D polyline method, fixed points were chosen on the tips of the canines and a straight line was drawn between the two fixed points in the arch (intercanine line). Straight lines passing between the incisal edges of the incisors were drawn vertically on the intercanine line; the lines and angles created were calculated. In the painting method, identification was based on canine-to-canine distance, tooth width and the thickness, and rotational value of each tooth. The results showed that both methods were applicable. However, the 2D polyline method was more convenient to use and gave prompt computer-read results, whereas the painting method depended on the visual reading of the operator.

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Abstraet. Cysts lined by epithelium were often found in association with tooth-germ isografts in hamster cheek pouch. They developed from odontogenic epithelium and were in close relation to the crowns of involved teeth. Cysts associated with tooth-germ isografts from 5-day-old animals (17 out of 36) commenced their formation shortly after transplantation as a result of enamel organ degen tion. Teeth assoeiated with the.se cysts often showed enamel hypoplasia. Aeeordingly. 86 teeth involved in human dentigerous eysts were examined and 43 were found to possess areas of enamel hypoplasia on their oeelusal surfaces or ineisal edges. It is suggested that the pathologieal process initiating eystic degeneration in the enamel organ was also accompanied by degeneration of ameloblasts. When tooth-germs from 2-day-old hamsters were transplanted, eystic spaces developed only after completion of enamel formation, 6 weeks following transplantation (in six out of 11 transplants), as a result of separation between the cells of the redueed enamel epithelium. Enamel hypoplasia was not a conspicuous feature. These experimental and clinical observations suggest that there may be at least two types of dentigerous cyst, perhaps with dilTerent causes, arising at diflcrent stages of tooth development.

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