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Structured light scanning is a noninvasive, accurate, and cost‐effective 3D imaging technique, but due to reflection issues is yet to be utilized for tool mark analysis on fresh bone. During imaging, reflection from shiny surfaces, such as greasy bone, disrupts image formation. This study tested the David SLS‐1 scanner's ability to image saw marks and explored six strategies to reduce reflection by [1] dulling the surface or [2] altering the projected light. The surface was dulled by freezing, talcum powder, dulling spray, or compressed air. The projected light was altered with a diffuser or limited to single pattern‐coded. Results demonstrated that the resolution was insufficient for capturing minute details of striae. All six tests failed to reduce reflection sufficiently to produce complete images, but projecting vertical pattern‐coded light showed the most promise. Future research is required concentrating on enhancing resolution and exploring the role of pattern‐coded light in reducing reflection. [ABSTRACT FROM AUTHOR]

Validation studies of the new DentalPrint© software were carried out with experimental bite marks in pigskin. The bite marks were digitally photographed according to the ABFO guidelines for evidence collection. Dental casts used in the experiment were scanned in 3D and 2D, and comparison overlays were generated using DentalPrint© and Adobe® Photoshop® software, respectively. Digitized photographs of the experimental bite marks and the biting edges obtained in the overlays were compared by two different examiners to analyze the impact of training and experience with the two methods. Receiver operating characteristic (ROC) analysis, sensitivity, specificity, and 95% confidence intervals for each cutoff point were calculated. The expert examiner using DentalPrint© obtained the best results, with an area under the ROC curve of 0.76 (SE=0.057; CI at 95%=0.652–0.876). Fairly high specificity values were found for DentalPrint©, and the best results were obtained for the cutoff value that discriminated between the examiner's response “biter” and the rest of the possible (specificity 97.9%, CI at 95%=93.2%–99.6%). Therefore, the results presented here indicate that DentalPrint© is a useful, accurate tool for forensic purposes, although further research on the comparison process is needed to enhance the validity of bite mark analysis. [ABSTRACT FROM AUTHOR]

Presents a study which describes a new software package, DentalPrint, developed to generate comparison overlays from three-dimensional images of the suspect's dental casts. Importance of bite marks evidence found on the skin of a living person or a corpse and on objects in criminal investigations; Emphasis on the need for new three-dimensional (3D) imaging technologies in bite mark analysis; Presentation of the software package DentalPrint that generates different comparison overlays from 3D dental cast images depending on the pressure of the bite or the distortion caused by victim-biter interaction.