Transillumination in bite mark evidence

Transillumination of bite mark evidence is a technique whereby the presence of subcutaneous hemorrhage can be visualized without having to section through the bite mark. This is a nondestructive technique. The presence of subcutaneous hemorrhage indicates that the bite mark was inflicted before death or perimortem. In addition, the technique proves invaluable in determining the orientation of the bite mark. This is particularly helpful when a bite mark is poorly defined, barely visible, or obscured by other superimposed bite marks or traumatic injury patterns. Observation of the subcutaneous hemorrhage by transillumination may provide an indication of the horizontal alignment of the aggressor's dentition since the force of occlusion used in delivery of the bite mark is a factor in the presence and intensity of the hemorrhage. Transillumination supports a conclusion that there may be two types of hemorrhagic patterns in bite mark evidence. Lastly, when transillumination is used in conjunction with visual aids, it can facilitate communication of bite mark evidence to other expert witnesses or to the jury in trial presentation or both.