Transparent Overlay
Definition
A life-size tracing or printed representation of the biting surfaces of a suspect's dental cast, placed over a bite mark photograph to compare arch shape and individual tooth positions.
- Form
- Life-size tracing or print of a dental cast's biting surfaces
- Used for
- Comparing arch shape and individual tooth positions
- Applied to
- A bite mark photograph
- Field
- Bite mark comparison
Common questions
What limits the reliability of transparent overlay comparison?+
Skin distorts under bite pressure and heals or changes over time, so a match in shape does not carry the same certainty as a fixed, rigid-surface impression, and courts have increasingly scrutinised bite mark comparison methods on this basis.
How is a transparent overlay generated in practice?+
The suspect's dental cast is photographed or scanned, the biting edges are traced or digitally extracted at true life size, and that outline is printed onto a transparent sheet for direct visual superimposition over the bite mark photograph.
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