Skin Distortion
Definition
The deformation of a bite mark pattern caused by the viscoelastic properties of skin, body position, postmortem change, and healing. PCAST identified skin distortion as one of the two fundamental scientific problems (the other being the unknown uniqueness of dentition) that bite mark analysis has not resolved.
- Contributing factors
- Skin viscoelasticity, body position, postmortem change, healing
- Flagged by
- PCAST report as an unresolved scientific problem
- Companion problem
- Unknown uniqueness of human dentition
Common questions
Why does skin distortion undermine bite mark comparisons?+
Because the same dentition can produce differently shaped marks on skin depending on position, pressure, and tissue changes after death, an examiner cannot reliably tell whether an apparent match or mismatch reflects the true source.
Has a method been validated to correct for skin distortion?+
No, there is no accepted, validated technique to reliably reverse or quantify the distortion so that a bite mark pattern can be compared to dentition with confidence.
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