Digital Superimposition
Definition
Computer-assisted alignment of two radiographic images to assess feature correspondence. Software adjusts size, rotation, and contrast to optimise overlay, and highlights matching and divergent areas.
- Input
- Two radiographic images, ante-mortem and post-mortem
- Adjustments made
- Size, rotation, and contrast
- Output
- An overlay highlighting matching and divergent regions
- Field
- Forensic odontology and radiographic identification
Common questions
What can cause a false mismatch in digital superimposition?+
Different projection angles, magnification differences between the two exposures, or post-mortem changes such as bone remodelling can shift landmarks even when the images are of the same individual, so alignment must be checked before divergence is treated as exclusionary.
Is digital superimposition used alone to confirm identity?+
No. It is one comparison method among several (charting, radiographic feature counts, restoration patterns) and the result is reported alongside the other lines of dental evidence rather than as a standalone conclusion.
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