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Marquis color-coded probe
Also called: color-coded probe, 3-6-9-12 probe, CP-12
A probe with alternating dark and light bands every 3 mm (3-6-9-12).
A color-coded probe is quick to read because it uses wide bands instead of tiny lines. The Marquis-style probe changes color every 3 mm: the bands sit between 3 and 6 mm and between 9 and 12 mm. You read the depth by which band the gumline falls in.
How to spot it
- Wide alternating bands rather than thin lines.
- Band edges at 3, 6, 9 and 12 mm.
What it is used for
- Quick pocket measurements and screening.
- Some offices prefer it for speed; others prefer 1 mm marks for detail.
Safety and care
- Critical item (it goes into soft tissue or touches bone): clean it, package it and heat-sterilize it after every patient.