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WHO / PSR probe (ball-tip probe)

Also called: WHO probe, PSR probe, CPITN probe, ball-end probe

A screening probe with a tiny ball tip and a dark band from 3.5 to 5.5 mm.

This probe is used for PSR (Periodontal Screening and Recording), a quick gum-health check that gives each sextant (sixth of the mouth) a code from 0 to 4. It has a 0.5 mm ball on the end, which is gentler and helps feel rough calculus. A colored band runs from 3.5 to 5.5 mm; how much of that band stays visible tells you the score.

How to spot it

  • A small ball, about the size of a pinhead, on the very tip.
  • One colored band between 3.5 and 5.5 mm from the tip (some add more marks).
  • Probe vs. explorer: the ball end is blunt; explorers are sharp.

What it is used for

  • Quick screening at check-ups; the highest score in each sextant is recorded.
  • Band fully visible = healthy-range score; band partly hidden = moderate pocket; band disappears = deep pocket.

Safety and care

  • Critical item (it goes into soft tissue or touches bone): clean it, package it and heat-sterilize it after every patient.

Related

Sources: Dentalcare.com CE617. Periodontal Screening and Recording: Its Use When Detecting Periodontal Disease, Ergodenta. Periodontal Probes Guide: UNC-15, Williams, WHO, Naber's & CPITN. ; UNC-15 product listing