Periodontal Examination
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Direct answer
The Basic Periodontal Examination comes first: with the ball-ended WHO probe (0.5 mm ball, black band spanning 3.5 to 5.5 mm), each sextant is scored from 0 to 4, and any sextant scoring 4 — the black band disappearing into the pocket — or an asterisk for furcation, mobility or mucogingival problems obliges full-mouth charting. The full chart then records probing depth at six sites per tooth, recession from the cementoenamel junction, bleeding, mobility, furcation and mucogingival status, from which clinical attachment level is computed. Probing force stays around 0.25 newtons (25 grams), the border of displacing healthy junctional epithelium.
What you must remember
- BPE codes: 0 healthy, 1 bleeding on probing only, 2 calculus or defective margins felt, 3 black band partially visible (pocket 3.5–5.5 mm), 4 black band fully invisible (5.5 mm or more); asterisk flags furcation, mobility, recession or mucogingival problems.
- Screen with the WHO CPTIN probe; chart with a calibrated periodontal probe such as the UNC-15 or Marquis, using about 25 grams of force — the weight that blanches a fingernail for a few seconds.
- Six sites per tooth: mesiobuccal, midbuccal, distobuccal and the mirror-image lingual sites; walk the probe in 1 mm steps around the tooth rather than stabbing once per site; healthy probing depth is 1–3 mm, and clinical gingival health is defined by bleeding at fewer than 10 per cent of sites.
- Clinical attachment level = probing depth + recession from the cementoenamel junction; a 6 mm pocket with 2 mm recession is 8 mm of attachment loss, and this is the figure the 2017 staging uses.
- Mobility (Miller): grade 0 physiologic, grade 1 up to 1 mm horizontally, grade 2 more than 1 mm horizontally, grade 3 horizontal plus vertical movability.
- Furcation (Glickman): grade I incipient, grade II cul-de-sac without through-and-through passage, grade III through-and-through but cordoned by gingiva, grade IV through-and-through with a visibly open dome; detect with the Nabers probe.
- Plaque record: O'Leary's plaque control record, aiming for better than 85 per cent plaque-free surfaces before active therapy is judged complete.
- Miller's recession classes I to IV predict root coverage prospects and travel with the mucogingival assessment.
One quadrant, charted properly
Take the lower right sextant that scored BPE 4 and slow down. Walk a calibrated probe from distobuccal through midbuccal to mesiobuccal at the second molar, repeat lingually, recording every reading and circling bleeding sites. Read the mesial of the first molar at 6 mm with 2 mm of recession: probing depth 6, attachment level 8, recession noted separately — three different facts from one site. Push the Nabers probe under the furcation of that molar from the buccal aspect; it drops and catches horizontally without exiting lingually, which is a Glickman grade II involvement. Test mobility against two instrument handles (grade 2 here), check the frenum for pull at the canine, and mark plaque on an O'Leary chart as a percentage of surfaces. This one quadrant now holds severity (attachment level), access (pocket depth), prognosis (furcation, mobility) and cause control (plaque score) — three minutes that justify structured charting over eyeballing.
Traps in the charting viva
The exam's favourite confusion is code 3 versus code 4 — the boundary is visibility of the black band, which spans 3.5 to 5.5 mm; partial visibility means 3, total disappearance means 4, and no one asks you to measure in tenths during screening. Next, the CAL question: in recession, the attachment level is almost always larger than the pocket depth, because recession is added — reporting CAL equal to PD in a tooth whose margin sits apical to the CEJ loses the mark. Then the instrument mix-up: the WHO probe screens, but its ball-ended tip is not meant for precise charting, and the Nabers probe exists only for furcations. Last, a single bleeding site triggers neither panic nor diagnosis — it is the percentage of bleeding sites and their persistence across visits that carries meaning.
Frequently asked questions
What does a BPE score of 4 mean?
A pocket of 5.5 mm or more, because the probe's entire black band (3.5–5.5 mm) disappears into the sulcus; it mandates full periodontal charting of that sextant.
How is clinical attachment level calculated?
Probing depth plus recession measured from the cementoenamel junction to the gingival margin; recession is added when the margin lies apical to the CEJ.
What is the diameter of the WHO probe ball and the recommended probing force?
A 0.5 mm ball, used with approximately 0.25 newtons (about 25 grams) — light enough to stop within a healthy junctional epithelium.
How is furcation involvement graded and with which instrument?
Glickman grades I to IV, probed with the curved Nabers probe; grade II is a cul-de-sac and grade III is a through-and-through defect still roofed by gingiva.
What percentage of bleeding sites defines gingival health?
Fewer than 10 per cent of sites, per the 2017 World Workshop case definitions.