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Six sites per tooth (MB, B, DB, ML, L, DL) with light force (about 0.25 N, roughly 20–25 g); walk the probe in small steps, kept parallel to the long axis and tilted slightly into the col interproximally.
Probing depth (PD): gingival margin to the base of the sulcus or pocket.
Clinical attachment level (CAL): from the CEJ to the base of the pocket. If the margin is apical to the CEJ (recession): CAL = PD + recession. If the margin is coronal to the CEJ (enlargement): CAL = PD − distance from the CEJ to the margin.
Bleeding on probing: its ABSENCE is a strong sign of stability; smokers may bleed less despite disease.
Furcation involvement
Glickman class
Finding
I
Incipient: probe feels the concavity but does not enter
II
Probe enters but does not pass through (cul-de-sac)
III
Through-and-through, but the opening is covered by soft tissue
IV
Through-and-through and clinically visible
Use a curved Nabers probe. Maxillary first molar: buccal from the buccal, mesial from the palatal, distal from the buccal or palatal. Mandibular molars: buccal and lingual. Maxillary first premolars can have a mesiodistal furcation.
Mobility (Miller index, commonly used)
Class
Finding
0
Physiologic
1
Slightly more than normal
2
Moderately more, up to about 1 mm horizontally
3
Severe: more than 1 mm horizontally and/or depressible vertically
Periodontal Screening and Recording (PSR), by sextant
Code
Finding with the color-banded probe (band 3.5–5.5 mm)
0
Band fully visible; no calculus, no bleeding, no defective margins
1
Band fully visible; bleeding
2
Band fully visible; calculus or defective margins
3
Band partly visible (deepest PD 3.5–5.5 mm): full charting of that sextant
4
Band disappears (PD over 5.5 mm): full-mouth charting
*
Furcation, mobility, mucogingival problem or recession of 3.5 mm or more
⚠️ Common traps
Calling probing depth 'attachment loss': CAL is measured from the CEJ.
Adding instead of subtracting when the margin is coronal to the CEJ.
Probing the mesial furcation of a maxillary molar from the buccal.
Assuming no bleeding in a heavy smoker means health.
Mini-quiz
Pick an answer to see right away whether it is correct and why.
PD is 4 mm and the gingival margin is 2 mm apical to the CEJ. What is the CAL?
PD is 6 mm and the gingival margin sits 2 mm coronal to the CEJ because of enlargement. What is the CAL?
A probe passes completely through a furcation but soft tissue still covers it. Glickman class?
A PSR probe's colored band disappears completely in one sextant. The code and next step are:
Which finding best predicts that a site will stay stable?
0 of 5 answered
Answer key: 1 C · 2 B · 3 A · 4 B · 5 D
Dental School Map · Original study material, written and checked by our team; always confirm clinical decisions against current guidelines.
