15.3 Periodontal Examination & Diagnosis
Key Takeaways
A complete periodontal exam records probing depths, CAL/recession, BOP, plaque/calculus, furcation (Glickman), mobility (Miller), mucogingival relationships, occlusion, and appropriate radiographs—then integrates findings into a 2017 diagnosis.
Probe with a calibrated instrument, walking stroke, ~0.25 N (light) force; six sites per tooth is standard; bleeding on probing indicates inflammation of the pocket/sulcus wall but can be reduced in smokers.
Miller mobility: Class I <1 mm horizontal; Class II ≥1 mm horizontal without vertical; Class III vertical depression and/or severe horizontal mobility.
Glickman furcation: I incipient, II cul-de-sac, III through-and-through, IV through-and-through with gingival recession exposing the furcation.
Radiographs underestimate three-dimensional defects; use bitewings/periapicals (and CBCT only when justified) to assess crestal bone, calculus, overhangs, furcation radiolucency, and endodontic status—always correlate with clinical CAL.
15.3 Periodontal Examination & Diagnosis
Quick Answer: Chart six sites/tooth: PD, recession/CAL, BOP, furcation, mobility, plaque. Add mucogingival assessment, occlusion, and radiographs. Use Miller for mobility and Glickman for furcation. Interpret bone levels relative to CEJ, then assign 2017 stage/grade. Never diagnose bone loss from a single dark bitewing artifact without clinical correlation.
Examination converts pathogenesis theory into a treatment plan. AFK stems often give partial chart data—practice translating numbers into disease vs health and into Stage/Grade hypotheses.
Components of a Complete Periodontal Examination
| Component | What you record | Why it matters |
|---|---|---|
| Medical/dental history | Diabetes, smoking, meds (CCB, phenytoin, cyclosporine), prior perio therapy, hygiene habits | Grade modifiers + etiology |
| Extra-/intraoral soft tissue | Nodes, mucosal disease, abscess tracks | Systemic and acute conditions |
| Plaque and calculus | Indices or descriptive scores; supra- vs subgingival calculus | Etiologic load, oral hygiene baseline |
| Gingival description | Color, contour, consistency, recession, enlargements | Inflammation vs fibrosis vs drug overgrowth |
| Probing depth | 6 sites per tooth (MB, B, DB, ML, L, DL) | Pocketing, hygiene access |
| CAL / recession | CEJ reference | Staging severity |
| BOP / suppuration | Presence after probing | Inflammatory activity |
| Furcation | Glickman I–IV | Complexity → stage upgrade |
| Mobility | Miller I–III | Support loss, trauma, acute processes |
| Mucogingival | Keratinized tissue width, frena, MGJ | Recession risk, graft decisions |
| Occlusion | Fremitus, wear, interferences, drifting | Secondary occlusal trauma |
| Radiographs | Crest, defects, furcation, calculus, caries, endo | Hard-tissue complement to CAL |
| Vitality when needed | Cold/EPT | Endo–perio differential |
Probing Technique
Instrument and force
Use a calibrated periodontal probe (Williams, UNC-15, WHO/CPITN probe depending on screening vs full chart). Insert parallel to the long axis; angulate slightly under contacts for interproximal col. Walking stroke: short steps around the circumference, recording the deepest reading in each of six zones.
| Parameter | Practical target |
|---|---|
| Force | Approximately 0.25 N (~25 g)—light; heavy force falsely deepens readings and traumatizes tissue |
| Angulation | Parallel to root; avoid over-angulation that skips into soft tissue |
| Sites | Six per tooth standard for full exam |
| Inflamed tissue | Probe tip may penetrate JE more easily → slightly deeper readings |
| Implants | Plastic or careful metal probing per protocol; baseline after prosthesis |
Screening vs comprehensive exam: indices such as CPITN/PSR (Periodontal Screening and Recording) use a WHO ball-end probe and coded sextants for screening. Codes that suggest pockets or calculus trigger a full periodontal chart. AFK expects you to know that screening is not a substitute for full charting once disease is suspected.
PSR/CPITN-style code awareness (screening)
| Code (typical PSR) | Meaning (concept) |
|---|---|
| 0 | Colored band fully visible; no calculus/overhangs; no BOP |
| 1 | Band visible; BOP |
| 2 | Band visible; calculus or defective margins |
| 3 | Band partly visible → moderate pocket zone |
| 4 | Band not visible → deep pocket zone |
| * | Furcation, mobility, mucogingival problem, or recession flagged |
Clinical Attachment Level: Calculation Drill
| Gingival margin position | Formula |
|---|---|
| Margin at CEJ | CAL = PD |
| Margin apical to CEJ (recession) | CAL = PD + recession |
| Margin coronal to CEJ (enlargement) | CAL = PD − (margin to CEJ distance) |
Example A: PD 4 mm, recession 2 mm → CAL = 6 mm.
Example B: PD 6 mm, margin 2 mm coronal to CEJ, no true attachment loss → CAL = 4 mm (or less if JE still near CEJ)—illustrates pseudopocket risk.
Example C: PD 3 mm, recession 4 mm → CAL = 7 mm (attachment loss with shallow residual pocket after recession).
AFK trap: shallow pockets do not equal health if recession + CAL is severe (burned-out or treated sites, or progressive recession disease).
Bleeding on Probing (BOP)
BOP is a sign of sulcular/pocket wall inflammation. It is more sensitive for inflammation than color alone. Absence of BOP is a strong negative predictor of future attachment loss at a site (stable). Presence of BOP, especially repeated over visits, raises risk but is not proof of inevitable progression at every site.
| Modifier | Effect on BOP |
|---|---|
| Smoking | Vasoconstriction → less BOP despite disease—do not be fooled by “pink, non-bleeding” smoker tissues |
| Anticoagulants | May increase bleeding tendency |
| Heavy force probing | False-positive bleeding |
| Recent hygiene improvement | BOP may lag days–weeks behind plaque reduction |
Suppuration on probing or digital pressure suggests a high neutrophil exudate load—mark sites and reevaluate for abscess or uncontrolled activity.
Plaque and Calculus Assessment
Simple ordinal indices (e.g., Silness–Löe plaque index concepts, presence/absence charts) document hygiene. Note plaque-retentive factors: overhanging restorations, open contacts with food impaction, calculus bridges, crowded lower anteriors, ill-fitting RPDs, unfinished crown margins.
Subgingival calculus is often dark and tenacious on root surfaces; radiographs may show proximal spurs but miss much lingual/facial calculus—clinical exploration with an explorer remains essential.
Mobility: Miller Classification
Assess with two rigid instruments (not fingers alone) using gentle buccolingual force; also check vertical depressibility.
| Miller class | Definition |
|---|---|
| Class I | First distinguishable sign of movement greater than normal; <1 mm horizontal |
| Class II | Horizontal mobility ≥1 mm; no vertical depression |
| Class III | Severe horizontal mobility and/or vertical depression into the socket |
Causes of mobility: loss of bony support, widened PDL from occlusal trauma, acute periodontal or periapical abscess (reversible component after drainage), root fracture, recent trauma/orthodontics, pregnancy-related PDL looseness (mild). Record fremitus (palpable vibration on closing) as a clinical sign of occlusal load.
Primary occlusal trauma: injury from excessive force on a tooth with normal support. Secondary occlusal trauma: normal or excessive force on a tooth with reduced support. Neither replaces biofilm control, but secondary trauma is common in advanced periodontitis (Stage III/IV complexity).
Furcation: Glickman Classification
Use a curved furcation probe (Nabers) for molars (and maxillary first premolars when bifurcated).
| Glickman grade | Clinical meaning |
|---|---|
| I | Incipient — pocket into flute; interradicular bone largely intact; probe feels a catch |
| II | Cul-de-sac — probe enters furcation but not through-and-through |
| III | Through-and-through destruction; furcation occluded by gingiva clinically |
| IV | Through-and-through with gingival recession so furcation is clinically visible |
Anatomy reminders: mandibular molars — buccal and lingual furcation entrances; maxillary molars — buccal, mesial, distal (mesial often approached from palate). Enamel projections and root concavities complicate debridement. Furcation II/III is a Stage III complexity factor in 2017 staging.
Mucogingival Examination
| Parameter | Clinical question |
|---|---|
| Recession depth | CEJ to free gingival margin |
| Recession width | Mesiodistal at widest |
| Keratinized tissue width | Free gingival margin to MGJ |
| Attached gingiva | Keratinized tissue minus probing depth |
| Frenal pull | Blanching/recession at midline or buccal frena |
| Phenotype | Thin scalloped vs thick flat—thin biotype risks recession |
Miller’s recession classification (Class I–IV) for mucogingival surgery predictability is still taught: involvement of MGJ and interdental bone/soft tissue determines graft prognosis. Do not confuse Miller recession classes with Miller mobility classes.
Radiographic Examination in Periodontics
What radiographs show well
| Finding | Interpretation notes |
|---|---|
| Crestal height / CEJ–crest distance | >2 mm suggests bone loss when technique is correct |
| Horizontal vs vertical patterns | Parallel crest vs angular defects |
| Furcation arrows / radiolucency | Especially mandibular molars; maxillary furcations harder |
| Widened PDL space | Trauma, mobility, osteitis, early disease |
| Calculus spurs | Proximal radiopaque juts |
| Overhangs / open margins | Local risk factors |
| Periapical status | Endo–perio links; root length for CAL% estimates |
| Root geometry | Length, dilaceration, residual bone support % |
Limitations
- 2D images underestimate bone loss and miss facial/lingual cortical defects.
- Technique errors (angulation, overlapping contacts) mimic or hide crestal loss.
- Early attachment loss may not be radiographically evident—CAL rules.
- CBCT for routine perio charting is not first-line; reserve for selected surgical/implant questions.
Film selection: vertical bitewings improve crest visualization in moderate–severe bone loss; periapicals show full root for percent bone loss and endodontic status; panoramic is overview only—insufficient alone for fine crestal diagnosis.
Integrating Findings into Diagnosis
Decision sequence (AFK-friendly)
- Is inflammation present? (BOP, erythema, edema)
- Is there attachment/bone loss consistent with periodontitis? (CAL pattern, RBL)
- If no CAL pattern → gingivitis or health (with or without reduced periodontium).
- If periodontitis case → stage (severity + complexity) + grade (%RBL/age, smoking, diabetes, longitudinal data) + extent.
- Add site-specific notes: abscess, endo–perio, furcation, mucogingival, occlusal trauma.
- Assign risk level for maintenance interval planning (therapy chapter).
Risk factor checklist to document every exam
| Risk factor | Document |
|---|---|
| Tobacco | Type, amount/day, years |
| Diabetes | Diagnosis, latest HbA1c if known |
| Oral hygiene / plaque score | Baseline and trends |
| Prior periodontitis / tooth loss reason | Critical for staging |
| Local factors | Overhangs, calculus, crowding |
| Compliance history | Predicts grade behavior practically |
| Family early tooth loss | Possible high susceptibility |
Acute presentations not to miss
| Presentation | Keys |
|---|---|
| Periodontal abscess | Vital tooth often; localized swelling; deep pocket; lateral radiolucency possible; drainage through pocket |
| Endodontic abscess | Non-vital; apical radiolucency; sinus tract may probe to apex |
| Necrotizing disease | Pain, necrosis, fetor—urgent hygiene/debridement pathway |
| Pericoronitis | Partially erupted third molar soft tissue—not chronic periodontitis staging |
Sample chart interpretation
Patient: 55 years, HbA1c 8.1%, non-smoker. Generalized PD 5–8 mm, interdental CAL 5–7 mm, RBL to middle third, three molars with Glickman II, four teeth lost to periodontitis historically, generalized BOP 40%.
→ Generalized periodontitis, Stage III, Grade C (indirect %RBL/age likely >1 and diabetes HbA1c ≥7%). Unstable; needs cause-related therapy (Chapter 16).
Rapid review list
- Full exam = PD + CAL + BOP + furcation + mobility + MG + radiographs + risks
- Six sites/tooth; light probing force ~0.25 N
- CAL = f(PD, margin vs CEJ)
- Smokers may not bleed—still probe carefully
- Miller mobility I / II / III
- Glickman furcation I–IV
- Radiographs complement, never replace, clinical attachment data
- Diagnosis language: 2017 stage + grade + extent
Chapter 16 applies these diagnoses to nonsurgical therapy, surgery basics, and periodontal–systemic links.
A site has a probing depth of 5 mm and 2 mm of recession (gingival margin apical to the CEJ). What is the clinical attachment loss at that site?
7 mm
3 mm
5 mm
2 mm
Which description matches Miller Class II tooth mobility?
No movement beyond normal physiologic mobility
Horizontal mobility ≥1 mm without vertical depressibility
Vertical depression into the socket as the defining feature alone for Class II
Mobility only detectable with radiography, not clinically
Glickman Grade III furcation involvement means:
Incipient catch into the furcation flute only
Through-and-through destruction with gingival recession making the furcation clearly visible
Through-and-through interradicular destruction that is not clinically visible because soft tissue still covers the furcation
No bone loss in the furcation area
Why can a heavy smoker with significant attachment loss show relatively little bleeding on probing?
Smoking permanently sterilizes the mouth so periodontitis is impossible
BOP only occurs on primary teeth
Probing is contraindicated in all smokers so BOP cannot be measured
Nicotine-related vasoconstriction and altered inflammation can reduce BOP and mask clinical inflammation
Sections you finish are checked off in the contents.