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?
Which description matches Miller Class II tooth mobility?
Glickman Grade III furcation involvement means:
Why can a heavy smoker with significant attachment loss show relatively little bleeding on probing?