Diagnosis & Pulp Classification
Comprehensive reference for endodontic pulp and periapical diagnosis. Covers the AAE diagnostic classification, pulp testing methods, and clinical decision-making for treatment planning. This content is intended as an educational guide — clinical judgment and individual patient assessment remain paramount.
Last updated: 26 Apr 2026
Chairside Decision Support
Golden Tips
Short clinical rules for the moment when symptoms, tests, and images are not lining up cleanly.
Main rule
If the pain and clinical findings do not match, do not start treatment.
Situation
Patient has pain and points to a tooth
Treat only when history, tests, radiograph, and complaint all point to the same tooth.
Situation
Patient has pain and points to a tooth
Treat only when history, tests, radiograph, and complaint all point to the same tooth.
- Start with provisional pulp and apical diagnoses.
- Use control teeth for all tests.
- Repeat testing when findings conflict.
- Do not start RCT from a radiograph alone.
- Do not trust one cold test by itself.
- Complaint and findings still do not match.
- The causative tooth is not clear.
Situation
Patient describes the problem in their own words
Write the complaint before testing, because the obvious tooth may not be the painful tooth.
Situation
Patient describes the problem in their own words
Write the complaint before testing, because the obvious tooth may not be the painful tooth.
- Record the first site and the current site.
- Ask whether the pain has moved.
- Let the history guide which tests matter most.
- Do not let caries, a restoration, or a radiolucency hijack the diagnosis.
- The story suggests sinus, muscle, neuralgic, or medical pain.
Situation
You are taking the pain history
Lock down five things before testing: location, onset, intensity, trigger/relief, and duration.
Situation
You are taking the pain history
Lock down five things before testing: location, onset, intensity, trigger/relief, and duration.
- Ask where it started and where it is now.
- Ask what provokes and what relieves it.
- Ask whether it stops in seconds or lingers for minutes.
- Do not lead with only yes/no cold-pain questions.
- The history is vague and dental tests cannot reproduce it.
Situation
Patient took medication before the appointment
Ask what analgesic or anti-inflammatory they took; it can distort the pain story and test response. Record recent antibiotics separately because they can change the infection history.
Situation
Patient took medication before the appointment
Ask what analgesic or anti-inflammatory they took; it can distort the pain story and test response. Record recent antibiotics separately because they can change the infection history.
- Record analgesics or anti-inflammatories taken in the last 4-6 hours.
- Record any recent antibiotics separately.
- Treat heavy analgesic use as a severity clue.
- Retest later if the case is not urgent and results are unclear.
- Do not call a tooth normal just because testing is muted.
- Systemic signs or medical risk changes the safety of care.
Situation
History suggests pulpitis
Cold can be considered the primary sensibility test; compare response and duration with control teeth.
Situation
History suggests pulpitis
Cold can be considered the primary sensibility test; compare response and duration with control teeth.
- Test adjacent and contralateral controls first.
- Record whether cold reproduces the complaint.
- Record duration, not just response/no response.
- Do not treat heat as the default pulp-screening test.
- Do not ignore the control-tooth comparison.
- The chief complaint cannot be reproduced or confirmed.
Situation
Cold test causes pain
Quickly resolving cold pain leans reversible; lingering or spontaneous pain that matches the complaint leans symptomatic irreversible pulpitis.
Situation
Cold test causes pain
Quickly resolving cold pain leans reversible; lingering or spontaneous pain that matches the complaint leans symptomatic irreversible pulpitis.
- Compare with control teeth.
- Record seconds or minutes.
- Look for the cause: caries, defective restoration, recent procedure, crack, or exposure.
- Do not label irreversible pulpitis from mild cold pain alone.
- Symptoms are severe but no tooth can be identified.
Situation
You are interpreting cold, heat, or EPT
Cold, heat, and EPT are sensibility tests; they show nerve response, not true pulp blood supply.
Situation
You are interpreting cold, heat, or EPT
Cold, heat, and EPT are sensibility tests; they show nerve response, not true pulp blood supply.
- Say responds or does not respond.
- Interpret response quality and duration with the radiograph.
- Use AAE diagnostic categories.
- Do not diagnose pulp health from EPT alone.
- Test results contradict the history, radiograph, or exam.
Situation
Tooth does not respond to cold or EPT
No response suggests necrosis, but calcification, previous endodontic treatment, trauma, crowns, and altered anatomy can mislead.
Situation
Tooth does not respond to cold or EPT
No response suggests necrosis, but calcification, previous endodontic treatment, trauma, crowns, and altered anatomy can mislead.
- Check the periapical radiograph first.
- Look for calcification, root filling, pulpotomy history, trauma, or immature apex.
- Retest with another method when the finding is unexpected.
- Do not treat a calcified tooth only because it does not respond.
- A calcified tooth has no symptoms and no apical change.
Situation
Patient has biting pain or percussion tenderness
Percussion and palpation locate PDL or periradicular inflammation; they do not tell you pulp status.
Situation
Patient has biting pain or percussion tenderness
Percussion and palpation locate PDL or periradicular inflammation; they do not tell you pulp status.
- Percuss control teeth first.
- Record normal, tender, very tender, or different.
- Palpate for swelling, expansion, and side-to-side differences.
- Do not use percussion as a pulp vitality test.
- Tenderness exists but pulp and radiographic findings do not support an endodontic source.
Situation
You see a sinus tract
Trace the sinus tract before choosing the causative tooth; the opening may be distant from the source.
Situation
You see a sinus tract
Trace the sinus tract before choosing the causative tooth; the opening may be distant from the source.
- Use a gutta-percha point and periapical radiograph.
- Check narrow isolated defects for vertical root fracture or developmental groove.
- Expect chronic apical abscess to drain with little pain.
- Do not assume the nearest tooth is the source.
- The tract does not trace to a dental source or does not heal after treatment.
Situation
Radiograph looks suspicious or symptoms are confusing
A periapical radiograph is essential, but clinical correlation decides the diagnosis.
Situation
Radiograph looks suspicious or symptoms are confusing
A periapical radiograph is essential, but clinical correlation decides the diagnosis.
- Compare with older radiographs.
- Use different angulations when anatomy is unclear.
- Use bitewings or panoramic images only as adjuncts.
- Do not diagnose endodontic disease from a 2D image alone.
- Imaging and pulp-test results disagree.
Situation
Radiolucency or swelling does not fit a routine pulpal source
Multilocular, multifocal, rapidly expanding, moth-eaten, perforating, or root-resorbing lesions are not routine endodontic lesions until proven otherwise.
Situation
Radiolucency or swelling does not fit a routine pulpal source
Multilocular, multifocal, rapidly expanding, moth-eaten, perforating, or root-resorbing lesions are not routine endodontic lesions until proven otherwise.
- Check whether involved teeth respond normally.
- Look for expansion, perforation, mobility, irregular resorption, or mixed opacity.
- Arrange biopsy, radiology, oral medicine, oral surgery, or medical referral.
- Do not use RCT as a diagnostic biopsy substitute.
- The lesion pattern is destructive or inconsistent with pulp necrosis.
Situation
Toothache-like pain but dental findings do not explain it
If dental tests cannot reproduce or explain the pain, think nonodontogenic before drilling.
Situation
Toothache-like pain but dental findings do not explain it
If dental tests cannot reproduce or explain the pain, think nonodontogenic before drilling.
- Screen for muscle, sinus, neuralgic, headache-type, and medical patterns.
- Use anesthesia response cautiously.
- Refer when the source is not dental.
- Do not perform irreversible dental treatment for pain you cannot localize.
- Pain persists despite anesthesia, or muscle/sinus/neuralgic features dominate.
1. Pulp Diagnosis Categories
Current Standard — AAE 2009 Classification
01Normal PulpAsymptomatic, normal response to sensibility testing, no radiographic changes
Key Features
Asymptomatic, normal response to sensibility testing, no radiographic changes
Treatment Direction
No endodontic treatment indicated
02Reversible PulpitisSharp, transient pain to thermal stimuli; pain resolves quickly after stimulus removal
Key Features
Sharp, transient pain to thermal stimuli; pain resolves quickly after stimulus removal
Treatment Direction
Address cause (caries, restoration); pulp may recover
03Symptomatic Irreversible PulpitisSpontaneous, lingering pain (often >30 s after thermal); may be positional; sleep-disturbing
Key Features
Spontaneous, lingering pain (often >30 s after thermal); may be positional; sleep-disturbing
Treatment Direction
RCT or vital pulp therapy may be considered
04Asymptomatic Irreversible PulpitisNo symptoms; exposure from caries/trauma; pulp unlikely to recover
Key Features
No symptoms; exposure from caries/trauma; pulp unlikely to recover
Treatment Direction
RCT or vital pulp therapy may be considered
05Pulp NecrosisNo response to sensibility testing; may have discoloration
Key Features
No response to sensibility testing; may have discoloration
Treatment Direction
Consider RCT after clinical and radiographic correlation
06Previously TreatedEndodontically treated tooth
Key Features
Endodontically treated tooth
Treatment Direction
Evaluate for retreatment if periapical pathology present
07Previously Initiated TherapyTreatment started but not completed
Key Features
Treatment started but not completed
Treatment Direction
Complete treatment based on clinical assessment
| Category | Key Features | Treatment Direction |
|---|---|---|
| Normal Pulp | Asymptomatic, normal response to sensibility testing, no radiographic changes | No endodontic treatment indicated |
| Reversible Pulpitis | Sharp, transient pain to thermal stimuli; pain resolves quickly after stimulus removal | Address cause (caries, restoration); pulp may recover |
| Symptomatic Irreversible Pulpitis | Spontaneous, lingering pain (often >30 s after thermal); may be positional; sleep-disturbing | RCT or vital pulp therapy may be considered |
| Asymptomatic Irreversible Pulpitis | No symptoms; exposure from caries/trauma; pulp unlikely to recover | RCT or vital pulp therapy may be considered |
| Pulp Necrosis | No response to sensibility testing; may have discoloration | Consider RCT after clinical and radiographic correlation |
| Previously Treated | Endodontically treated tooth | Evaluate for retreatment if periapical pathology present |
| Previously Initiated Therapy | Treatment started but not completed | Complete treatment based on clinical assessment |
Emerging Update: AAE + ESE 2025 Draft Revision
A joint AAE and ESE committee has proposed replacing the binary reversible/irreversible classification with a severity gradient: Mild Pulpitis and Severe Pulpitis. This framework may better support vital pulp therapy decisions. Additional proposed categories include Hypersensitive Pulp and Inconclusive Pulp Status. The proposal also updates necrosis and prior-treatment terminology. It remains a stakeholder consultation draft and has not been formally adopted.
2. Periapical Diagnosis Categories
AAE 2009 Classification
01Normal Apical TissuesNo symptoms on percussion/palpation; intact lamina dura; uniform PDL space
Key Features
No symptoms on percussion/palpation; intact lamina dura; uniform PDL space
Clinical Significance
No periapical pathology
02Symptomatic Apical PeriodontitisPain on biting/percussion; may have localized swelling; radiolucency may or may not be present
Key Features
Pain on biting/percussion; may have localized swelling; radiolucency may or may not be present
Clinical Significance
Suggests pulpal pathology extending to periapex
03Asymptomatic Apical PeriodontitisNo symptoms; radiolucency present at apex
Key Features
No symptoms; radiolucency present at apex
Clinical Significance
Suggests chronic pulpal pathology
04Acute Apical AbscessRapid onset; pain, swelling, purulence; may have systemic signs (fever, lymphadenopathy)
Key Features
Rapid onset; pain, swelling, purulence; may have systemic signs (fever, lymphadenopathy)
Clinical Significance
Urgent care: drainage and endodontic source control; antibiotics if systemic
05Chronic Apical AbscessIntermittent drainage via sinus tract; minimal discomfort; radiolucency present
Key Features
Intermittent drainage via sinus tract; minimal discomfort; radiolucency present
Clinical Significance
Endodontic treatment is indicated; trace sinus tract with GP cone
06Condensing OsteitisDiffuse radiopaque area at apex; associated with a vital or necrotic pulp
Key Features
Diffuse radiopaque area at apex; associated with a vital or necrotic pulp
Clinical Significance
May resolve after treatment of the associated tooth
| Category | Key Features | Clinical Significance |
|---|---|---|
| Normal Apical Tissues | No symptoms on percussion/palpation; intact lamina dura; uniform PDL space | No periapical pathology |
| Symptomatic Apical Periodontitis | Pain on biting/percussion; may have localized swelling; radiolucency may or may not be present | Suggests pulpal pathology extending to periapex |
| Asymptomatic Apical Periodontitis | No symptoms; radiolucency present at apex | Suggests chronic pulpal pathology |
| Acute Apical Abscess | Rapid onset; pain, swelling, purulence; may have systemic signs (fever, lymphadenopathy) | Urgent care: drainage and endodontic source control; antibiotics if systemic |
| Chronic Apical Abscess | Intermittent drainage via sinus tract; minimal discomfort; radiolucency present | Endodontic treatment is indicated; trace sinus tract with GP cone |
| Condensing Osteitis | Diffuse radiopaque area at apex; associated with a vital or necrotic pulp | May resolve after treatment of the associated tooth |
3. Pulp Testing Methods
Sensibility tests
Measures
Neural response
Does not measure
Blood flow
Primary sensibility option
Cold Test
Apply CO₂ snow, Endo-Ice, or refrigerant spray to the tooth. Use adjacent and contralateral teeth as controls before interpreting the response.
Response pattern
Normal
Brief sharp response that resolves quickly
Lingering
Prolonged or spreading pain may suggest irreversible pulpitis
No response
May suggest necrosis, but restorations, calcification, trauma, and crowns can mislead
Compare first
A single tooth response is weaker than a pattern. Compare with adjacent and contralateral teeth before committing to a diagnosis.
Adjunct tests
02Electric Pulp Test (EPT)
Threshold data when cold response is equivocal.
Electric Pulp Test (EPT)
Threshold data when cold response is equivocal.
When
Use as a supplementary test after cold testing, especially when the cold response is unclear.
Read
It indicates neural response threshold, not disease severity. Multi-rooted teeth with partial necrosis may give misleading positives.
03Heat Test
Useful when the patient reports heat-triggered symptoms.
Heat Test
Useful when the patient reports heat-triggered symptoms.
When
Use heated gutta-percha or warm water when heat reproduces the chief complaint.
Read
Lingering pain after heat may support irreversible pulpitis when the rest of the findings agree.
04Percussion & Palpation
Reads the periapical ligament and apical tissues.
Percussion & Palpation
Reads the periapical ligament and apical tissues.
When
Use with pulp tests to separate pulpal status from periapical involvement.
Read
Percussion sensitivity may suggest apical periodontitis; palpation tenderness over the apex may indicate periapical inflammation.
05Selective Anesthesia
Localization aid for referred or poorly localized pain.
Selective Anesthesia
Localization aid for referred or poorly localized pain.
When
Use when the pain story points to a region but the source tooth remains uncertain.
Read
Resolution of symptoms after targeted anesthesia supports the anesthetized tooth or region as the source.
06Bite Test / Tooth Slooth
Cusp-by-cusp loading for suspected cracks.
Bite Test / Tooth Slooth
Cusp-by-cusp loading for suspected cracks.
When
Use when biting or release pain is part of the complaint, especially with cracked-tooth suspicion.
Read
Selective cusp loading that reproduces the symptom may help localize an incomplete fracture.
Sensibility is not vitality
Sensibility
Cold and EPT assess nerve response. Most chairside pulp tests are in this category.
Vitality
LDF and pulse oximetry assess blood flow directly, but they are not standard tests in most routine endodontic diagnostic workflows.
4. Clinical Decision Tree
Symptoms + Test Results → Diagnosis → Treatment Direction
01Cold TestNormalEPTNormalPercussionNormalNo symptoms; routine findingNormal Pulp
Cold Test
Normal
EPT
Normal
Percussion
Normal
Likely Diagnosis
Normal Pulp
Treatment Direction
No treatment
02Cold TestNormal/exaggeratedEPTNormalPercussionNormalBrief sensitivity to cold/sweetReversible Pulpitis
Cold Test
Normal/exaggerated
EPT
Normal
Percussion
Normal
Likely Diagnosis
Reversible Pulpitis
Treatment Direction
Address etiology; monitor
03Cold TestExaggerated/lingeringEPTVariablePercussionMay be tenderSpontaneous/lingering painIrreversible Pulpitis
Cold Test
Exaggerated/lingering
EPT
Variable
Percussion
May be tender
Likely Diagnosis
Irreversible Pulpitis
Treatment Direction
RCT or VPT may be considered
04Cold TestMay respondEPTMay respondPercussionNormalNo symptoms; deep caries/exposureAsymptomatic Irreversible Pulpitis
Cold Test
May respond
EPT
May respond
Percussion
Normal
Likely Diagnosis
Asymptomatic Irreversible Pulpitis
Treatment Direction
RCT or VPT may be considered
05Cold TestNo responseEPTNo responsePercussionMay be tenderNo response; discolorationPulp Necrosis
Cold Test
No response
EPT
No response
Percussion
May be tender
Likely Diagnosis
Pulp Necrosis
Treatment Direction
Consider RCT after clinical/radiographic correlation
06Cold TestVariableEPTVariablePercussionTender/painfulPain on biting; periapical radiolucencyApical Periodontitis
Cold Test
Variable
EPT
Variable
Percussion
Tender/painful
Likely Diagnosis
Apical Periodontitis
Treatment Direction
Consider RCT once endodontic source is confirmed
07Cold TestNo responseEPTNo responsePercussionTender/painfulSwelling, fever, purulenceAcute Apical Abscess
Cold Test
No response
EPT
No response
Percussion
Tender/painful
Likely Diagnosis
Acute Apical Abscess
Treatment Direction
Urgent: drainage and endodontic treatment; antibiotics for systemic signs
08Cold TestNo responseEPTNo responsePercussionMild/noneSinus tract presentChronic Apical Abscess
Cold Test
No response
EPT
No response
Percussion
Mild/none
Likely Diagnosis
Chronic Apical Abscess
Treatment Direction
Endodontic treatment is indicated
| Clinical Presentation | Cold Test | EPT | Percussion | Likely Diagnosis | Treatment Direction |
|---|---|---|---|---|---|
| No symptoms; routine finding | Normal | Normal | Normal | Normal Pulp | No treatment |
| Brief sensitivity to cold/sweet | Normal/exaggerated | Normal | Normal | Reversible Pulpitis | Address etiology; monitor |
| Spontaneous/lingering pain | Exaggerated/lingering | Variable | May be tender | Irreversible Pulpitis | RCT or VPT may be considered |
| No symptoms; deep caries/exposure | May respond | May respond | Normal | Asymptomatic Irreversible Pulpitis | RCT or VPT may be considered |
| No response; discoloration | No response | No response | May be tender | Pulp Necrosis | Consider RCT after clinical/radiographic correlation |
| Pain on biting; periapical radiolucency | Variable | Variable | Tender/painful | Apical Periodontitis | Consider RCT once endodontic source is confirmed |
| Swelling, fever, purulence | No response | No response | Tender/painful | Acute Apical Abscess | Urgent: drainage and endodontic treatment; antibiotics for systemic signs |
| Sinus tract present | No response | No response | Mild/none | Chronic Apical Abscess | Endodontic treatment is indicated |
This table provides general guidance. Individual cases may present atypically. Combining multiple test results with clinical and radiographic findings generally leads to more reliable diagnoses.
5. Frequently Asked Questions
01What is the difference between sensibility and vitality testing?
What is the difference between sensibility and vitality testing?
Short answer
Sensibility tests (cold, EPT) assess neural response.
- 01Vitality tests (LDF, pulse oximetry) assess blood flow.
- 02Most clinical tests are sensibility-based.
- 03A tooth with compromised blood supply but intact nerves may still respond to sensibility testing, and vice versa.
- 04LDF and pulse oximetry are not routine diagnostic tests in most clinical workflows.
02Can a tooth diagnosed with irreversible pulpitis receive vital pulp therapy?
Can a tooth diagnosed with irreversible pulpitis receive vital pulp therapy?
Short answer
According to the AAE 2021 position statement, a pretreatment diagnosis of irreversible pulpitis is not necessarily an indication for pulpectomy.
- 01The ESE S3 CPG (2023) suggests that for teeth with spontaneous-pain pulpitis, either root canal treatment or full pulpotomy may be effective.
- 02Hemostasis during the procedure is generally considered the critical intraoperative decision point.
03When may CBCT be considered for endodontic diagnosis?
When may CBCT be considered for endodontic diagnosis?
Short answer
CBCT is not a routine screening tool.
- 01When clinical examination and conventional radiography do not meet the diagnostic need, limited FOV CBCT may be considered for contradictory or nonspecific findings, calcified canal localization, resorption, suspected vertical root fracture, surgical planning, or localized dentoalveolar trauma.
- 02The AAE and AAOMR 2025 update was published in January 2026.
References
- Levin LG, Law AS, Holland GR, Abbott PV, Roda RS. "Identify and define all diagnostic terms for pulpal health and disease states." — J Endod (2009);35(12):1645-1657. PMID 19932339
- Duncan HF, El-Karim I. "Endodontic S3-level clinical practice guidelines: the European Society of Endodontology process and recommendations." — Br Dent J (2025);238(7):580-586. PMID 40217051; PMC11991915
- Duncan HF et al. Treatment of pulpal and apical disease: The European Society of Endodontology (ESE) S3-level clinical practice guideline — Int Endod J (2023);56 Suppl 3:238-295. DOI 10.1111/iej.13974
- American Association of Endodontists. Updating Diagnostic Terminology in Endodontics — living web resource published July 2025, last updated March 2026
- Glickman GN. "AAE Consensus Conference on Diagnostic Terminology: background and perspectives." — J Endod (2009);35(12):1619-1620. PMID 19932336
- Jafarzadeh H, Abbott PV. "Review of pulp sensibility tests. Part I: general information and thermal tests" — Int Endod J (2010);43:738-762. PMID 20609022
- Jafarzadeh H, Abbott PV. "Review of pulp sensibility tests. Part II: electric pulp tests and test cavities" — Int Endod J (2010);43:945-958. PMID 20726917
- AAE and AAOMR Joint Position Statement: Use of Cone-Beam Computed Tomography in Endodontics 2025 Update — Oral Surg Oral Med Oral Pathol Oral Radiol (2026);141(1):126-135. PMID 41407481
- Mainkar A, Kim SG. "Diagnostic Accuracy of 5 Dental Pulp Tests: A Systematic Review and Meta-analysis" — J Endod (2018);44:694-702. DOI 10.1016/j.joen.2018.01.021
- International Classification of Orofacial Pain, 1st edition (ICOP) — Cephalalgia (2020);40:129-221. DOI 10.1177/0333102419893823
Disclaimer
This information is for educational purposes only. Clinical diagnosis should be based on comprehensive patient evaluation including history, examination, and appropriate testing. It should not be used as the sole basis for clinical decision-making.