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Dental Abscess

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Overview

Dental Abscess

Quick Reference

Critical Alerts

  • Ludwig angina is a surgical emergency: Rapidly progressive floor of mouth infection
  • Airway compromise can develop quickly: Monitor for stridor, dysphagia, trismus
  • Immunocompromised patients need IV antibiotics: Higher risk of spread
  • Incision and drainage is definitive: Antibiotics alone may be insufficient
  • Dental referral essential: Definitive treatment is extraction or root canal
  • Deep space infections require CT and surgical consultation

Red Flags for Deep Space Infection

FindingConcern
Trismus (difficulty opening mouth)Masticator space involvement
Dysphagia, droolingAirway compromise
Neck swellingDeep space spread
Bilateral submandibular swellingLudwig angina
Fever, toxic appearanceSevere infection
Stridor, respiratory distressImpending airway obstruction

Emergency Treatments

ConditionTreatment
Localized dental abscessI&D + Oral antibiotics + Dental referral
Deep space infectionIV antibiotics + CT + Surgical consultation
Ludwig anginaSecure airway + IV antibiotics + Emergent surgical drainage
Pain managementNSAIDs + Opioids PRN

Definition

Overview

A dental abscess is a localized collection of pus arising from bacterial infection of the tooth or surrounding tissues. Most originate from dental caries, periodontal disease, or trauma. While many are manageable with antibiotics and dental referral, deep space extension (Ludwig angina, parapharyngeal abscess) can be life-threatening and requires emergent intervention.

Classification

By Location:

TypeOriginLocation
Periapical abscessTooth pulp necrosisAt root apex
Periodontal abscessGingival/periodontal pocketAlong tooth root laterally
Pericoronal abscessImpacted/erupting toothAround crown (e.g., wisdom tooth)
Vestibular abscessSpread to buccal mucosaOral vestibule

Deep Space Infections (Extensions):

SpaceRisk
SubmandibularLudwig angina if bilateral
SublingualAirway compromise
ParapharyngealAirway, carotid involvement
RetropharyngealMediastinitis
MasticatorTrismus

Epidemiology

  • Very common: Dental caries affect >90% of adults
  • ED visits: ~1% of all ED visits are for dental complaints
  • Deep space infections: Less common but life-threatening
  • Ludwig angina mortality: 5-10% with treatment; higher if delayed

Etiology

Pathogens (Polymicrobial):

CategoryOrganisms
AerobicStreptococcus viridans, Streptococcus anginosus group
AnaerobicPrevotella, Peptostreptococcus, Fusobacterium, Bacteroides
MixedMost dental infections are polymicrobial

Risk Factors:

  • Poor dental hygiene
  • Dental caries
  • Immunocompromise (diabetes, HIV)
  • Recent dental procedure
  • Trauma

Pathophysiology

Mechanism

  1. Dental caries or periodontal disease: Bacteria enter pulp or periodontal space
  2. Pulp necrosis: Dead pulp tissue becomes infected
  3. Periapical abscess: Pus collects at root apex
  4. Spread through bone: Path of least resistance to vestibule
  5. Deep space extension: If crosses mylohyoid or periosteum

Ludwig Angina Mechanism

  • Submandibular and sublingual space infection
  • Rapidly progressive cellulitis/phlegmon
  • Tongue elevation → Airway obstruction
  • Often originates from mandibular molars (>90%)

Clinical Presentation

Symptoms

SymptomDescription
Tooth painLocalized, severe, throbbing
SwellingIntraoral or facial
FeverVariable
Sensitivity to heat/coldEarly pulpitis
Sensitivity to percussionPeriapical abscess
TrismusMasticator space involvement
DysphagiaDeep space spread
Foul tastePus drainage

History

Key Questions:

Physical Examination

Oral Exam:

FindingSignificance
Fluctuant swelling at gingiva/vestibulePeriapical or periodontal abscess
Carious toothSource
Percussion tendernessPeriapical involvement
Mobile toothSevere infection
Purulent drainageAbscess rupture
Floor of mouth elevationLudwig angina

Extraoral Exam:

FindingSignificance
Facial swellingVestibular or deep space extension
Submandibular swellingSubmandibular space involvement
TrismusMasticator space
Cervical lymphadenopathyReactive
StridorAirway compromise
FeverSystemic spread

Which tooth? Duration of pain?
Common presentation.
Swelling location and progression
Common presentation.
Fever, chills
Common presentation.
Difficulty opening mouth (trismus)
Common presentation.
Difficulty swallowing or breathing
Common presentation.
Prior dental work
Common presentation.
Medical history (diabetes, immunocompromise)
Common presentation.
Allergies (penicillin)
Common presentation.
Red Flags

Deep Space Infection / Ludwig Angina

FindingConcernAction
Bilateral submandibular swellingLudwig anginaEmergent airway evaluation, IV abx, surgery
Floor of mouth elevationAirway compromiseSecure airway
Drooling, dysphagiaOral secretions not controlledAnticipate airway intervention
Stridor, voice changeImpending obstructionEmergent airway
Trismus (can't open mouth)Masticator/parapharyngeal spaceCT, surgery
Fever + toxic appearanceSevere infectionIV abx, imaging

Differential Diagnosis

Other Causes of Facial Swelling / Oral Pain

DiagnosisFeatures
Peritonsillar abscessSore throat, "hot potato" voice, uvular deviation
Ludwig anginaBilateral submandibular, floor of mouth elevation
Parapharyngeal abscessNeck swelling, trismus, systemic illness
ParotitisParotid swelling, pus from Stensen's duct
AngioedemaDiffuse swelling, no fever, may have urticaria
TMJ dysfunctionPain at TMJ, clicking, no swelling
TumorChronic, progressive mass

Diagnostic Approach

Clinical Diagnosis

  • Most dental abscesses are diagnosed clinically
  • Imaging for deep space concerns

Imaging

Panoramic Dental X-Ray (Panorex):

  • Visualizes teeth, periapical pathology
  • Often unavailable in ED

CT Neck with Contrast (Gold standard for deep spaces):

FindingSignificance
Rim-enhancing fluid collectionAbscess
Soft tissue gasNecrotizing infection
Extent of involvementSurgical planning

Laboratory Studies

TestIndication
CBCLeukocytosis, severe infection
BMPDehydration, diabetes assessment
Blood culturesSepsis, toxic patient
GlucoseDiabetic assessment

Treatment

Principles

  1. Assess for deep space infection: If present → Emergent management
  2. Pain control: NSAIDs, opioids PRN
  3. Antibiotics: Cover oral flora (aerobes + anaerobes)
  4. Incision and drainage: If fluctuant abscess
  5. Dental referral: Definitive treatment (extraction, root canal)

Pain Management

AgentDose
Ibuprofen400-600 mg PO q6-8h
Acetaminophen650-1000 mg PO q6h
Opioids (if severe)Hydrocodone, oxycodone short course

Antibiotics

Outpatient (Localized Abscess):

AgentDoseDuration
Amoxicillin500 mg TID7 days
Amoxicillin-Clavulanate875/125 mg BID7 days
Clindamycin (if PCN allergy)300 mg QID7 days
Metronidazole + Penicillin500 mg TID + 500 mg QID7 days

Inpatient (Severe/Deep Space):

AgentDose
Ampicillin-Sulbactam3 g IV q6h
Clindamycin600-900 mg IV q8h
Piperacillin-Tazobactam4.5 g IV q6h (if severe)
+ Metronidazole500 mg IV q8h (if anaerobic coverage needed)

Incision and Drainage

Intraoral I&D:

  • Fluctuant vestibular abscess
  • Local anesthesia (can be difficult with infection)
  • Incision at most fluctuant point
  • Blunt dissection to break loculations
  • Consider packing or drain

Deep Space I&D:

  • Performed by oral maxillofacial surgery or ENT
  • May require OR under general anesthesia
  • If airway compromised, consider awake fiberoptic intubation or tracheostomy

Ludwig Angina Management

StepIntervention
AirwayEarly intubation (fiberoptic preferred) or surgical airway
AntibioticsAmpicillin-Sulbactam or Clindamycin IV
SurgeryEmergent surgical drainage and debridement
ICUClose monitoring

Disposition

Discharge Criteria (Localized Abscess)

  • No signs of deep space infection
  • No airway compromise
  • Pain controlled
  • Able to tolerate oral antibiotics
  • Dental follow-up arranged

Admission Criteria

  • Deep space infection (submandibular, parapharyngeal)
  • Ludwig angina
  • Airway concern
  • Immunocompromised with severe infection
  • Unable to tolerate oral intake
  • Need for IV antibiotics or surgical drainage

Dental Referral

  • All dental abscesses need definitive dental care
  • Extraction or root canal therapy
  • Within 24-48 hours for localized abscess
  • Urgent for severe or recurrent infections

Patient Education

Condition Explanation

  • "You have an infection around your tooth that has formed a pocket of pus."
  • "We can drain it and give you antibiotics, but you will need to see a dentist for definitive treatment."
  • "If left untreated, this can spread and become very serious."

Home Care

  • Complete full course of antibiotics
  • Take pain medications as directed
  • Warm salt water rinses
  • Soft diet
  • Follow up with dentist promptly

Warning Signs to Return

  • Worsening swelling, especially under the jaw or in the neck
  • Difficulty breathing or swallowing
  • Fever not improving
  • Inability to open mouth
  • Worsening pain despite medication

Special Populations

Diabetics

  • Higher risk of severe infection and spread
  • Lower threshold for admission and IV antibiotics
  • Poor glycemic control worsens outcomes
  • Close follow-up essential

Immunocompromised

  • HIV, chemotherapy, transplant patients
  • Atypical organisms possible
  • Broader antibiotic coverage
  • Early imaging and surgical consultation

Pregnancy

  • Use penicillins and cephalosporins (safe)
  • Avoid fluoroquinolones, tetracyclines
  • Pain control with acetaminophen; limit NSAIDs in 3rd trimester

Quality Metrics

Performance Indicators

MetricTargetRationale
CT for suspected deep space infection100%Identify abscess, plan surgery
Antibiotics covering anaerobes>5%Polymicrobial infection
Dental referral documented100%Definitive care
Airway assessment in Ludwig angina100%Life-threatening

Documentation Requirements

  • Source tooth identified
  • Swelling location and extent
  • Airway assessment
  • I&D performed (if applicable)
  • Antibiotics prescribed
  • Dental referral arranged

Key Clinical Pearls

Diagnostic Pearls

  • Percussion tenderness = periapical abscess: With decayed tooth
  • Trismus = deep space involvement: Not just localized abscess
  • Floor of mouth elevation = Ludwig angina: Emergent
  • CT for any concern of deep space infection: Don't delay
  • Most dental abscesses are polymicrobial: Aerobes + anaerobes
  • Diabetics and immunocompromised spread faster: Low threshold for admission

Treatment Pearls

  • Antibiotics alone may not be enough: I&D often needed
  • NSAIDs are excellent for dental pain: Ibuprofen 400-600 mg
  • Amoxicillin-clavulanate or clindamycin: Good outpatient choices
  • Ludwig angina needs early airway management: Before it's too late
  • Definitive treatment is dental: Extraction or root canal
  • Deep space = surgery: Oral maxillofacial or ENT

Disposition Pearls

  • Localized abscess can go home: With antibiotics and dental referral
  • Deep space infection = admit: IV antibiotics, possible OR
  • Ludwig angina = ICU: Airway and surgical management
  • All patients need dental follow-up: Prevention and definitive care

References
  1. Flynn TR, et al. Severe odontogenic infections. Dent Clin North Am. 2006;50(2):265-289.
  2. Bali RK, et al. A review of complications of odontogenic infections. Natl J Maxillofac Surg. 2015;6(2):136-143.
  3. Seppänen L, et al. Deep neck space infections: an upward trend. Int J Oral Maxillofac Surg. 2020;49(8):1037-1042.
  4. Vieira F, et al. Deep neck infection. Otolaryngol Clin North Am. 2008;41(3):459-483.
  5. Patterson HC, et al. Ludwig's angina: an update. Br J Oral Maxillofac Surg. 1982;20(2):83-91.
  6. Shemesh A, et al. Antibiotics in dentistry. Quintessence Int. 2018;49(1):80-92.
  7. American Dental Association. Dental Emergency Guidelines. 2019.
  8. UpToDate. Dental infections and deep neck space infections. 2024.

At a Glance

EvidenceStandard
Last UpdatedRecently

Guidelines

  • NICE Guidelines
  • BTS Guidelines
  • RCUK Guidelines