ENT · Infectious Disease
The facts most likely to be tested
The primary treatment for a dental abscess is definitive source control via incision and drainage or root canal therapy.
Ludwig angina is a life-threatening bilateral cellulitis of the submandibular space that typically arises from an infected second or third mandibular molar.
Patients with Ludwig angina present with a woody induration of the floor of the mouth and elevated tongue, necessitating immediate airway protection.
Polymicrobial flora including Streptococcus viridans and anaerobes are the most common causative organisms in odontogenic infections.
Antibiotic therapy is indicated as an adjunct for patients with systemic signs of infection, cellulitis, or immunocompromise, with amoxicillin-clavulanate or clindamycin as first-line choices.
Trismus (inability to open the mouth) is a classic clinical sign indicating masticator space involvement and potential deep neck space infection.
Contrast-enhanced CT of the neck is the diagnostic imaging modality of choice to evaluate for abscess formation and deep neck space extension.
Vignette unlocked
A 34-year-old male presents to the emergency department with a 3-day history of severe tooth pain and progressive swelling under his chin. Physical examination reveals a febrile patient with bilateral submandibular swelling, woody induration of the floor of the mouth, and an elevated, displaced tongue. He is drooling and has difficulty speaking. His airway appears patent but is at high risk for rapid compromise.
What is the most appropriate next step in management?
Secure the airway via endotracheal intubation
The patient presents with classic signs of Ludwig angina; the most critical priority is securing the airway due to the risk of rapid obstruction from the expanding submandibular space infection.
Full handout
High yield triage
Etiology / Epidemiology
Common in patients with poor dental hygiene and untreated caries. Often polymicrobial, involving viridans group streptococci.
Clinical Manifestations
Localized throbbing pain, fever, and swelling. Ludwig's angina is the feared, rapidly progressive submandibular space infection.
Diagnosis
Clinical diagnosis confirmed by CT scan with contrast to evaluate for deep space involvement.
Treatment
Amoxicillin is first-line. Airway compromise requires immediate surgical consultation and drainage.
Prognosis
Most resolve with drainage and antibiotics; cavernous sinus thrombosis is a rare, life-threatening complication.
Full handout
Epidemiology & Etiology
Primarily caused by dental caries, trauma, or periodontal disease leading to pulp necrosis. Most infections are polymicrobial, involving both aerobic and anaerobic flora. Poor oral hygiene and diabetes mellitus are significant risk factors for severe progression.
Pertinent Anatomy
Infections originate in the periapical region or periodontal pocket. The fascial planes of the neck act as conduits for infection spread to the mediastinum or intracranial spaces.
Pathophysiology
Bacterial invasion of the dental pulp leads to inflammation and necrosis. The confined space of the tooth prevents immune cell infiltration, allowing for abscess formation. Pressure builds, causing intense pain and potential spread into adjacent soft tissues.
Clinical Manifestations
Patients present with localized pain, erythema, and fluctuance. Trismus, dysphagia, and drooling are red flags for deep space involvement. Ludwig's angina presents as bilateral submandibular swelling with an elevated tongue.
Diagnosis
Diagnosis is primarily clinical based on physical exam. CT scan with contrast is the gold standard for identifying deep space abscesses or osteomyelitis. Obtain imaging if there is evidence of airway compromise or systemic toxicity.
Treatment
Definitive treatment is incision and drainage (I&D) of the abscess. Amoxicillin is the first-line antibiotic; use clindamycin for penicillin-allergic patients. Airway obstruction is a medical emergency requiring immediate ENT consultation.
Prognosis
Prompt drainage usually leads to rapid recovery. Cavernous sinus thrombosis and mediastinitis are rare but high-mortality complications requiring aggressive inpatient management.
Differential Diagnosis
Periodontitis: inflammation of gums without discrete abscess
Temporomandibular joint disorder: pain without fever or swelling
Parotitis: swelling localized to the preauricular area
Sialadenitis: stone-related ductal obstruction
Osteomyelitis: bone involvement confirmed by imaging