	Headline
Etiology	Precipitated by caries. Strep and Staph most commonly implicated.
Clinical presentation	Look for - raised floor of mouth - airway compromise - downward spread towards mediastinum
Pathogenesis	Spreads along fascial planes as expected: maxilla → buccal or palate mandible → through alveolar bone to buccal/sublingual, occasionally submandicular or submasseteric
Diagnostic investigations	OPG Bloods only if systemically unwell
Management	If there is airway at risk, then follow Impending airway doom! and IV abx! If septic, then naturally Impending septic doom stuff applies I+D may be required Stable patient: Priority should be source control abx only indicated if: - Symptoms or signs of systemic illness, spreading infection e.g. cellulitis, lymph node involvement - High risk patients e.g. immunocompromised, diabetics - Abx of choice: Amox or metro or clarithromycin (no erythromycin - resistance)

key history aspects (copied shamelessly from RCEM)

When did the symptoms start?
Have antibiotics already been taken? Deterioration in a patient already taking antibiotics is concerning.
Has the patient seen a dentist? Most causes of mouth infection need definitive treatment. In general, ED care is a temporising measure.
Is the patient systemically unwell? This indicates potential spread of the infection beyond the tooth and gum. Consider Oral Sepsis.
Is the patient immunocompromised? e.g. diabetes, HIV, steroid use or general poor health.

non dental causes