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A swollen floor of the mouth after a toothache
A 42-year-old man has had a painful lower back tooth for a week. Over the last day his neck under the jaw has become hugely swollen and hard. He is drooling, can't swallow, and his tongue is pushed up and back. Temperature is 39.1 °C.
Step 1 of 4
What is the most likely diagnosis?
Correct answer: D
Brawny, woody submandibular swelling with an elevated, pushed-back tongue, drooling and dysphagia after a dental infection is Ludwig angina — rapidly spreading cellulitis of the submandibular space.
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D
Brawny, woody submandibular swelling with an elevated, pushed-back tongue, drooling and dysphagia after a dental infection is Ludwig angina — rapidly spreading cellulitis of the submandibular space.
Step 2 of 4
What is the first priority?
Correct answer: A
Ludwig angina is an airway emergency: secure the airway first, then give IV antibiotics and drain any collection.
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A
Ludwig angina is an airway emergency: secure the airway first, then give IV antibiotics and drain any collection.
Step 3 of 4
Why do infected lower molars spread into the submandibular space?
Correct answer: D
The roots of the lower molars lie below the mylohyoid line, so infection breaks out into the submandibular space beneath mylohyoid (see deep neck spaces).
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D
The roots of the lower molars lie below the mylohyoid line, so infection breaks out into the submandibular space beneath mylohyoid (see deep neck spaces).
Step 4 of 4
Once the airway is secure, which imaging test defines the infection?
Correct answer: C
Contrast CT of the neck (± chest) defines the spaces involved, distinguishes abscess from cellulitis and detects spread to the mediastinum.
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C
Contrast CT of the neck (± chest) defines the spaces involved, distinguishes abscess from cellulitis and detects spread to the mediastinum.
Key points
- Woody submandibular swelling + raised tongue after a dental infection → Ludwig angina.
- Airway first, then IV antibiotics; contrast CT once the airway is safe.
Study: Deep neck spaces, Submandibular gland, Mandible