Oral and Maxillofacial Surgery
What this domain tests
Oral and maxillofacial surgery tests pre-operative assessment, third molar decision-making, odontogenic infection management, biopsy and referral, trauma, and recognition of airway-threatening conditions.
Core rules
- Third molars: describe angulation (Winter) and depth and ramus relationship (Pell and Gregory); assess root morphology, follicle, caries, periodontal status, and inferior alveolar nerve proximity.
- CBCT is indicated when the panoramic image shows the nerve crossing the roots, a narrowed canal, or a darkening of the root.
- Coronectomy is an option when the nerve is at high risk and the tooth is asymptomatic and non-infected.
- Odontogenic infection: determine the space involved, trismus, dysphagia, floor-of-mouth elevation, and systemic signs. Ludwig's angina is a bilateral submandibular-sublingual infection with airway risk and needs urgent drainage and intravenous antibiotics.
- Antibiotics are adjuncts; the primary treatment is removal of the cause and drainage.
- Document nerve status before surgery and record it again afterwards.
- Any lesion that does not resolve after cause removal needs biopsy or referral.
Worked example
A 27-year-old has a partially erupted 38, pericoronitis, 25-mm opening, temperature 38.2 degrees Celsius, submandibular swelling, and dysphagia. Reasoning: this is spreading infection with airway risk. Arrange urgent incision and drainage with intravenous antibiotics; extract or coronectomise only after resolution; request CBCT if the nerve is close.
Traps
Treating a facial space infection with oral antibiotics alone; extracting in the acute phase without drainage; failing to document nerve status.