Oral and Maxillofacial Surgery
What this domain tests
OMFS tests exodontia, impacted teeth, infection, trauma, temporomandibular joint problems and biopsy. The exam emphasises red flags and safe referral.
Core rules
- Extraction assessment includes medical history (anticoagulants, bisphosphonates, radiotherapy), tooth and root morphology, bone density, and proximity to the inferior alveolar nerve and maxillary sinus.
- Third molar assessment includes angulation, depth, root morphology and relationship to the canal; coronectomy may be considered when nerve risk is high.
- Dry socket causes severe pain 2-4 days after extraction with an empty socket and no pus; treat with irrigation and dressing, not routine antibiotics.
- Odontogenic infection with trismus, swelling, dysphagia, raised floor of mouth or systemic signs needs urgent care. Ludwig's angina is bilateral submandibular and sublingual cellulitis; secure the airway and drain surgically.
- Maxillofacial trauma includes Le Fort I, II and III patterns. Mandibular fractures commonly involve the angle, condyle and symphysis; assess occlusion, paresthesia and mobility.
- Incisional biopsy is used for large or suspicious lesions; excisional biopsy for small benign lesions. Send in formalin unless fresh tissue is required.
- Document pre-operative sensation when inferior alveolar, lingual or buccal nerve injury is possible.
Worked example
A patient has submandibular swelling, trismus, fever and a raised floor of mouth after a lower molar infection. This is not a simple abscess for oral antibiotics alone. The correct action is urgent referral for airway assessment, intravenous antibiotics and surgical drainage; delay risks airway compromise.
Traps
- Paresthesia after extraction is not normal; document and review.
- Do not prescribe antibiotics for dry socket without systemic infection.
- A plain radiograph may underestimate root proximity to the canal; use CBCT when indicated.
- If the airway is threatened, drainage takes priority over extraction.