Oral and Maxillofacial Surgery
What this domain tests
Preoperative assessment, safe surgical technique, recognition of complications, and emergency management of maxillofacial infection and trauma.
Core rules
- Third molar assessment uses Winter's classification of the long axis (mesioangular, distoangular, vertical, horizontal) plus depth (Pell–Gregory A/B/C) and relationship to the ramus (I/II/III). These predict difficulty and nerve risk.
- Ludwig's angina is a rapidly spreading bilateral submandibular/sublingual cellulitis with elevation of the floor of the mouth and airway threat. Priority is airway, then incision and drainage plus antibiotics - never a wait-and-see approach.
- Le Fort fractures: I is low (dental alveolus), II is pyramidal through the maxilla and nasal bones, III is craniofacial dysjunction through the zygomatic arch and orbital floor. All are confirmed by mobility of the maxilla against the cranium.
- MRONJ is defined by exposed bone or bone probing for more than eight weeks in a patient on antiresorptive or antiangiogenic therapy, with no history of radiotherapy.
- Dry socket presents as severe pain from days 2–4 with an empty, necrotic socket; treatment is irrigation and a medicated dressing, not repeat antibiotics.
Worked example
A patient on warfarin with an INR of 3.4 needs an extraction. Reasoning: do not simply stop therapy. Check the INR; elective surgery is deferred or the dose adjusted in consultation with the physician, aiming for a value within the therapeutic range for the procedure, with local haemostatic measures (sutures, haemostatic agent, tranexamic mouthwash).
Traps
- Assuming a panoramic radiograph excludes inferior alveolar nerve proximity - it shows superimposition only.
- Diagnosing dry socket on day 1.
- Describing Le Fort I as involving the orbit.