Oral Surgery · single question
A patient presents with mandibular deviation during opening AND closing movements. What is the most likely diagnosis?
Show answer and explanation
Correct answer: B. Displacement of the articular disc (right side)
B) Disc displacement — CORRECT.
Consistent mandibular deviation (toward the same side) during both opening and closing = disc displacement WITHOUT reduction (stuck disc). The condyle cannot translate properly on the affected side, causing the mandible to deflect toward that side throughout the movement.
Key distinction: Deviation = deflection to the same side throughout motion (disc displacement). Deflection with a click that then corrects = disc displacement WITH reduction.
A) Condylar fracture: Typically presents with acute trauma, pain, malocclusion, and limited opening — not primarily deviation during movement.
C) TMJ ankylosis: Severely limited opening — not just deviation.
D) Muscle splinting: Limits opening but does not cause consistent deviation in both opening and closing.
Consistent mandibular deviation (toward the same side) during both opening and closing = disc displacement WITHOUT reduction (stuck disc). The condyle cannot translate properly on the affected side, causing the mandible to deflect toward that side throughout the movement.
Key distinction: Deviation = deflection to the same side throughout motion (disc displacement). Deflection with a click that then corrects = disc displacement WITH reduction.
A) Condylar fracture: Typically presents with acute trauma, pain, malocclusion, and limited opening — not primarily deviation during movement.
C) TMJ ankylosis: Severely limited opening — not just deviation.
D) Muscle splinting: Limits opening but does not cause consistent deviation in both opening and closing.