Expansion
My Try Might Ache
Mnemonic
“Three close, one opens”, all supplied by V3:
- M - Masseter, closes
- T - Temporalis, closes and retracts
- M - Medial pterygoid, closes
- L - Lateral pterygoid, opens and protrudes
“The lateral pterygoid is the odd one out”: it is the only one that opens the jaw, and it is the muscle that pulls the mandible forwards, which is why unilateral weakness makes the jaw deviate towards the weak side on opening.
All four develop from the first pharyngeal arch, which is why they share the mandibular nerve, alongside tensor tympani, tensor veli palatini, mylohyoid and the anterior belly of digastric.
Expansion
- M - Masseter
- T - Temporalis
- M - Medial pterygoid