Muscles of Mastication Anatomical Features Jaw Movements Articulators

Lateral Pterygoid

Medial Pterygoid Origin = Medial surface of lateral Pterygoid plate Insertion = medial wall of ramus and angle of mandible Nerve supply = Vmand – nerve to medial pterygoid Action = Elevation (+protrusion + medial)

Lateral Pterygoid Origin = Lateral surface of lateral pterygoid plat (+greater wing of sphenoid) Insertion = Neck of condyl and articular disc of TMJ Nerve supply = Vmand – Antr divn Nerve to lat ptery Action = Protrusion and opening

Lateral view of Mandible Coronoid process Condyle Ramus Body

Overview Glenoid Fossa Skull Zygomatic arch Temporal bone Mandible

Digastric Posterior belly Anterior belly Hyoid bone

Temporalis Origin = temporal surface of skull and temporal fascia Insertion = Coronoid process and antr border of ramus Nerve supply = Vmand – Antr divn Temporal nerve Action = Elevation (+retraction)

Masseter Origin = Zygomatic arch Insertion = Lateral wall of ramus and angle of mandible Nerve supply = Vmand – Antr divn Masseteric nerve Action = Clenching (+protrusion)

Base of Skull Lateral pterygoid plate Zygomatic arch Articular eminence Glenoid fossa

Interarticular disc

Masticatory muscle insertions 2 4 1 3 1 = Temporalis 2 = Masseter 3 = Lateral pterygoid 4 = Medial pterygoid

Condylar angle

Hinge Axis Rotation

Translation

Incisal Guidance

Condylar Guidance

Lateral Movements

Simple Hinge

Average Value

Denar II - Arcon

Fully Adjustable

Fully Adjustable

Denar II Adjustable Condylar Angle ISS & PSS