Muscles of Mastication Quiz (ODS Learning Outcomes)

A powerful muscle involved in closing the mouth and chewing. It consists of two parts: the superficial and deep masseter.

The superficial masseter originates from the anterior two-thirds of the lower border of the zygomatic arch, which is the bone that forms the cheekbone.

The superficial masseter inserts on the outer surface of the ramus of the mandible, which is the vertical part of the jawbone.

The deep masseter originates from the posterior third of the lower border and the whole medial surface of the zygomatic arch.

The deep masseter inserts on the ramus of the mandible, above the angle of the mandible.

The masseter muscle contracts to close the mouth and elevate the mandible, allowing us to bite and chew.

The masseter muscle is supplied by the masseteric nerve, a branch of the mandibular nerve.

The masseter muscle receives blood supply from the facial branch of the superficial temporal artery and the masseteric branch of the maxillary artery.

A fan-shaped muscle situated on either side of the head, responsible for closing the jaw and pulling it backward.

The temporalis muscle originates from the entire temporal fossa, a region of the skull bounded by the inferior temporal line.

A muscle with two heads, the upper head originating from the infratemporal surface and crest of the greater wing of sphenoid bone, and the lower head originating from the lateral surface of the lateral pterygoid plate of the sphenoid bone. It inserts into the pterygoid fovea on the anterior aspect of the neck of the mandible, and its bilateral contraction opens and protrudes the mouth. Alternate contraction of the two pterygoid muscles on each side produces grinding or side-to-side movement.

Muscle with two heads, the deep head arising from the medial surface of the lateral pterygoid plate of the sphenoid bone, and the superficial head from the tuberosity of the maxilla and pyramidal process of the palatine bone. Inserts onto the medial surface of the ramus and angle of the mandible. Elevates the mandible and aids in protrusion.

Muscle with two bellies, the anterior belly arising from the digastric fossa on the lower border of the mandible, and the posterior belly from the digastric notch on the mastoid process of the temporal bone. They meet at an intermediate tendon above the hyoid bone. It is a depressor of the mandible and plays a crucial role in swallowing by elevating the hyoid bone.

Muscle which originates from the pterygomandibular raphe and buccal alveolar bone (in the region of the maxillary and mandibular molars). It inserts into the Orbicularis Oris muscle at the corners of the mouth. It pulls the corner of the mouth back, compresses the cheek against the molars, and regulates the space between the teeth and the cheek during chewing.

A narrow muscle that sits above the medial part of the mylohyoid line, originating from the inferior genial tubercle. It inserts into the body of the hyoid bone. It assists in swallowing and opening the mouth by depressing the mandible.

Muscle that originates from the superior genial tubercle on the inner surface of the mandible and inserts into the dorsum of the tongue. It forms a fan-shaped muscle with superior fibers reaching the tip of the tongue and inferior fibers inserting onto the hyoid bone. Depresses the tongue, retracts the tongue (inferior fibers), and protrudes the tongue (superior fibers).

Fibers run obliquely and horizontally, contracting to elevate the mandible and retract the head of the condyle back into the glenoid fossa.

Nerve supply to the Posterior Temporalis.

Blood supply to the Posterior Temporalis.

Muscles that move the mandible (jaw) to aid in mastication (chewing) and speaking. They all receive blood from the major arteries of the head and neck.