Exam #2

Origin

The end of a muscle that is attached to the least movable structure.

Insertion

The end of a muscle that is attached to a more movable structure.

Zygomaticus Major Muscle

A muscle of facial expression that elevates the labial commissure of the upper lip and pulls it into a smile.

Masseter Muscle

The most superficial and strongest muscle of mastication, which can become enlarged due to clenching or grinding teeth.

Mandibular Notch

The curvature depression between the coronoid and condylar processes, allowing passage for the masseteric nerve and vessels.

Mandibular Foramen

The landmark ligament for giving the inferior alveolar nerve block.

Subluxation

An acute episode of temporomandibular disorder occurring when a patient opens the mouth widely or receives prolonged dental care.

Articular Fossa

A depression in the temporal bone where the mandibular condyle articulates to form the TMJ.

Interocclusal Clearance

The gap between the jaws that allows for physiological rest of the mandible.

Lateral Pterygoid

A short, thick muscle superior to the medial pterygoid that is responsible for lateral deviation of the mandible.

Facial Nerve

The cranial nerve that innervates the muscles of facial expression.

Platysma

A muscle of facial expression that runs from the neck to the mouth.

Lingual Septum

A structure that divides the tongue into symmetrical halves.

Tensor Veli Palatini

The muscle involved in speaking, swallowing, and middle ear function.

Nasalis/Alar

The muscles that dilate the nostrils, flaring them.

Omohyoid

An infrahyoid muscle with two bellies connected by an intermediate tendon that depresses the hyoid bone.

Epicranial Aponeurosis/Galea Aponeurotica

A large spread-out scalpel tendon that raises the eyebrows and scalp when a person shows surprise.

Joint Disc

A fibrous disc located between the temporal bone and mandibular condyle that cushions the joint.

Styloglossus Muscle

An extrinsic tongue muscle that helps retract and elevate the tongue.

Orbicularis Oris

Muscle of facial expression in the oral region that moves by closing, pursing, grimacing, and pouting.

Protrusion

The movement of bringing the mandible forward.

Retraction

The movement of bringing the mandible backwards.

Elevation

The action of raising the mandible (closing).

Depression

The action of lowering the mandible (opening).

Lateral Deviation

The movement of shifting the jaw to one side.

Synovial Fluid

Fluid secreted by the membrane lining inside the joint capsule for lubrication.

Hypoglossal Nerve

The nerve innervating the extrinsic tongue muscle (styloglossus muscle).

Facial Paralysis

The inability to move facial muscles caused by nerve damage.

Action

The movement accomplished when the fascicles contract.

Sternocleidomastoid Muscle

Thick neck muscle that divides the neck into anterior and posterior cervical triangles.

Trapezius Muscle

Broad, flat, triangular muscle that lifts the clavicle and scapula, especially when shoulders are shrugged.

Epicranial Muscle/Epicranius

Muscle of facial expression in the scalp region, with two bellies located in the frontal and occipital regions.

TMJ Ligaments

Includes the temporomandibular ligament, stylomandibular ligament, and sphenomandibular ligament.

Muscles of Mastication

Includes the masseter, temporalis, medial pterygoid, and lateral pterygoid.

Intrinsic Tongue Muscles

Muscles that control the shape of the tongue (e.g., curling, flattening, elongating).

Extrinsic Tongue Muscles

Muscles that control the movement of the tongue (e.g., protrusion, retraction, elevation, depression).