• Long bones (e.g.. femur and humerus)
• Short bones (e.g.. wrist and ankle bones)
• Flat bones (e.g.. ribs)
• Irregular bones (e.g.. vertebrae)

Veins of the Face

The Supratrochlear Vein

• This vessel begins on the forehead from a network of veins connected to the frontal tributaries of the superficial temporal vein.
• It descends near the medial plane with its fellow on the other side.
• These veins diverge near the orbits, each joining a supraorbital vein to form the facial vein near the medial canthus (angle of the eye).

The Supraorbital Vein

• This vessel begins near the zygomatic process of the temporal bone.
• It joins the tributaries of the superficial and middle temporal veins.
• It passes medially and joins the supratrochlear vein to form the facial vein near the medial canthus.

The Facial Vein

• This vein provides the major venous drainage of the face.

• It begins at the medial canthus of the eye by the union of the supraorbital and supratrochlear veins.
• It runs inferoposteriorly through the face, posterior to the facial artery, but takes a more superficial and straighter course than the artery.
• Inferior to the margin of the mandible, the facial vein is joined by the anterior branch of the retromandibular vein.
• The facial veins ends by draining into the internal jugular vein.

The Superficial Temporal Vein

• This vein drains the forehead and scalp and receives tributaries from the veins of the temple and face.
• In the region of the temporomandibular joint, this vein enters the parotid gland.

The Retromandibular Vein

• The union of the superficial temporal and maxillary veins forms this vessel, posterior to the neck of the mandible.
• It descends within the parotid gland, superficial to the external carotid artery but deep to the facial nerve.
• It divides into an anterior branch that unites with the facial vein, and a posterior branch that joins the posterior auricular vein to form the external jugular vein.

The Medial Pterygoid Muscle

• This is a thick, quadrilateral muscle that also has two heads or origin.
• It embraces the inferior head of the lateral pterygoid muscle.
• It is located deep to the ramus of the mandible.

• Origin: deep head—medial surface of lateral pterygoid plate and pyramidal process of palatine bone, superficial head—tuberosity of maxilla.
• Insertion: medial surface of ramus of mandible, inferior to mandibular foramen.
• Innervation: mandibular nerve via medial pterygoid nerve.

• It helps to elevate the mandible and closes the jaws.
• Acting together, they help to protrude the mandible.
• Acting alone, it protrudes the side of the jaw.
• Acting alternately, they produce a grinding motion.

• This is the second cranial nerve (CN II) and is the nerve of sight.

Extrinsic Muscles of the Tongue (p. 746)

The Genioglossus Muscle

• This is a bulky, fan-shaped muscle that contributes to most of the bulk of the tongue.
• It arises from a short tendon from the genial tubercle (mental spine) of the mandible.
• It fans out as it enters the tongue inferiorly and its fibres attach to the entire dorsum of the tongue.
• Its most inferior fibres insert into the body of the hyoid bone.
• The genioglossus muscle depresses the tongue and its posterior part protrudes it.

The Hyoglossus Muscle

• This is a thin, quadrilateral muscle.
• It arises from the body and greater horn of the hyoid bone and passes superoanteriorly to insert into the side and inferior aspect of the tongue.
• It depresses the tongue, pulling its sides inferiorly; it also aids in retrusion of the tongue.

The Styloglossus Muscle

• This small, short muscle arises from the anterior border of the styloid process near its tip and from the stylohyoid ligament.
• It passes inferoanteriorly to insert into the side and inferior aspect of the tongue.
• The styloglossus retrudes the tongue and curls its sides to create a trough during swallowing.

The Palatoglossus Muscle 

• Superior attachment: palatine aponeurosis.
• Inferior attachment: side of tongue.
• Innervation: cranial part of accessory nerve (CN XI) through the pharyngeal branch of vagus (CN X) via the pharyngeal plexus.

• This muscle, covered by mucous membrane, forms the palatoglossal arch.

• The palatoglossus elevates the posterior part of the tongue and draws the soft palate inferiorly onto the tongue.

Nerves of the Face

Innervation of the Muscles of Facial Expression

The Facial Nerve (CN VII)

• The seventh cranial nerve supplies the superficial muscle of the neck (platysma), the muscles of facial expression, the auricular muscles and the scalp muscles.
• CN VII is the sole motor supply to the muscles of facial expression.

• The facial nerve emerges from the skull though the stylomastoid foramen.
• Almost immediately, it enters the parotid gland. It runs superficially in this gland before giving rise to its five terminal branches: temporal, zygomatic, buccal, marginal mandibular, and cervical.
• These nerve emerge from the superior, anterior and inferior margins of the gland and spread out like the abducted digits of the hand to supply the muscles of facial expression.

• The temporal branches of CN VII cross the zygomatic arch to supply all the superficial facial muscles superior to it, including the orbital and forehead muscles.

• The zygomatic branch of CN VII passes transversely over the zygomatic bone to supply the muscles in the zygomatic, orbital and infraorbital regions.

• The buccal branches of CN VII pass horizontally, external to the masseter muscle, to supply the buccinator and the muscles of the upper lip.

• The marginal mandibular branch of CN VII supplies the muscles of the lower lip and chin.

• The cervical branch of CN VII supplies the platysma and the superficial muscles of the neck.