Face

Atlas References

• Netter: 42, 53–54, 83–85

• McMinn: 38–41

• Gray's Atlas: 503–506

Before You Begin

Review the superficial anatomy of the face:

• Glabella

• Root of nose, dorsum of nose

• Tip of nose

• Ala

• Columella nasi

• Philtrum

• Mental protuberance

• Modiolus

• Vermillion border

Palpate the following facial landmarks on the cadaver:

• Jugular notch

• Mental protuberance

• Nasion

• Glabella

• Vertex

• External occipital protuberance (inion)

• Mastoid process

• Ramus, angle, and body of mandible

• Zygomatic arch

• Infraorbital margin

• Supraorbital margin

• Superciliary arch

Skin and Superficial Fascia

• o

  With a marker, outline the dissection for the cadaver as follows ( Fig. 21.1 ):

  • 1.

    Make a line from the mental protuberance to the vertex. The line should encircle the lips, nostrils, and eyelids.

  • 2.

    Make a second line from the mental protuberance to the lobule of the ear.

  • 3.

    Make a third line from the vertex to the upper part of the helix of the ear.

  

• o

  Identify the six major surface regions (temporal, frontal, zygomatic, maxillary, mandibular, mental).

• o

  Based on the lines drawn, make an incision between the angle of the mandible and the mental protuberance ( Fig. 21.2 ).

  

• o

  Carefully reflect the flaps of skin (from medial to lateral) created by the incisions ( Figs. 21.3 and 21.4 ).

  
  

Anatomy Note

Beneath the skin, notice the surface of the face covered almost entirely by fat. This fibrofatty tissue is also known as the superficial musculoaponeurotic space or system (SMAS) ( Fig. 21.5 ).

Parotid Gland

• o

  Situated in front of the ear (auricle), the parotid gland is covered with variable amounts of fat. Using the separating technique with your scissors, reflect as much fat as possible.

• o

  Identify the substance of the parotid gland, which typically extends into the space between the zygomatic arch and the angle of the mandible ( Fig. 21.6 ).

  

• o

  Begin to reflect the SMAS medially over the mandibular region to reveal the parotid gland (see Fig. 21.5 ).

• o

  Continue to remove the SMAS from the mandibular region ( Fig. 21.7 ).

  

• o

  Identify the parotid duct , usually found emerging from the anterior edge of the parotid gland, about 1 inch (2.5 cm) inferior to the zygomatic arch ( Figs. 21.7 and 21.8 ).

  

Anatomy Note

From this point, the parotid duct passes horizontally across the masseter muscle, then turns around the anterior edge of the masseter and pierces the buccinator muscle ( Fig. 21.9 ).

• o

  Remove the SMAS from the maxillary and temporal regions (see Fig. 21.8 ).

• o

  Note the following structures: zygomaticus major muscle, masseter muscle, and temporal fascia (see Figs. 21.7 and 21.8 ).

• o

  Identify the buccal fat pad.

Mimetic Muscles

• o

  Clean the mimetic muscles, taking care to preserve the branches of the facial nerve, which innervate them.

• o

  Remove the SMAS from the orbital region and identify the frontalis and orbicularis oculi muscles (see Fig. 21.9 and Plate 21.1 ).

  

• o

  Identify the parts of the orbicularis oculi muscles:

  • o

    Orbital

  • o

    Palpebral

  • o

    Lacrimal

• o

  Identify the superficial temporal artery just superior to the zygomatic arch in front of the external acoustic meatus (see Fig. 21.9 ).

• o

  Identify several of the mimetic muscles ( Fig. 21.10 ):

  

• o

  The muscle surrounding the lips is the orbicularis oris .

• o

  Identify the zygomaticus major muscles.

• o

  Identify the zygomaticus minor muscles.

• o

  Identify the depressor anguli oris muscles.

• o

  Identify the depressor labii inferioris muscles.

• o

  Identify the levator labii superioris alaeque nasi muscles.

• o

  Identify the buccinator muscle.

• o

  The platysma muscle has been identified in the dissection of the neck (see Chapter 20 ).