Head Structures
Pages: 225-238
Pages 245-260
The superficial muscles move skin and ears, eyelids, nose, and lips to produce facial expression. The platysma m. (1) runs from the neck to the commissure of the lips. It retracts the lips to expose teeth; parts of the muscle are missing (asterisks). Superficial muscles that move the ear may be grouped into rostral (2), lateral (3), and caudal auricular muscles. An orbicularis oculi m. (4) closes the palpebral fissure.
A levator nasolabialis m. (5) retracts the nose and upper lip. An orbicularis oris m. is situated within the lips (6).
Muscles of the lips and cheek. The orbicularis oris m. (1) is located within the wall of the upper lip and the lower lip. The buccinator m. (2) is located within the wall of the cheek. The levator nasolabialis m. (3) retracts the nose and upper lip. The orbicularis oculi m. (4) closes the palpebral fissure.
Superficial muscles move the ear. Identify rostral auricular mm. (1) which attach to a scutiform cartilage (2) plate in addition to attaching to the auricular cartilage (3) which forms the pinna (auricle) of the ear.
The palpebral fissure (opening) is situated between superior (1) and inferior (2) palpebrae.
The eyelids meet at medial (3) and lateral (4) palpebral commissures. The lateral commissure (forceps) has been incised.
Third eyelid (5), has a pigmented edge.
Oral cavity in a bisected cadaver. The vestibule is lateral to the teeth. Notice the large fourth premolar (asterisk).
Within the oral cavity proper, the tongue (1) is reflected and floor mucosa has been incised to reveal the polystomatic sublingual salivary gland (2) and mandibular and sublingual salivary ducts (3) emptying at the sublingual caruncle (4).
The parotid salivary gland (1) surrounds the external ear canal (2) and sends a parotid duct (3) toward the vestibule. It empties beside the upper fourth premolar.
The mandibular salivary gland (4) is located where the maxillary v. (5) and linguofacial v. (6) join to form the external jugular v. (7).
The monostomatic sublingual salivary gland (8) is located just cranial to the mandibular salivary gland. Notice the mandibular lymph nodes (9) flanking the facial v.
Deep dissection. The temporal m. has been reflected to expose the temporal fossa (1). The top of the ramus (2) of the mandible has been remove and the ramus has been reflected laterally to expose vessels and nerves on the surface of the medial pterygoid m. (3). The zygomatic salivary gland (4) is located ventral to the orbit which has been incised to expose the eye (5) and extrinsic eye muscles (6).
The pharynx is subdivided by the soft palate (1) into a nasopharynx (2), an oropharynx (3), and a laryngopharynx (4).
The palatopharyngeal arch (6) marks the caudal end of the soft palate. The pharyngoesophageal limen (7) marks the boundary between the pharynx and esophagus.
Enlarged view of the pharynx. The pharynx is subdivided by the soft palate (1). The nasopharynx (2) contains the opening of the auditory tube (3). The oropharynx (4) contains the palatine tonsil (5) within a fossa normally covered by a semilunar fold (6). The palatopharyngeal arch (7) marks the caudal end of the soft palate. The laryngopharynx (8) is located caudal to the soft palate and dorsal to the larynx.
Choanae (openings) at the caudal end of the hard palate (1) mark the boundary between nasal cavity and nasopharynx (2). The palatoglossal arch (3) marks the boundary between oral cavity (4) and oropharynx (5). The palatopharyngeal arch (6) marks the end of the soft palate (7). The pharyngoesophageal limen (8) marks the boundary between the laryngopharynx (9) and the esophagus (10). Identify the epiglottis (11) and other laryngeal cartilages (12).
Dorsal nasal concha (1) and the ventral nasal concha (2). The conchae divide nasal cavity space into a dorsal nasal meatus (3), a middle nasal meatus (4), and a ventral nasal meatus (5). The nasolacrimal duct opens (6) on the rostromedial surface of the alar fold (7)
ethmoidal labyrinth (8), located caudally in the nasal cavity.
Muscle of Mastication: the temporal m. (2) and the masseter m. (3). Also identify the digastricus m. (4), auricular cartilage (5), and the mandibular (6) and monostomatic sublingual (7) salivary glands. Notice the fourth upper premolar and first lower molar teeth (asterisks).
Temporal m. (2), the partially reflected masseter m. (3), the mandible (4), and the digastricus m. (5). Notice the fourth upper premolar and first lower molar teeth (asterisks).
The zygomatic arch has been removed and the masseter m. (1) has been reflected. Notice the ramus of the mandible (2) and the temporomandibular joint (3). Also find the temporal m. (4) and the digastricus m. (5).