Oral and Submandibular Regions

Question 1

What is the oral vestibule?

Answer 1

Space between the teeth and lips/cheek

Question 2

What is the oral cavity proper?

Answer 2

The space inside the teeth and anterior to the faucial pillars.

Question 3

What nerve provides the sensory innervation to the upper lip?

Answer 3

Infraorbital n. via it’s superior labial branch (CN V2)

Question 4

What nerves provide sensory innnervation to the lower lip?

Answer 4

Mental and buccal nn. (CN V3)

Question 5

How many permanent teeth are there (subtypes also)?

Answer 5

32 permanent teeth. Top and bottom each have 4 incisors, 2 canines, 4 pre-molar, and 6 molar.

Question 6

How many deciduous teeth are there?

Answer 6

16

Question 7

What are the origins and insertions of gingivae?

Answer 7

Maxillary and mandobular alveolar processes to the the neck of teeth.

Question 8

What is the sensory innervation of the maxillary gingivae?

Answer 8

The palatine portion of the maxillary gingivae is shared by nasopalatine and greater palatine nn. The external portion of the maxillary gingivae is innervated by the superior alveolar nn.

Question 9

What is the sensory innervation of the mandibular gingivae?

Answer 9

External portion of mandibular gingivae are innervated by buccal and inferior alveolar nn. Internal portion of the gingivae are innervated by the lingual n.

Question 10

What is the lymphatic drainage of the lips?

Answer 10

The entirety of the lips drain to the submandibular nodes, except the medial lower lip drains to the submental nodes.

Question 11

What is the lymphatic drainage of the teeth and its two exceptions?

Answer 11

The teeth drain to the submandibular nodes. Exceptions: mandibular incisors drain to the submental nodes and the 3rd maxillary molars drain to the superior deep cervical nodes.

Question 12

What parts of the tongue make up the body and the root?

Answer 12

Body = anterior 2/3 Root = posterior 1/3

Question 13

What are the external features of the tongue (9)?

Answer 13

Foramen cecum, terminal sulcus, median sulcus, median/lateral glossoepiglottic folds, lingual tonsils, papillae, epiglottic valleculae, and frenulum.

Question 14

What are the intrinsic muscles of the tongue and there actions?

Answer 14

Transverse - narrows tongue Longitudinal - shortens tongue Vertical - flattens tongue

Question 15

What is the innervation and action of the genioglossus?

Answer 15

Innervated by XII. Protrudes tongue b/l. Acting u/l pulls tongue towards opposite side.

Question 16

What is the innervation and action of the hyoglossus?

Answer 16

Innervated by CN XII. Retracts and depresses tongue.

Question 17

What is the innervation and action of the styloglossus?

Answer 17

Innervated by CN XII. Retracts and elevates tongue.

Question 18

What is the innervation and action of the palatoglossus?

Answer 18

Innervated by CN X. Pulls tongue and soft palate together.

Question 19

What type of fibers does CN XII provide to the mm. of the tongue?

Answer 19

GSE

Question 20

Describe the GSA/GVA innervation of the tongue.

Answer 20

Anterior 2/3 (GSA) = CN V3 via lingual n. Posterior 1/3 (GVA) = CN IX Epiglottic region (GVA) = CN X via internal laryngeal n.

Question 21

Describe the SVA innervation of the tongue.

Answer 21

Anterior 2/3 = CN VII via chorda tympani Posterior 1/3 = CN IX Epiglottic region = CN X via internal laryngeal n.

Question 22

Which portions of the tongue are the dorsal lingual, deep lingual, and sublingual aa. responsible for?

Answer 22

Dorsal lingual a. = posterior tongue and palatine tonsil Sublingual a. = floor of oral cavity Deep lingual a. = anterior tongue

Question 23

Describe the venous drainage of the tongue.

Answer 23

Lingual vv. drain the tongue and floor of the oral cavity to directly to the internal jugular v. via venae comitantes hypoglossi which parallels CN XII.

Question 24

Describe the lymphatic drainage of the tongue.

Answer 24

Posterior 1/3 of the tongue drains to superior deep cervical nodes. The Anterior 2/3 of the tongue drains to 3 different groups of nodes. The lateral portions drain to the submandibular nodes. Middle portion will drain to the inferior deep cervical nodes. Apex of tongue drains to the submental nodes.

Question 25

What are the four tonsils, where are they located, and what do they form together?

Answer 25

Together they form Waldeyer’s ring. Tubal tonsils - near opening of the auditory tube Pharyngeal tonsils - pharyngeal recess Palatine tonsils - b/w the faucial pillars Lingual tonsils - deep in the posterior 1/3 of tongue

Question 26

What are the pharyngeal tonsils referred to as when inflammed?

Answer 26

Adenoids

Question 27

Where is the sublingual gland located and how does it deliver fluid to the oral cavity?

Answer 27

The sublingual gland is found in the floor of the oral cavity just beneath the sublingual fold. It delivers salivary secretions to the oral cavity through small ducts which open in the sublingual fold.

Question 28

Describe the location of the submandibular gland and how it delivers secretions to the oral cavity.

Answer 28

The submandibular gland is found in the submandibular triangle and wraps around the mylohyoid m. dividing it into superficial and deep portions. The submandibular duct exits the deep portion anteriorly to pass over the lingual n. and dump into the oral cavity via the sublingual caruncle in the sublingual fold.

Question 29

Describe the parasympathetic innervation of the submandibular and sublingual glands.

Answer 29

Pre-gang cell bodies lie in the salivatory nucles and their fibers travel with CN VII and branch from VII with the chorda tympani. The chorda tympani joins lingual n. to run and synapse on post-gang cell bodies found in the submandibular ganglion. Post-gang fibers will rejoin the lingual nerve to distribute to the salivary glands.

Question 30

Describe the sympathetic innervation of the submandibular and sublingual glands.

Answer 30

Pre-gang cell bodies lie in the lateral horn of spinal cord segments T1-4. Their fibers ascend the sympathetic chain to synapse at the SCSG. Post-gang fibers distribute to these glands via the external carotid n. and facial and lingual aa.

Question 31

What is the innervation and action of the digastric m.?

Answer 31

Anterior belly innervated by mylohyoid n. (V) and posterior belly innervated by digastric n. (VII). Elevates the hyoid or opens the mouth when hyoid is fixed.

Question 32

What is the innervation and action of the stylohyoid?

Answer 32

Innervated by VII. Retracts and elevates the hyoid bone.

Question 33

What is the innervation and action of the mylohyoid?

Answer 33

Innervated by mylohyoid n. (V3). Elevates the oral cavity floor and assists in opening the mouth.

Question 34

What is the innervation and action of the geniohyoid?

Answer 34

Innervated by C1 via XII. Elevates the hyoid and assists in opening the mouth.

Question 35

What allows sublingual drug administration?

Answer 35

Sub drugs must be administered quickly. The sublingual vv. drain directly to the internal jugular v. allowing for rapid systemic distribution of drugs such as nitroglycerine.

Question 36

Describe the course of the Lingual N.

Answer 36

Passes through the paralingual space and wraps around the submandibular duct.

Question 37

Describe the course of XII.

Answer 37

Passes laterally around occipital a. after exiting the jugular foramen to enter the paralingual space.