Mouth Flashcards
What are the boundaries of the oral cavity?
-front boundary: teeth and dental arches
-back boundary: oropharynx
-roof:
>hard palate (anterior 5/6 of palate), maxillary and palatine bones
>soft palate (posterior 1/6 of palate), uvula and muscle underneath
-floor of the mouth: mylohyoid and geniohyoid, contributions from the tongue
What are the structures associated with the soft palate?
3 muscles:
> palatopharyngeus muscle: posterior arch, from the posterior wall of the pharynx to the midline of the soft palate on both sides
> palatoglossus muscle: anterior arch, from the root of the tongue to the midline of the soft palate on both sides
> musculus uvulae: dangly smooth muscle which forms midline of soft palate
Palatine tonsils: between palatopharyngeal and palatoglossus arches
What are the innervations of the soft palate and pharynx?
Soft palate:
-sensory: CN5 V2, motor: CN10
Pharynx:
-sensory: CN9, motor: CN10
What is the clinical significance of the “say ahh” and “gag reflex” tests?
Used to assess CN9 and CN10
Gag reflex: tests for the sensory presence of a gag reflex (CN5&9)
“Say ahh”: tests more of the motor aspect (CN10)
Uvula should be symmetrical and elevate midline
Pathology: uvula will deviate to the strong side and away from the damaged side
(if CN10 is damaged on the right side, the uvula will deviate to the left/opposite side where it is stronger)
What are the structures of the tongue?
-Root: posterior section which attaches to the hyoid bone and spreads to anchor to the mandible (made primarily of lymph tissue)
-Body: anterior 2/3 of tongue, region where most of the tastebuds exist
-Apex: tip of tongue
What structures are associated with the inferior surface of the tongue?
-frenulum of tongue: midline structure, should be intact and symmetrical
-openings of the R/L submandibular ducts “Wharton’s ducts”: two distinct ducts located to each side of the frenulum
-openings of the sublingual glands: many smaller openings along the inferior surface of the tongue
What is the muscle of the tongue we are focusing on? What is it innervated by?
Tongue is made up of a mass of muscles that is mostly covered by mucosa
***Palatoglossus muscle that arches up and forms the anterior arch (emerges from the tongue)
-All tongue muscles are innervated by CN12 (hypoglossal) except for the palatoglossus which is innervated by CN10
GENIOHYOID AND MYLOHYOID ARE NOT MUSCLES OF THE TONGUE, THEY ARE A PART OF THE FLOOR OF THE MOUTH
What are the clinical applications for testing the tongue?
-Sticking the tongue out: assesses motor function of CN12
normal: will remain midline when stuck out
pathology of one side: tongue will deviate toward the damaged/weaker side
(If left side of CN12 is damaged, tongue will deviate toward the left)
What are the salivary glands of the mouth?
-Submandibular gland: in submandibular triangle (2 bellies of the digastric and mandible), wraps around and drains to the oral cavity/floor of the mouth through Wharton’s ducts
-Sublingual gland: in floor of the mouth, multiple openings (sublingual openings)
-Parotid gland: anterior or inferior to the external acoustic meatus “kind of on the outside of your cheek”, CN7 travels through the parotid to supply facial muscles after exiting the stylomastoid foramen, drains into the oral cavity through Stensen’s duct (near the upper 2nd molar on the cheek wall)
Why is it important to check openings/ducts?
If a stone or crystallization becomes lodges in one of the openings, they can become infected and cause a great deal of pain to the patient
