Oral Cavity Flashcards
Oral cavity
Consists of two portions: Oral vestibule and oral cavity (proper)
Oral Vestibule
Slit-like space between lips and teeth. Contains labial frenula pterygomandibular raphe, and parotid papilla
Labial frenula
Folds of mucous membrane between gingiva and mucosa of upper/lower lips. Attaches lip to maxillary ridge
Pterygomandibular Raphe
Junction area between buccinator and superior constrictor muscles
Parotid Papilla
Opening of the parotid duct inside the oral vestibule. Opposite the second maxillary molar
Boundaries of the Oral Cavity Proper
Lateral: Upper and lower dental arches (maxillary and mandibular teeth), Posterior: Opening in the back of the oral cavity, Roof: hard and soft palates, and Floor lined with mucous membrane along with its contents
Posterior boundary of oral cavity
Place for communication with the oropharynx, components/contents: oropharyngeal isthmus, palatopharyngeal arch, palatoglossal arch, and palatine tonsils
Oropharyneal isthmus
Found in the posterior portion of the oral cavity. Connecting area between the oral cavity and pharynx
Palatopharyngeal Arch
Found in the posterior portion of the oral cavity. More posteromedial than the palatopharyngeal arch. Formed by the underlying palatopharyngeus muscle
Palatoglossal Arch
Found in the posterior portion of the oral cavity. More anterolateral than the palatopharyngeal arch. Formed by the underlying palatoglossus muscle.
Palatine Tonsils
Found in the posterior portion of the oral cavity. Lymphoid tissue, bounded by the palatoglossal and palatopharyngeal arches.
Hard palate
Formed by palatine process of the maxilla and horizontal plates of palantine bone. Contains: incisive foramen, greater and lesser palatine foramen, palatine glands, and palatine rugae
Incisive foramen
Nasopalatine nerve and sphenopalatine artery pass through
Greater palatine foramen
Greater palatine vessels and nerve pass through to supply the mucosa of the hard palate
Lesser palatine foramen
Lesser palatine vessels and nerve pass through to supply the mucosa of the soft palate
Palatine glands
small glands located in the mucosa of the hard palate. Purely mucous glands
Palatine Rugae
Transverse folds of the mucus membrane holding the hard palate. Help facilitate the movement of food backwards toward the pharynx
Soft Palate
Soft tissue in the back of the roof of the oral cavity. Does not contain bone. Contains 5 muscles important for swallowing and breathing: levator veli palatini, tensor veli palatini, palatoglossus, palatopharyngeus, and musculus uvulae
Levator veli palatini
Muscle from eustachian tube to palatine aponeurosis (connective tissue of the soft palate). Raises (levator, duh) the soft palate during swallowing. Supplied by CN IX, X, XI
Tensor Veli Palatini
Muscle from eustachian tube to palatine aponeurosis (connective tissue of the soft palate). Tenses (tensor, duh) the soft palate. Its tendon hooks around the pterygoid hamulus. Supplied by CNV
Palatoglossus
From palatine aponeurosis of soft palate to side of the tongue. Forms the palatoglossal arch. Classified as a muscle of the palate rather than a tongue muscle. Supplied by pharyngeal plexus (CN IX, X, and XI)
Palatopharyngeus
From the palatine aponeurosis of soft palate to upper part of the wall of the pharynx. Forms the palatopharyngeal arch. Supplied by CN IX, X, XI
Musculus Uvulae
A finger-like process at the posterior part of the soft palate. Inserts into the muscosa of the soft palate, lies entirely in the uvula. Shortens and broadens the uvula, and changes the contour of the posterior part of the soft palate.
Floor of the Mouth
Lined with a thin mucus membrane. Mucosa allows the drugs (e.g. nitroglycerine for vasodilation) to be absorbed into venous system in less than a minute. Contents include lingual frenulum, sublingual papilla, submandibular ducts, sublingual fold, sublingual gland and partially the tongue
Lingual frenulum
Fold of mucus membrane that extends from the gingiva to the inferior aspect of the tongue
Sublingual Papilla
Located at the base of the lingual frenulum (one on each side). Nipple-like structures representing the opening of the ducts of submandibular gland
Submandibular Ducts
One duct from each gland. Open at the sublingual papillae in the floor of the mouth
Sublingual Fold
Raised area on each side of the lingual frenulum, caused by sublingual gland covered by mucus membrane.
Sublingual Gland
Smallest and most deeply located of the three salivary glands. Lie in the floor of the oral cavity between the mandible and the genioglossal muscle. Each gland has numerous ducts that open in the floor of the mouth.
Tongue
Partly in the oral cavity, partly in the oropharynx. Assists in mastication, speech, swallowing, taste, cleaning the oral cavity, and lollipops. Consists of a root (posterior 1/3, rests on the floor of the mouth) and a body (anterior 2/3, freely movable, anterior pointed part is the apex).
Dorsum of the tongue
Anterior 2/3 of the dorsum of the tongue covered in filliform papillae, fungiform papillae, vallate (circumvallate) papillae, and follate papillae. Contains sulcus terminalis, median groove (sulcus) and septum, and lingual tonsil. Two types of muscles of the tongue: Intrinsic muscles (confined to the tongue) and extrinsic muscles (originating outside the tongue: Genioglossus, hyoglossus, styloglossus, palatoglossus).
Sulcus Terminalis
Inverted v-shaped groove on the dorsum of the tongue. Marks separation of anterior 2/3 from posterior 1/3.
Foramen Cecum
Median pit on posterior dorsum of tongue. Sulcus terminalis extends anteriorly and laterally from either side. Thyroglossal duct –> Thyroid extends from here
Median Groove (sulcus)
Separates two “hemispheres” of the tongue. Indicates the site of fusion of the two embryonic lingual buds. NOTE: no blood vessels of nerves pass across this groove, which is why some weird people are able to bissect their tongue along this groove.
Filiform papillae
Small hair-like structures. Cover the enter surface of the tongue. Contain afferent nerve endings sensitive to touch. Can get “hairy tongue” from an accumulation of keratin on the filiform papillae.
Fungiform papillae
Small mushroom-like structures scattered among the filliform papillae. Mostly on the tips and sides.
Vallate Papillae
Largest papillae (12-18 in number). Lie anterior to the sulcus terminale. Each papilla is surrounded in a trench that contains numerous taste buds
Folliate Papillae
Small folds of mucosa along the lateral sides of the tongue
Lingual Tonsil
Lymphoid tissue located on the posterior 1/3 of the tongue. The mucus membrane here is thick and looks very lumpy.
Intrinsic muscles of the tongue
Innervated by CN XII. Consist of fibers that run longitudinally, vertically and transversally. Confined to the tongue and do not have a bony attachment. They function to change the shape of the tongue.
Extrinsic Muscles
Originate from outside the mouth. Genioglossus, hyoglossus, styloglossus, palatoglossus.
Genioglossus Muscle
Innervated from CN XII. Runs from chin to tongue. Two muscles (each side) working together are major muscles for sticking tongue out. Unilateral contraction pushes tongue towards contralateral (opposite) side of muscle. Paralysis of the muscle causes the tongue to shifts posteriorly and can lead to suffocation (can happen during general anesthesia)
Hyoglossus Muscle
Innervated by CN XII. Works to depress the tongue
Styloglossus Muscle
Innervated by CNXII. Works to retrude the tongue
Palatoglossus Muscle
Innervated by pharyngeal plexus. Elevates posterior portion of the tongue.
Motor innervation of the tongue
CN XII and Pharyngeal Plexus
Sensory Innervation of Anterior 2/3 of tongue
Lingual Nerve (Branch of Trigeminal Nerve): carries general sensation. Chorda Tympani (From CNVII): provides special sensory fibers to taste buds (except to taste buds in the vallate papillae)
Sensory innervation of posterior 1/3 of tongue
CNIX: Carries general senstation and taste (including vallate papillae). CNX: supplies area around epiglottis
Blood supply to tongue
Lingual artery (a branch of external carotid) supplies tongue. Veins terminate in internal jugular vein.
