Boundaries of oral cavity
- Vermillion border to junction of hard and soft palate
2. Circumvallate papillae (linea terminalis)
Subunits of oral cavity
- Lip
- Buccal mucosa
- Upper and lower alveolar ridges
- Retromolar trigone
- Oral tongue (anterior to circumvallate papillae)
- Hard palate
- Floor if mouth
Boundaries of oropharynx
- Junction of hard and soft palate
2. Circumvallate papillae to valleculae (plane of hyoid bone)
Subunits of oropharynx
- Soft palate and uvula
- base of tongue
- pharyngoepiglottic and glossoepiglottic folds
- palatine arch (fossae with palatine tonsils and pillars)
- valleculae
- lateral and posterior pharyngeal walls
boundaries of hypopharynx
level of hyoid bone to level of inferior border if cricoid cartilage
subunits of hypopharynx
- pyriform sinus
- posterior and lateral pharyngeal walls
- postcricoid region
boundaries of esophagus
from cricoid cartilage to cardia of stomach
subunits of esophagus
- UES
- body
- LES
dimensions of esophagus
16 cm: incisors to cricopharyngeal sphincter
38-40cm: incisors to stomach
orifice is lateral to 2nd molars
parotid (stenson’s)
orifice is in midline floor of mouth adjacent to lingual frenulum
submaxillary (wharton’s)
multiple orifices draining into floor of mouth or into submaxillary duct
sublingual (rivinu’s)
covercthe anterior 2/3 of rhe tongue including filiform (no taste function) fungiform (diffuse) and foliate (lateral tongue)
papillae
are large and lie in a V-shape at the juction of the anterior and posterior portions of the tongue
circumvallate papillae
a groovw at the anterior margin of the circumvallate papillae
sulcus terminalis
a pit at the junction of the sulcus terminalis from which the embryologic thyroid begins its descent
foramen cecum
anterior fold of mucous memnrane attaches the anterior inferior aspect of the tongue to the floor of mouth and gingiva
frenulum
lymphoid tissue extending over the base of the tongue
lingual tonsil
depressions on either side of the midline glossoepiglottic fold extending to the level of the hyoid bone
valleculae
extrinsic muscles of tongue
CN XII
- genioglossus
- hyoglossus
- styloglossus
- palatoglossus
intrinsic muscles of tongue
CN XII
- superior and inferior longitudinal
- vertical
- transverse
defines midline and contains a triangular fat pad
fibrpus septae (septum linguae)
sensations of tounch, pain, temperature transmitted via lingual nerve (V3)
anterior 2/3 of the tongue (oral tongue)
taste sensation on the anteririor 2/3 of tongue is transmitted via…
lingual nerve to chorda tympani
taste
papillae—afferent fibers—lingual nerve—chorda tympani—geniculate ganglion—intermediary nerve—nucleus solitarius
touch and gag (visceral afferent) sensation of posterior 2/3 is transmitted via…
CN IX to nucleus solitarius
vascular supply of tongue
lingual artery (2nd branch of external carotid) lingual vein (travels with hypoglossal nerve)
lymphatic drainage
anterior tongue
central drains to ipsilateral and contralateral nodes, tip to submental nodes, and marginal (lateral) to ipsilateral nodes
lymphatic drainage
posterior tongue
ipsilateral and contralateral deep cervical nodes (jugulodigastric)
forms the anterior 2/3 of the palate and consists of the palatine process of the maxilla and horizontal plates of the palatine bones
hard palate
hard palate epithelium
stratified squamous epithelium
foramina of the palate
- greater palatine foramen
- accessory palatine foramen
- incisural foramen
conveys descending palatine branch of V2 to innerbate palate as well as descending palatine artery
is 1 cm medial to 2nd molar
greater palatine foramen
posterior to greater palatine foramen
conveys lesser descending palatine artery to soft palate
accessory palatine foramen
lies midline of anterior palate
transmits incisural artery to anterior septum
incisural foramen
blood supply to palate
maxillary artery—
descending palatine artery
1. greater palatine artery (hard palate)
2. lesser palatine artery (soft palate)
venous drainage
hard palate veins
—>pterygoid plexus—>internal jugular
venous drainage
soft palate veins
- pharyngeal plexus—>internal jugular
2. external palatine—>tonsillar fossa—>facial vein or pharyngeal vein
total saliva
1500ml/d
saliva
when unstimulated, 2/3 are secreted by…
submaxillary glands
saliva
when stimulated, 2/3 are secreted by…
parotid glands
saliva components
- 5% water
0. 5% organic or inorganic solids
electrolyte components of saliva
Na 10 mEq/L
K 26 mEq/L
Chlorine 10 mEq/L
bicarbonate 30 mEq/L
pH of saliva
6.2 to 7.4
organic component of saliva
- glycoprotein
2. amylase
muscles of mastication
- masseter
- temporal
- lateral pterygoid
- medial pterygoid
blood suppky of muscles of mastication
branches of maxillary artery
nerve supply of muscles of mastication
V3 (motor branch)
muscles of soft palate
- palatoglossus (anterior pillar)
- palatophryngeus (posterior pillar)
- musculus uvulae
- levator veli palatini
- tensor veli palatini
muscle of soft palate that approximates palate to tongue and narrows oropharyngeal opening
palatoglossus
muscle if soft palate that raises larynx and pharynx, closing oropharyngeal aperture
palatopharyngeus
muscles of soft palate that shortens uvula
musculus uvulae
muscle of soft palate that raises soft palate to contact posterior pharyngeal wall
levator veli palatini
muscle of soft palate that pulls soft palate laterally to give rigidity and firmness to palate
tensor veli palatini
muscle originates in part on the eustachian tube cartilage
contraction opens tube
tensor veli palatini
motor innervation of soft palate
V3 motor division—> pharyngeal plexus—>tensor veli palatini
X—>pharyngeal plexus—>remainder of palatal muscles
sensory innervation of soft palate
CN V2, IX, X
tonsillar pillar originate from the…
2nd and 3rd branchial arches
tonsillar crypts are 1st noted during…
12th week of gestation
capsule: 20th week
comprised of lymphoid tissue with geminal center containing 6 to 20 epithelial lined crypts
palatine tonsils
capsule of palatine tonsil is separated from the…
superior constrictor by thin areolar tissue
contiguous with the lymphoid tissue of the tongue base
palatine tonsil
arterial blood supply of palatine tonsil
- facial—>tonsillar branch—>tonsil
- facial—>ascending palatine—>tonsil
- lingual—>dorsal lingual—>tonsil
- ascending pharyngeal—>tonsil
- maxillary—>lesser descending palatine—>tonsil
lymphoid tissue within lip of fossa of Rosenmuller
gerlach’s tonsil
venous drainage of pharynx
- lingual vein
2. pharyngeal vein
oropharyngeal walls
- passavant’s ridge
- lateral pharyngeal bands
- muscles
visible constriction of superior end of superior constrictor where fibers of the palatopharyngeal constrictor interdigitate
seen during approximation of palate to posterior pharyngeal wall and during elevation of the pharynx during swallowing
passavant’s ridge
rests of lymphoid tissue just behind posterior pillars
lateral pharyngeal bands
pharyngeal constrictors
- superior constrictor
- middle constrictor
- inferior constrictor
pharyngeal constrictor
originates on the medial pterygoid plate, mandible, and base of tongue and inserts on median plane
superior constrictor
pharyngeal constrictor
originates on the hyoid bone and stylohyoid ligament
middle constrictor
pharyngeal constrictor
origin is on the oblique line of thyroid cartilage
inferior constrictor
pharyngeal and laryngeal elevators (shortens pharynx)
- salpingopharyngeus
- stylopharyngeus
- stylohyoid
pharyngeal and laryngeal elevators
origin is on the temporal bone and eustachian tube
salpingopharyngeus
pharyngeal and laryngeal elevators
origin is on the styloid process
- stylopharyngeus
2. stylohyoid
is the most inferior portion of inferior constrictor
separated from it by a triangular dehiscence termed Killian’s dehiscence
cricopharyngeus muscle
other dehiscence
between the posterior cricopharyngeus amd the esophageal musculature
Laimer-Haeckerman space
a lateral dehiscence inferior to the cricopharyngeus through which branches of the inferior thyrpid artery pass
Killian-Jamieson space
most basic function of larynx
airway protection
three phases of swallowing
- oral phase
- pharyngeal phase
- esophageal phase
prepares the food for delivery to the pharynx
oral phase
components of oral phase
- mastication
- addition and mixing of saliva
- control of bolus (tongie, lips, buccinator, palate)
- selection and verification of safety of bolus
oral phase
voluntary control
ends when the bolus is pressed against the faucial arches to precipitate the involuntary pharyngeal phase
trigger the involuntary pharyngeal swallow
preesure-sensitive receptors on anterior tonsillar pillar
moves the bolus quickly (less than 1 sec) past the closed glottis and through upper esophageal sphincter into the esophagus
pharyngeal phase
components of pharyngeal phase
- nasopharyngeal closure with palate elevation
- cessation of respiration (expiration)
- glottic closure
- bolus propulsion
- laryngeal elevation and pharyngeal shortening
- epiglottic rotation
- relaxation of cricopharyngeus muscle
conveys boluscto the stomach in an average of 3-6 seconds with primary peristalsis and relaxation of LES
esophageal phase