Oral cavity and Exocrine Glands

LECTURE 5

what is the oral vestibule

the area between the lips and cheek and the teeth and gums

what is oral cavity proper?

space posterior and medial to the upper an dlower dental arches

what forms the roof of oral cavity proper (OCP) ?

• hard palate

• soft palte

what forms the walls of OCP?

alveolar bone of jaws

what forms the floor of OCP?

anterior 2/3 of the tongue

what is the frenulum and what lies on either side of it?

mucous membrane fold under the tongue, with an opening on either side of it of the submandibular gland. there is also the sublingual folds and ducts on either side.

what are the muscles of the lips and cheeks?

• orbicularis oris

• buccinator

what innervates the regions of skin and oral mucosa of the lips and cheek

• top lip: superior labial branch → infraorbital nerve CNV1

• cheeks: buccal branch → mandibular nerve CNV3

• lower lip: inferior labial branch → mental nerve

what provides sensation to the tongue and mucous membranes?

most sensory innervation comes from CN V except taste sensation to tongue is from Chorda Tympani nerve (CN VII)

what innervates the hard and soft palates?

the greater palatine and nasopalatine nerves of CNV3

glossopharyngeal nerve sensory of soft palate.

what bones form the hard palate?

• palatine process of maxilla

• horizontal plate of the palatine bones

what forms the soft palate?

5 muscles converge from above and below and descend onto the palate. connects to the hard palate via aponeurosis.

what nerve supplies the oral cavity and gteeth?

the trigeminal nerve CNV2 CNV3

what is the function of the muscles of the tongue?

• speech

• chewing

• swallowing

• taste

• oral cleansing

where does the root of the tongue attach?

the hyoid bone

what is the terminal sulcus and what does it do?

it is a v shaped groove with divides the tongue into:

• pre-sulcal → anterior 2/3

• post-sulcal → pharynx

what is the function of the lingual septum?

separates the intrinsic and extrinsic muscles in each half of the tongue

what is the action of the genioglossus

• depresses

• retracts

• wags

what is the action of the hyoglossus?

• depresses

• draws side down

what is the action of the styloglossus

• retracts

• elevates (curls sides)

what is the action of the palatoglossus?

• elevates posterior tongue

• depresses soft palate

what provides motor innervation to the tongue

hypoglossal nerve CNXII except palatoglossus (CNX)

what is the innervation for the anterior 2/3 of the tongue?

normal sensation → lingual nerve CNV

taste → chorda tympani CNVII

what provides sensory innervation to the postsulcal tongue?

glossopharyngeal nerve CNIX

what is the function of the lacrimal glands?

secretes lacrimal fluid (tears) onto the conjunctiva onto the eye. it drains into the lacrimal sac → nasolacrimal duct.

what provides secretomotor innervation to the lacrimal glands?

greater petrosal nerve CNVII → pterygopaltine ganglion → joins zygomatic nerve → stimulates lacrimation

what are the smallest salivary glands?

sublingual glands

describe the location of the sublingual glands

on the floor of oral cavity proper beneath sublingual glands. lies between genioglossus (medially) and mylohyoid (laterally)

describe the location of the superficial and dep arms of the submandibular glands

• superficial: outside the boundary of the oral cavity, below mandible

• deep: hooks around the posterior margin of the mylohyoid muscle

what is the name of the duct that carries secretions of the submandibular gland?

wharton’s duct - 5 cm long

what is t secretomotor innervation of the sublingual and submandibular glands?

chorda tympani nerve CNVII (submandibular ganglion)

what provides sensory innervation to the sublingual and submandibular glands?

lingual branch of mandibular nerve

what pierces through the buccinator muscle?

parotid duct of the parotid gland

what provides secretomotor innervation to the parotid glands?

glossopharyngeal nerve

what can cause hypoglossal nerve palsy?

trauma such as fracture mandible

how does hypoglossal nerve palsy present?

paralysis and atrophy of the tongue

deviates towards paralysed side.

what is sialography

injection of contrast medium for

screening of salivary gland obstructio