- space between the lips and cheeks and dental arches

- bordered by the buccinator muscle

Vestibule

- bounded by the teeth, tongue, palate, fauces, oropharynx and floor of mouth

oral cavity proper

- largest of the major salivary glands

- located in the infratemporal region

- drain via Stenson's ducts

Parotid gland

- located in submandibular triangle of neck

- drain via Wharton's ducts

Submandibular glands

- located in floor of mouth (folds)

- drain via numerous small ducts or submandibular

Sublingual gland

- located in the submucosa throughout the oral cavity

- "buccal", "labial", "lingual"

Minor salivary glands

- covers gingiva and hard palate

- (para)keratinized stratified squamous epithelium

- lamina propria has papillary and reticular layer

Masticatory mucosa

- surface cells that don't lose their nuclei but do not have stratum granulosum (pyknotic)

Parakeratinized

- where the mucosa attaches directly to the periosteum of the underlying bone without the submucosa

- Ex: midline of hard palate, attached gingiva

Mucoperiosteum

- contains adipose, mucous glands, and collagen fibers

- can be present in hard palate

Submucosa

- found in lips, cheeks, floor of mouth, inferior surface of tongue, soft palate, alveolar mucosal surfaces

- covers muscle, bone and glands

- non-keratinized

Lining mucosa

- layered stratum basale, spinosum, intermedium, superficale

- contains keratinocytes, Langerhans' cells, melanocytes and Merkels' cells

Epithelium

- lining musosa's lamina propria contains vessels, nerves and these structures

Papillae

- can contain minor salivary glands and occasional sebaceous glands (Fordyce spots)

Submucosa of lining mucosa

- smallest and most numerous papillae

- conical, elongated

- CT core, keratinized strat squa epithelium

- no taste buds

- cover entire surface of tongue in rows pointing backward

Filiform papillae

- mushroom-shaped

- scattered among filiform, visible to naked eye

- most abundant near tip of tongue

- contain taste buds

Fungiform papillae

- largest, dome-shaped, 8-12 in number

- located just anterior to sulcus terminalis

- surrounded by a "moat", containing numerous taste buds

- ducts of von Ebner's glands (lingual salivary) empty into moat to flush them out

Circumvallate papillae

- located on parallel ridges separated by deep clefts

- along lateral edge of tongue

- harder to identify in older people

- contain numerous taste buds

serous glands empty into clefts

Foliate papillae

- taste pore located at apex of taste bud

- contain neuroepithelial or sensory cells, supporting, and basal cells

- oval pale-staining bodies

Taste Buds

- elongated and extends from base to taste pore

- attached to neighboring taste cells by tight junctions

- synapse with sensory neurons (VII, IX, X) at base

- turnover time ~ 10 days

Neuroepithelial or sensory cells

- less numerous than sensory cells

- extend from base to taste pore

- contain microvilli on apical surface

(connected by tight junctions)

- do not synapse with sensory neurons

- turnover time ~ 10 days

Supporting cells

- stem cells for the other two cell types of taste buds

Basal cells

- teeth are embedded in these processes of maxilla and mandible

Alveolar

- portion of tooth covered by enamel

- clinical crown (above gumline)

- anatomical crown (all tooth covered by enamel)

Crown

- portion of tooth located within tooth socket/alveolus

- outer surface covered by cementum

- can have one or multiple of these

Tooth Root

- acellular (cannot be remodeled or replaced, translucent)

- most highly mineralized structure in the body (96-98%)

- formed of rods ("keyhole" shaped) which span its full thickness

- integrity maintained by saliva, eroded by acid

Enamel

- secretes enamel

- derived from embryonic oral ectoderm

- originates from the enamel organ (outgrowth of oral ectoderm)

Ameloblasts

- lies deep to enamel, forms majority of tooth

- collagen-based, calcified tissue (70% hydroxyapatite)

- secreted by odontoblasts

- laid down in the form of tubules (odontoblast process) which extends to the dentinoenamel junction

Dentin

- unmineralized dentin that covers the pulpal surface of dentin (similar to osteoid)

- contains DPP and DSP (phospho/sialoprotein)

- becomes yellowish in color

Pre-dentin

- covers the outer surface of the root

- serves as attachment of periodontal ligament

- secreted by cemetoblasts

- 65% mineralized

- acellular except molar/pre-molars top 1/3

Cementum

- located in the pulp chamber

- formed of richly vascularized and innervated loose CT

- odontoblast layer covering the deep surface of dentin is considered part of this

Pulp

- serves as other attachment for periodontal ligament (sharpey's fibers)

- lines tooth socket

Alveolar bone

- attaches tooth root (cementum) to alveolus

- acts as shock absorber

- proprioceptive

- involved in tooth eruption and bone remodeling

- made of bundles of collagen fibers

Periodontal ligament (PDL)

- mucosa covering the oral surface of alveolar bone

- portion attaching to the root of the tooth is called junctional epithelium (prone to inflammation)

Gingiva ("gums")

- CT surrounding salivary glands, forms septa, divides gland into lobes and lobules

- minor salivary glands don't have this

- lymphocytes, plasma cells present

Capsule of major salivary glands

- blind-ended sac whose walls are secretory cells (serous and/or mucous)

- a mixed one of these consists of mucus cells surrounded by a serous demilune

Salivary Acini

- pyramid-shaped

- large amounts of RER, free ribosomes, Golgi, secretory granules (zymogen) located apically

- base stains dark, apex stains lighter

- joined apically, basal folding

Serous cells

- stores mucinogen granules (empty staining)

- organelles found in basal part of cell

- nucleus flattened against base

- cells joined by apical junctional complexes

Mucous cells

- contractile cells with numerous processes

- between epithelial cells and basal lamina

- surround proximal portion of the duct system

Myoepithelial cells

- ducts that begin within acini

- lined by low cuboidal epithelium

- most prominent serous glands

- secrete bicarb, absorb chloride

Intercalated ducts

- lined by simple cuboidal cells transitioning to simple columnar

- basal infoldings --> striations

- centrally located nuclei

- reabsorb Na, Secrete K and HCO3

- make secondary saliva is hypotonic

Striated ducts

- principal ducts of salivary glands

- drain to oral cavity

- simple cuboidal -->columnar-->stratified cuboidal --> stratified columnar

Excretory ducts

- 1200 ml/day

- wets oral mucosa

- moistens foods

- dissolves food materials to stimulate taste buds

- buffers oral cavity contents

- digests carbs/controls bacteria (lyzozyme)

- contains IgA

Saliva