Study Guide – Salivary Glands & Oral Mucosa (Vocabulary Flashcards)

A comprehensive set of vocabulary flashcards covering major and minor salivary glands, cementum/alveolar bone/PDL anatomy, and the structure and function of the oral mucosa and related tissues as described in the notes.

Parotid gland

Major serous salivary gland; discharges into the oral cavity through Stensen’s duct.

Stensen’s duct

Duct through which the parotid gland releases saliva into the oral cavity.

Submandibular gland

Major salivary gland; mixed secretion, predominantly serous; secretions via Wharton’s duct.

Wharton’s duct

Duct that drains saliva from the submandibular gland into the oral cavity.

Sublingual gland

Major salivary gland with mixed secretions, mostly mucous.

Von Ebner’s gland

Serous minor salivary gland of the tongue.

Minor salivary glands

Glands on hard/soft palate, tongue, and lips; all mucous except von Ebner’s.

Acini

Glandular units that can be serous or mucous.

Serous acini

Acini formed by pyramidal cells surrounding a central lumen; basally located nucleus; secretory granules at apex.

Mucous acini

Tubular acini with a larger lumen; mucous apical material; nucleus flattened; may have serous demilunes.

Demilune (serous demilune)

Serous cap on mucous acini at the end of the tubule.

Myoepithelial cells

Contractile cells at the basal aspect of acini aiding saliva propulsion into ducts.

Intercellular canaliculi

Small spaces between acinar cells through which secretions reach the lumen.

Intercalated ducts

Smallest ducts; initial secretions; lined by low cuboidal epithelium; associated with myoepithelial cells.

Striated ducts

Ducts formed from merging intercalated ducts; lined by columnar epithelium with basal striations (mitochondria-rich).

Excretory intralobular ducts

Larger intralobular ducts that continue the duct system within a lobule.

Primary saliva

Initial saliva produced by acinar cells and intercalated ducts.

Secondary (modified) saliva

Primary saliva modified as it passes through striated and excretory ducts.

Rough endoplasmic reticulum (RER)

Organelle abundant in acinar cells; site of secretory protein synthesis.

Golgi complex

Organelle involved in protein modification, condensation, and packaging into secretory granules.

Secretory proteins

Proteins synthesized in acinar cells; undergo folding and post-translational modifications.

Chaperones

Molecules that assist proper folding of nascent secretory proteins.

Post-translational modifications

Processes such as disulfide bond formation and N- and O-linked glycosylation.

Secretory granules

Stored secretions in the apical cytoplasm released by exocytosis.

Norepinephrine

Sympathetic neurotransmitter that stimulates exocytosis in salivary glands.

Exocytosis

Process by which secretory granule contents are released from the cell into the lumen.

Lobules

Glandular units divided by connective tissue septa.

Connective tissue septa

Divide glands into numerous lobules, housing secretory units and ducts.

Intercalated ducts (overview)

Initial secretory ducts with small lumina, low cuboidal lining, partly surrounded by myoepithelium.

Striated ducts (overview)

Renowned for basal striations due to myoarchitectural mitochondria; columnar lining.

Pseudostratified columnar epithelium

Epithelium lining interlobular and interlobar ducts.

Interlobular ducts

Larger ducts formed by joining intralobular ducts; may be pseudostratified columnar.

Interlobar ducts

Even larger ducts; may be lined by stratified epithelium.

Cementum

Mineralized, avascular connective tissue covering the root dentin.

Cementoblasts

Cells located in the periodontal ligament space; responsible for cementum formation.

Cementoclasts

Cells responsible for resorbing cementum.

Cementocytes

Entrapped cementoblasts regulating cellular cementum formation and resorption.

Acellular extrinsic fibrous cementum (AEFC)

Primary cementum; forms cervical ⅔; anchors Sharpey’s fibers; no embedded cells.

Cellular intrinsic fibrous cementum (CIFC)

Secondary cementum; forms quickly; cementocytes present; attached to apical/interradicular regions.

Acellular afibrillar cementum

Cementum with no collagen fibers; deposited along CEJ and over enamel/dentin.

Cementoenamel junction (CEJ) types

Locations where cementum meets enamel: overlap (most common), edge-to-edge, or gap.

Overlaps enamel (CEJ type)

Cementum overlaps enamel; most common type (~60%).

Edge-to-edge (CEJ type)

Cementum meets enamel edge-to-edge.

Cementum–enamel gap (CEJ type)

Gap between cementum and enamel exposing dentin; can cause root sensitivity.

Alveolar bone proper (bundle bone / lamina dura)

Bone surrounding the tooth root; dense bone forming the socket wall.

Cortical plates

Outer compact bone plates (buccal/labial and palatal/lingual) of the jaws.

Trabecular (cancellous) bone

Sponge-like bone between cortical plates and alveolar bone proper.

Alveolar crest

Most coronal part of the alveolar process; located ~1–2 mm below CEJ.

Alveolar crest thickness (anatomy)

Thinner in maxilla/anterior, thickest on buccal of mandibular posterior teeth.

Periodontal ligament (PDL)

Soft connective tissue between cementum and alveolar bone proper; suspends tooth; nourishes cementum; sensory and proprioceptive function.

PDL fibroblasts

Most abundant cells in PDL; high protein turnover and maintenance of tissue.

Msx2

PDL-produced protein that helps prevent ankylosis.

PDL innervation

Two types: sensory (nociception and mechanoreception) and autonomic (vasomotor).

Sensory innervation (PDL)

Nociception and mechanoreception; myelinated fibers dominate; Ruffini-like endings as mechanoreceptors.

Autonomic innervation (PDL)

Sympathetic/parasympathetic supply to vessels and glands within the PDL region.

PDL principal fibers

Alveolar crestal, Horizontal, Oblique, Apical, Interradicular – attach cementum to bone and resist forces.

Alveolar crestal fiber

Extends obliquely from cementum below CEJ to alveolar crest; resists vertical lateral movement.

Horizontal fiber

Extends at right angles from cementum to alveolar bone; resists horizontal forces.

Oblique fiber

Largest group; extends obliquely from cementum to bone; resists vertical and intrusive forces.

Apical fiber

From root apex to bone; resists vertical forces.

Interradicular fibers

Between roots of multirooted teeth; resist vertical and lateral forces.

Gingival PDL fibers (gingival groups)

Trans-septal, Dento-gingival, Alveolo-gingival, Circular, Dento-periosteal – stabilize gingiva and tooth related to alveolar bone.

Trans-septal fibers

Extend interdentally from cementum over the alveolar bone crest to adjacent tooth cementum.

Dento-gingival fibers

From cervical cementum to lamina propria of free and attached gingiva.

Alveolo-gingival fibers

From alveolar crest to lamina propria of free/attached gingiva.

Circular fibers

Band around the neck of the tooth; interlace with other gingival fibers.

Dento-periosteal fibers

From cementum to periosteum of outer cortical plate.

Hypercementosis

Abnormally thickened cementum, often at root apex or interradicular areas.

Cementicle

Small globular mass of cementum in PDL; microtrauma; may be free or attached.

Cementoblastoma

Benign neoplasm producing cementum-like tissue anchored to a root apex.

Hypophosphatasia

Low activity of alkaline phosphatase; reduced cementum formation.

Oral mucosa

Epithelium + connective tissue; protective, sensory, and secretory functions.

Keratinized vs non-keratinized epithelium

Keratinized: surface layer of dead cells rich in keratin; non-keratinized: alive, flexible; parakeratinization can occur in oral mucosa.

Parakeratinization

Normal in oral mucosa; retained nuclei in the keratinized layer.

Fordyce’s spot

Sebaceous glands visible on the mucosa of the upper lip and buccal mucosa; absence of stratum lucidum.

Lamina propria

Connective tissue proper underlying epithelium; has papillary and reticular layers.

Lamina propria papillary layer

Superficial loose CT with interdigitation with epithelium (rete ridges).

Lamina propria reticular layer

Deeper, thicker, denser CT with larger blood vessels and nerves.

Basement membrane (BM)

Layered structure between epithelium and lamina propria; composed of lamina lucida, lamina densa, and laminin/integrin networks.

Lamina lucida

Clear, thin BM layer adjacent to basal cells.

Lamina densa

Dense BM layer with type IV collagen and laminins.

Lamina fibroreticularis

Fibrous connective tissue part of BM complex linking to underlying stroma.

Hemidesmosomes

Anchoring junctions connecting epithelial cells to BM via integrins (α6β4).

Integrins (α6, β4)

Transmembrane receptors mediating epithelial attachment to BM.

BP180 (collagen XVII)

Basement membrane antigen associated with bullous pemphigoid, part of hemidesmosome adhesion.

BP230 (plectin)

Bullectous pemphigoid-associated protein in hemidesmosomes.

Taste bud

Structure containing 50–150 taste receptor cells (TRCs) within a taste pore.

Taste receptor cells (TRCs)

Sensory cells in taste buds; include gustatory, sustentacular, and basal cells.

Gustatory cells

TRCs responsible for taste sensation.

Sustentacular cells

Supportive cells within taste buds.

Basal cells (taste buds)

Progenitor cells that divide to replace other TRCs.

Taste pore

Opening at the apical surface of a taste bud where microvilli extend.

Papillae (types)

Filiform (top, most numerous), Fungiform (anterior), Circumvallate (back, few), Foliate (sides).

Circumvallate papillae

Back of tongue; contain many taste buds; surrounded by trenches with von Ebner’s glands (serous).

Von Ebner’s glands

Serous minor salivary glands associated with circumvallate papillae; secrete into furrows around the papilla.

Taste buds distribution

Circumvallate, Foliate, and Fungiform papillae contain taste buds; Filiform lack taste buds.

Lingual tonsil

Lymphatic tissue on the posterior tongue.

Mucocutaneous junction

Interface between the skin and oral mucosa.

Mucogingival junction

Junction between alveolar/masticatory mucosa and gingival mucosa.

Dentogingival junction

Region where gingiva meets tooth; includes sulcular epithelium and junctional epithelium.