2 Oral Cavity

Stratified squamous epithelium

The oral cavity consists of what tissue type?

Masticatory mucosa

The keratinized cell layers resist most damage from abrasion and become best developed in the?

Nonkeratinized squamous epithelium

Predominates in the lining mucosa over the soft palate, cheeks, the floor of the mouth, and the oral pharynx (or throat), the posterior region of the oral cavity leading to the esophagus.

Lips or labia

Represents the transition from oral mucosa to skin. Moistened with saliva by the tongue, this lip region lacks salivary and sweat glands

The red vermillion zone is composed of very thin keratinized stratified squamous epithelium rich in sensory innervation and capillaries. Thus a pink color is easily imparted.

Rationale behind the color of the lips

Tongue

Forms as a mass of striated muscle covered by mucosa, which can manipulate ingested material during mastication and swallowing.

All directions

Which directions do the fascicles of muscle fibers in the tongue develop, allowing a high level of mobility?

Papillae; massed lingual tonsils

The irregular dorsal surface has hundreds of small protruding ________of various types on its anterior two-thirds and the _____ on the posterior third, or root of the tongue

Sulcus terminalis

Demarcates the papillary and tonsillar areas of the tongue’s dorsal surface.

Hard Palate

Thin horizontal bony plate located in the roof of the mouth that separates the oral and nasal cavities

Lingual tonsils

On tongue’s dorsal surface the posterior third of the tongue produces what?

Lingual papillae

On tongue’s anterior surface the posterior third of the tongue produces what?

Filiform Papillae

Have elongated conical shapes and are very numerous and heavily keratinized, which can give this lingual surface a whitish appearance.

Fungiform Papillae

Much less numerous, interspersed among the filiform papillae, and lightly keratinized

Foliate Papillae

Consist of several parallel ridges on each side of the tongue, anterior to the sulcus terminalis, but are rudimentary in humans, especially older individuals.

Vallate or circumvallate Papillae

The largest papillae, lightly keratinized with diameters of 1–3 mm.

Salivary (von Ebner) Glands

Empty into the deep, moat-like groove that surrounds each vallate papilla.

Taste Buds

Develop as ovoid structures within the stratified epithelium on the tongue’s surface, and continuously sample the general composition of ingested material

250 taste buds

Approximately how many taste buds occur on the lateral suface of each vallate papillae?

Gustatory (Taste) Cells

A taste bud has 50–100 cells, about half of which consist of elongated ______.

Supportive Cells

Slender cells of taste buds

Taste Pore

At the apical ends of the gustatory cells, microvilli project toward a 2-μm-wide opening in the structure called the _____

32

How many permanent teeth does a human have?

8 teeth

Each quadrant has how many teeth?

two incisors, one canine, two premolars, and three permanent molars

Each quadrant consist of what teeth?

primary teeth

Twenty of the permanent teeth are preceded by ______ (deciduous or milk teeth) that undergo loss

Dental alveoli

Each tooth fit firmly into bony sockets called?

Enamel

Covers the crown

Cementum

Bone like tissue covering the roots

Dentin

The bulk of a tooth consists of another calcified material called _____

Dental Pulp

highly vascular, well-innervated, and composed largely of loose, mesenchymal connective tissue with much ground substance, thin collagen fibers, fibroblasts, and mesenchymal stem cells

Apical foramen

Located at the root’s tip for passage of the blood vessels, lymphatics, and nerves serving the pulp cavity.

Dentin

calcified tissue harder than bone, consisting of 70% hydroxyapatite

Odontoblasts

Tall cells derived from the cranial neural crest, which form a lining of the pulp cavity

Ameloblasts

In a developing tooth bud, the unmineralized matrix for the enamel rods is secreted by tall, polarized cells called what?

Ameloblast or Tomes process

contains numerous secretory granules with the proteins of the enamel matrix.

Amelogenin

main structural protein of developing enamel, initiates and guides growth of hydroxyapatite crystals within elongating enamel rods.

Periodontium

Comprises the structures responsible for maintaining the teeth in the maxillary and mandibular bones,

Cementum

covers the dentin of the root and resembles bone, but is avascular