Editing Oral mucosa

{{Infobox anatomy
| Name         = Oral mucosa
| Latin        = Tunica mucosa oris
| Image        = 
| Caption      = Histological cross-section showing the epithelium, basement membrane, and lamina propria.
| System       = [[Exocrine system]], [[Digestive system]]
| Component    = [[Stratified squamous epithelium]], [[Lamina propria]]
}}

==Definition==
The '''oral mucosa''' is the mucous membrane lining the inside of the [[oral cavity]]. It consists of '''[[stratified squamous epithelium]]''' and an underlying connective tissue called the '''[[lamina propria]]'''. In certain areas, it is supported by a deeper '''submucosa'''.

The oral mucosa serves as a primary barrier against mechanical trauma, microorganisms, and toxic substances, while also providing sensory information (touch, temperature, and [[taste]]).

==Classification by Function==
The oral cavity is not uniform; the mucosa is specialized based on the mechanical stress it endures:

===1. Masticatory Mucosa===
This mucosa is designed to withstand the forces of [[mastication]] (chewing). It is typically '''keratinized''' or '''parakeratinized'''.
* '''Locations''': [[Hard palate]] and [[Attached gingiva]].
* '''Characteristics''': Firmly bound to the underlying bone (mucoperiosteum); lacks a submucosa in most areas.

===2. Lining Mucosa===
The most common type, providing flexibility for speech and swallowing. It is '''non-keratinized'''.
* '''Locations''': [[Buccal mucosa]] (cheeks), [[labial mucosa]] (lips), [[floor of the mouth]], ventral surface of the [[tongue]], and [[soft palate]].
* '''Characteristics''': Soft, moist, and elastic; usually has a well-developed submucosa containing [[minor salivary glands]].

===3. Specialized Mucosa===
Found specifically on the dorsal (top) surface of the '''[[tongue]]'''.
* '''Characteristics''': Contains both keratinized and non-keratinized areas and is characterized by the presence of '''[[lingual papillae]]''' and '''[[taste buds]]'''.

==Microscopic Structure==
The oral mucosa is composed of several distinct layers:
# '''Epithelium''': Stratified squamous type. It can be orthokeratinized (no nuclei in the top layer), parakeratinized (shrunken nuclei present), or non-keratinized.
# '''Basement Membrane''': The interface between the epithelium and connective tissue.
# '''Lamina Propria''': A layer of connective tissue containing blood vessels, nerves, and collagen fibers. It is divided into the papillary layer and the reticular layer.
# '''Submucosa''' (where present): Contains larger blood vessels, nerves, and adipose tissue or salivary glands.

==Clinical Significance==
* '''[[Permeability]]''': The lining mucosa (especially under the tongue) is highly permeable, allowing for '''sublingual administration''' of medications (e.g., nitroglycerin).
* '''[[Fordyce granules]]''': Ectopic sebaceous glands commonly found in the buccal mucosa; considered a variation of normal.
* '''[[Lineal alba]]''': A white line on the buccal mucosa caused by frictional keratinization from the teeth.
* '''[[Oral Lichen Planus]]''': A common chronic inflammatory condition affecting the oral mucosa.

==See Also==
* [[Gingiva]]
* [[Keratinization]]
* [[Saliva]]
* [[Oral Pathology]]

[[Category:Anatomy]]
[[Category:Histology]]
[[Category:Oral Biology]]