plaque

plaque (plak)

1. any patch or flat area.

2. a superficial, solid, elevated skin lesion.

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attachment plaques  small regions of increased density along the sarcolemma of skeletal muscles to which myofilaments seem to attach.

bacterial plaque , dental plaque a soft thin film of food debris, mucin, and dead epithelial cells on the teeth, providing the medium for bacterial growth. It contains calcium, phosphorus, and other salts, polysaccharides, proteins, carbohydrates, and lipids, and plays a role in the development of caries, dental calculus, and periodontal and gingival diseases.

fibrous plaque  the lesion of atherosclerosis, a pearly white area within an artery that causes the intimal surface to bulge into the lumen; it is composed of lipid, cell debris, smooth muscle cells, collagen, and, in older persons, calcium.

Hollenhorst plaques  atheromatous emboli containing cholesterol crystals in the retinal arterioles, a sign of impending serious cardiovascular disease.

senile plaques  microscopic argyrophilic masses composed of fragmented axon terminals and dendrites surrounding a core of amyloid, seen in small amounts in the cerebral cortex of healthy elderly people and in larger amounts in those with Alzheimer's disease.

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plaque (plk)

n.

1. A small disk-shaped formation or growth; a patch.

2. A deposit of fatty material on the inner lining of an arterial wall, characteristic of atherosclerosis.

3. Dental plaque.

4. A clear, often round patch of lysed cells in an otherwise opaque layer of a bacteria or cell culture.

5. A scaly patch formed on the skin by psoriasis.

6. A sharply defined zone of demyelination characteristic of multiple sclerosis.

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Plaque

Patches of scar tissue that form where the layer of yelin covering the nerve fibers is destroyed by the multiple sclerosis disease process.

Mentioned in: Angiography, Angioplasty, Atherosclerosis, Cholesterol Test, Coronary Artery Disease, Heart Attack, Ischemia, Multiple Sclerosis, Oral Hygiene, Peripheral Vascular Disease, Tooth Decay

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plaque

[plak]

Etymology: Fr, plate

1 a flat, often raised patch on the skin or any other organ of the body.

2 a patch of atherosclerosis.

3 also called bacterial plaque, a usually thin film on the teeth. It is made up of mucin and colloidal material found in saliva and often secondarily invaded by bacteria.

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plaque (dental) (plak),

n 1. in dentistry, a biofilm noted in the oral cavity. It consists of salivary proteins, microorganisms, and other byproducts of the microorganism. A type of intercellular matrix is also present. It forms on the oral cavity surface after the formation of the salivary pellicle using selective attachment factors. It is a factor in initiation and continuation of dental caries and periodontal disease. Older terms:
mucin plaque, bacterial plaque. 2. deposits of cholesterol in the arteries, possibly causing disease.

plaque, cocci in

n.pl the gram-positive microorganisms occurring in early-developing plaque that are later replaced with filaments as the plaque matures.

plaque, epithelium-associated,

n the loosely attached subgingival plaque found in the epithelium of the periodontal pocket that consists of gram-negative microorganisms and white blood cells.

plaque, fissure,

n a plaque that develops in the pit and fissures of a tooth.

plaque, pigmented dental,

n a colored plaque that is not related to the development of gingivitis and is often found in oral cavities that are almost plaque free. The plaque may be colonized by pigment-producing bacteria. The condition may be controlled by diligent plaque removal, but reoccurrence is possible. Also called
black line stain.

plaque, subgingival,

n a thick, noncalcified mass of plaque situated inferior to the gingival margin. It may or may not be attached to the epithelium or tooth and may cover subgingival calculus. It cannot be removed with flow of saliva or water. It can calcify with minerals from the lamina propria's blood vessels and become subgingival calculus.

plaque, supragingival

n a thick, noncalcified mass of plaque superior to the gingival margin. It cannot be removed with flow of saliva or water. It may or may not cover supragingival calculus. It may appear on any surface in the oral cavity. It can calcify from salivary minerals and become supragingival calculus. It can be stained with disclosing solutions. See also disclosing solution.

Supragingival plaque.

plaque, tooth-surface-attached,

n a type of subgingival plaque that uses selective attachment factors and is located in the subgingival area. This type of plaque is implicated in the formation of caries of the root and eventual breakdown of the root (resorption).

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plaque

1. any patch or flat area.

2. a clear area of cell lysis caused by viral replication on a cell monolayer.

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amniotic plaque

small, 1 to 2 inch diameter, poxlike lesion on the inside of the amnion. Constant on the bovine amnion during the middle trimester and causes no problems.

annular plaque

seen in equine lupus erythematosus panniculitis.

plaque assay

a method of quantifying the number of infectious units by inoculating serial dilutions of a viral suspension on a cell culture monolayer, overlaying with a medium containing agarose and after several days incubation, counting the number of plaques formed; recorded as plaque forming units/ml.

atheromatous plaque

a deposit of predominantly fatty material in the lining of blood vessels occurring in atherosclerosis.

bacterial plaque, dental plaque

a mass adhering to the enamel surface of a tooth, composed of a mixed colony of bacteria in an intercellular matrix of bacterial and salivary polymers and remnants of epithelial cells and leukocytes. It may cause caries, dental calculi and periodontal disease.

cutaneous plaque

an elevated, solid structure without a necrotic center, up to 1 to 2 inch diameter with an unbroken surface.

drug plaque

cutaneous, subcutaneous or subconjunctival deposits formed as a result of injection of some drugs, particularly repository steroid preparations. May be unsightly and a cause of conjunctivitis.

ear plaque

see ear plaque.

eosinophilic plaque

see eosinophilic plaque.

plaque-forming cells

see plaque assay (above).

plaque-forming count

the number of plaques formed in the plaque assay.

senile plaque

described in the brain of old dogs.

siderotic plaque

nodules observed as dry, yellow encrustations on the splenic capsule of old dogs.

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plaque

Cardiology An early lesion of ASHD found in persons of any age in larger vessels Dentistry A soft sticky substance on teeth composed of bacteria and saliva; an indurated gob of polysaccharides and bacteria–eg, Lactobacillus acidophilus, Streptococcus mutans. See Periodontitis Dermatology A flat, solid, elevated ≥ 1.0 cm in diameter skin nodule formed either by extension or coalescence of papules of lichen amyloidosis, lichen simplex chronicus, lichen planus, psoriasis; a 'plaque' stage occurs in certain skin tumors–eg, the 2^nd stages of KS, mycosis fungoides Neurology 'Shadow plaques' Multiple, irregularly shaped, and sharply demarcated lesions–focal demyelinization in the gray and white matter in the brain of Pts with MS. Asymmetric unit membrane plaque, Atherosclerotic plaque, Complicated plaque, Fibrous plaque, Multiple sclerosis, Parietal pleural plaque, Senile plaque, Shadow plaque, Soldier's plaque