- A stone, as in the urinary tract. Also, the calcium salt deposits on the teeth. The word "calculus" in Latin means "a pebble." Pebbles were once used for counting, from which came the mathematical field of calculus. A urinary calculus is a pebble in the urinary system.
* * *A concretion formed in any part of the body, most commonly in the passages of the biliary and urinary tracts; usually composed of salts of inorganic or organic acids, or of other material such as cholesterol. SYN: stone (1). [L. a pebble, a c.]- branched c. SYN: staghorn c..- coral c. SYN: staghorn c..- dendritic c. SYN: staghorn c..- dental c. 1. calcified deposits formed around the teeth; may appear as subgingival or supragingival c.; 2. SYN: tartar (2).- encysted c. a urinary c. enclosed in a sac developed from the wall of the bladder. SYN: pocketed c..- hematogenetic c. SYN: serumal c. (1).- matrix c. a yellowish-white to light tan urinary c. containing calcium salts, with the consistency of putty; composed chiefly of an organic matrix consisting of a mucoprotein and a sulfated mucopolysaccharide, and usually associated with chronic infection.- metabolic c. a stone, usually a renal stone, caused by a metabolic abnormality resulting in increased excretion of a substance of low solubility in urine, such as urate or cystine.- mulberry c. a hard nodular urinary c. composed of calcium oxalate, so-called because of its resemblance to a mulberry.- oxalate c. a hard urinary c. of calcium oxalate; some are covered with minute sharp spines that can abrade the renal pelvic epithelium, whereas others are smooth.- pancreatic c. a concretion, usually multiple, in the pancreatic duct, associated with chronic pancreatitis. SYN: pancreatolith, pancreolith.- pocketed c. SYN: encysted c..- primary renal c. a c. formed in an apparently healthy urinary tract, usually composed of oxalates, urates, or cystine.- prostatic c. a concretion formed in the prostate gland, composed chiefly of calcium carbonate and phosphate (corpora amylacea). SYN: prostatolith.- secondary renal c. a c. associated with infection and/or obstruction, usually composed of struvite (magnesium ammonium phosphate). SYN: infection c..- serumal c. 1. a greenish or dark brown calcareous deposit on the tooth, usually apical to the gingival margin; SYN: hematogenetic c.. 2. SYN: subgingival c..- staghorn c. a c. occurring in the renal pelvis, with branches extending into the infundibula and calices. SYN: branched c., coral c., dendritic c..- struvite c. a c. in which the crystalloid component consists of magnesium ammonium phosphate; usually associated with urinary tract infection caused by urease-producing bacteria.- subgingival c. calcareous deposit found on the tooth apical to the gingival margin. SYN: serumal c. (2).- supragingival c. calcified plaques adherent to tooth surfaces coronal to the free gingival margin.- tonsillar c. SYN: tonsillolith.- urethral c. a stone impacted in urethra. May have formed proximally and become stuck there or may have formed in urethra; uncommon.
* * *1) a concretion usu. of mineral salts around organic material found esp. in hollow organs or ducts2) a concretion on teeth: TARTAR
* * *n. (pl. calculi)1. a stone: a hard pebble-like mass formed within the body, particularly in the gall bladder (see gallstone) or anywhere in the urinary tract (see cystolithiasis, nephrolithiasis, staghorn calculus). Calculi in the urinary tract are commonly composed of calcium oxalate and are usually visible on X-ray examination. Some of these stones cause pain if they cause obstruction and prevent urine flow in the ureter or kidney, or by direct irritation of the bladder. Stones passing down a duct (such as the ureter) cause severe colicky pain. Most stones pass spontaneously, but some need to be broken into smaller pieces, usually by extracorporeal lithotripsy, and the remainder by endosurgical techniques (see litholapaxy) or rarely by open surgery. Calculi may also occur in the ducts of the salivary glands.2. a calcified deposit that forms on the surface of a tooth as it is covered with dental plaque. Supragingival calculus forms above the gingiva (gums), principally in relation to the openings of the salivary gland ducts. Subgingival calculus forms beneath the crest of the gingivae. Calculus hinders the cleaning of teeth and its presence contributes to gingivitis and periodontal disease.
* * *cal·cu·lus (kalґku-ləs) pl. calґculi [L. â€œpebbleâ€] an abnormal concretion in the body, usually composed of mineral salts. Called also stone. calculous adj
Medical dictionary. 2011.