Cusp

In reference to heart valves, one of the triangular segments of the valve which opens and closes with the flow of blood. In reference to teeth, a raised area of the biting surface.

* * *

1. In dentistry, a conical elevation arising on the surface of a tooth from an independent calcification center. SEE ALSO: dental tubercle. 2. A leaflet of one of the heart's valves. SYN: cuspis [TA]. [L. cuspis, point]

- anterior c. of left atrioventricular valve anterior c. of mitral valve.

- anterior c. of mitral valve [TA] the ventrally placed and larger of the two leaflets that come together during ventricular systole to close the left atrioventricular orifice; it attaches to the septal aspect of the orifice. SYN: cuspis anterior valvae atrioventricularis sinistrae [TA], anterior c. of left atrioventricular valve, cuspis anterior valvae mitralis.

- anterior c. of right atrioventricular valve anterior c. of tricuspid valve.

- anterior c. of tricuspid valve [TA] the largest and most ventrally placed of the three leaflets that come together during ventricular systole to close the right atrioventricular orifice. SYN: cuspis anterior valvae atrioventricularis dextrae [TA], anterior c. of right atrioventricular valve, cuspis anterior valvae tricuspidalis.

- c. of Carabelli a fifth c. found on the maxillary first molars, usually located lingual to the mesiolingual c..

- posterior c. of left atrioventricular valve posterior c. of mitral valve.

- posterior c. of mitral valve [TA] the dorsally placed and smaller of the two leaflets that come together during ventricular systole to close the left atrioventricular orifice; it attaches to the mural aspect of the orifice. SYN: cuspis posterior valvae atrioventricularis sinistrae [TA], cuspis posterior valvae mitralis, posterior c. of left atrioventricular valve.

- posterior c. of right atrioventricular valve posterior c. of tricuspid valve.

- posterior c. of tricuspid valve [TA] the medium-sized and most dorsally placed of the three leaflets that come together during ventricular systole to close the right atrioventricular orifice. SYN: cuspis posterior valvae atrioventricularis dextrae [TA], cuspis posterior valvae tricuspidalis, posterior c. of right atrioventricular valve.

- semilunar c. one of the three semilunar segments serving as the three cusps of a valve preventing regurgitation at the beginning of the aorta; a similar valve guards the entrance of the pulmonary trunk; the segments are named, respectively, anterior, right, and left in the pulmonary valve, and posterior, right, and left in the aortic valve.

- septal c. of right atrioventricular valve septal c. of tricuspid valve.

- septal c. of tricuspid valve [TA] the leaflet of the tricuspid valve located adjacent to the interventricular septum. SYN: cuspis septalis valvae atrioventricularis dextrae [TA], cuspis septalis valvae tricuspidalis, septal c. of right atrioventricular valve.

- talon c. an anomalous c. that projects lingually from the cingulum of permanent incisors. [Eng. claw, heel, fr. O.Fr., fr. L. talus, ankle]

- c. of tooth [TA] an elevation or mound on the crown of a tooth making up a part of the occlusal surface. SYN: cuspis dentis [TA], cuspis coronae.

* * *

cusp 'kəsp n

1) a point on the grinding surface of a tooth

2) a fold or flap of a cardiac valve

cus·pal 'kəs-pəl adj

* * *

n.

1. any of the cone-shaped prominences on teeth, especially the molars and premolars.

2. a pocket or fold of the membrane (endocardium) lining the heart or of the layer of the wall of a vein, several of which form a valve. When the blood flows backwards the cusps fill up and become distended, so closing the valve.

* * *

(kusp) [L. cuspis point] 1. a tapering projection; see cuspis and valvula. 2. cuspis dentis.

Cusps of the heart valves.