cleft

cleft (kleft) a fissure, especially one occurring during embryonic development.

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anal cleft  gluteal c.

branchial cleft 

1. any of the slitlike openings in the gills of fish, between the branchial arches.

2. pharyngeal groove.

facial cleft 

1. any of the clefts between the embryonic prominences that normally unite to form the face.

2. prosoposchisis; failure of union of a facial cleft, causing a developmental defect such as cleft cheek or lip.

gluteal cleft  that which separates the buttocks.

subneural clefts  evenly spaced lamella-like clefts within the primary synaptic cleft, formed by infoldings of the sarcolemma into the underlying muscle sarcolemma.

synaptic cleft 

1. a narrow extracellular cleft between the presynaptic and postsynaptic membranes.

2. synaptic trough.

visceral cleft  pharyngeal groove.

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cleft (klft)

n.

A split or fissure between two parts.

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cleft (kleft),

n a longitudinal fissure of opening.

cleft, facial,

n the fissures along the embryonal lines of the junction of the maxillary and lateral nasal processes; usually extend obliquely from the nasal ala to the outer border of the eye (canthus).

cleft, gingival,

n a cleft of the marginal gingiva; may be caused by many factors, such as incorrect toothbrushing, a breakthrough to the surface of pocket formation, or faulty tooth positions, and may resemble a V-shaped notch.

cleft lip,

n a congenital anomaly of the face caused by the failure of fusion between embryonic maxillary and medial nasal processes.

Cleft lip and palate.

cleft, occult,

n See submucous cleft.

cleft, operated,

n (postoperative cleft), a cleft that has been surgically repaired.

cleft palate,

n a congenital anomaly of the oral cavity caused by the failure of fusion between the embryonic palatal shelves.

cleft palate, alveolar graft,

n a bone graft placed at the site of a hard palate cleft before teeth have an opportunity to erupt through the gingiva tissue. It creates the architecture necessary for normal eruption of the maxillary teeth and provides support for adjacent teeth. It may also eliminate the need for prosthetic intervention in the future.

cleft palate, hard palate graft,

n a bone graft used to block the oronasal passage in order to facilitate breathing in children with hard palate clefts.

cleft palate prosthesis,

n See prosthesis, cleft palate.

cleft, postoperative,

n See cleft, operated.

cleft, Stillman's,

n the small fissures extending apically from the midline of the gingival margin in teeth subjected to trauma. Although these clefts may be found in traumatism, they are not necessarily diagnostic of occlusal trauma.

cleft, submucous,

n See submucous cleft.

cleft, unoperated,

n a cleft of the palate that has not been surgically repaired.

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cleft

a fissure or longitudinal opening, especially one occurring during embryonic development.

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branchial c's

the slit-like openings in the gills of fish between the branchial arches; also, the homologous branchial grooves between the branchial arches of mammalian embryos.

cleft chin

occasionally seen in cattle particularly Herefords. There is a notch at the mandibular symphysis and the central incisors may be directed centrally.

frog cleft

the sagittal cleft in the frog of the horse's foot.

glottic cleft

entrance to the larynx; called also rima glottidis.

infundibular cleft

common opening of the auditory tubes in birds.

interdigital cleft

separates the hooves.

cleft lip

a defect in fusion between the central prolabium and one or both lateral mesodermal masses. Most common in dogs of the brachycephalic breeds; may be inherited or caused by environmental factors. Often combined with defects in the palate. Called also primary cleft palate, harelip, cheiloschisis.

Congenital fissure, or split, may involve the hard or soft palate. A common cause of nasal regurgitation in neonates, especially foals. Known to be inherited in some breeds of cattle and dogs, particularly brachycephalic breeds. Called also secondary cleft palate, palatoschisis.

Cleft lip (harelip) in a calf. By permission from Blowey RW, Weaver AD, Diseases and Disorders of Cattle, Mosby, 1997

cleft palate

see cleft lip (above). Also occurs commonly in diseases manifest with arthrogryposis, both hereditary as in Charolais cattle and with lupine-induced crooked calf.

Rathke cleft

see rathke's pouch.

cleft tongue

the anterior portion is divided by a longitudinal cleft.

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Rathke's pouch, cleft, pocket

a diverticulum from the embryonic buccal cavity from which the anterior pituitary is developed.

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Rathke's pouch pouch cyst

failure of the ectoderm of Rathke's pouch to differentiate into adenohypophyseal tissue. A cyst fills the space normally occupied by the pituitary gland and the animal is a dwarf with panhypopituitarism.