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Flashcards in Congenital Defects Deck (13)
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Clefts are ___% of all congenital malformations


*2nd most common malformation


Oblique facial-

Median cleft lip-

Bilateral cleft lip-

Failure to fuse maxillary lateral nasal process.

Failure to fuse median nasal process.

Failure to fuse maxillary medial nasal process.


Environmental (2 pts)

Presence of teratogens
Timing of the teratogens

*more from environment

*Lips- 4-6wks
Tongue- 4-8wks
1st arch- 4-10wks


Cleft etiologies:

Primary palate-

Clefts maybe isolated or with clefts of secondary palate


Deficiency in mesenchyme: (2 pts)

Failure of neural crest cells to migrate

Failure of mesenchyme to proliferate


Isolated palatal celts:

Mechanisms (4)

1. Failure of shelves to contract

2. No fusion of shelves (epithelium not resorbed)

3. Rupture after fusion

4. Defective merging/consolidation of mesenchyme

*using suction feels like their breath is being taken away


Palatal cleft: dental influences

Unilateral primary palatal cleft-

Bilateral primary cleft palate-

If associated with secondary palatal cleft-

Missing incisors, teeth 7/8 or 9/10

All incisors missing (7-10) canines could be involved (2nd palate)

Premolars and molars are okay, but incisors and canines gone


Unilateral primary cleft palate:

*teeth ____ and _____

9 and 10

Lip involved

*did not have fusion of 2nd palate


Unilateral primary and 2ndary cleft palates:

*2ndary palate didn't fuse with premaxilla

*can see nasal cavity


Bilateral primary cleft palate:

*primary didn't come down

*can see nasal septum


Bilateral primary and 2ndary cleft palates:

*no teeth from anteriors forward

*can have premolars and molars


Cleft tongue:

Lingual swellings fail to

Partial cleft results in

Either a failure of _________ or ________ to proliferate

Merge together

Deep groove

Epithelial cells to die or mesenchymal cells

*recommend tongue scraper


Treacher-Collins syndrome:

Failure of

Neural crest cells to migrate to the facial region