abnormal craniofacial development

Question 1

What are craniofacial malformations?

Answer 1

Any congenital abnormalities of the head that interferes w physical and mental well being

3% of births have an identified anomaly

Question 2

How are abnormalities classified?

Answer 2

Embryological defects- evident at birth but can worsen w growth, if severe may be incompatible w life

Developmental defects- may not be immediately apparent, presentation worsens w growth

Question 3

What are some embryological defects?

Answer 3

Facial clefts- most common anomaly (1:680)- range of environment/genetic
First arch anomalies

Question 4

What are some facial cleft conditions?

Answer 4

Unilateral
Bilateral
Forme fruste- mild presentation
Mandibular
Mid face- holoprosencephaly (hemispheres fail to divide)- more severe- incompatible w life

Question 5

What are clinical issues relevant to facial anomalies?

Answer 5

Appearance 
Hearing/speech difficulties 
Dental anomalies eg. Crowding
High caries risk
Growth/scarring from surgery
Oronasal fistula
Skeletal III pattern
Psychology/well being

Question 6

How is hearing affected?

Answer 6

Abnormal palatal function affects inner ear drainage

Build up of fluid (glue ear)

Intermittent or long term hearing deficit

Question 7

How is speech affected?

Answer 7

Half of all children w cleft palate have speech difficulties

Backing- can be corrected w speech therapy
Nasality- palatal surgery

Question 8

Why might they have high caries risk?

Answer 8

Diet- soft happy foods
Less salivary flow
Tongue doesn’t cleanse teeth properly

Question 9

What are some first arch anomalies?

Answer 9

Hemifacial microsomia

Treacher Collins syndrome

Question 10

What is hemifacial microsomia?

Answer 10

1:4000 births
Spectrum
Embryo- 4/40 weeks- interrupted blood supple to brachial arch so restricted facial development
Maybe affect eyes/agenesis of ears

Question 11

How might an ear be attached?

Answer 11

Prosthetic removable and attachable via studs

Constructed from rib cartilage carved into C and Y shape and local tissue expansion

Question 12

What is Treacher Collins syndrome?

Answer 12

1:50000 births
Autosomal dominant/mutation of gene controlling TREACLE protein
Affects amount/flow of mesenchyme into first and second pharyngeal arches
Wide spectrum

Common features- hypoplastic maxilla esp. zygomatic arches and mandible, ear anomalies (atresia of auditory canals)- BAHA*, ocular anomalies (coloboma), cleft palate/high arched palate, airway problems

*bone anchored hearing aid

Question 13

What are some development defects

Answer 13

Craniosynostoses eg. Crouzons, Aperts, Achondroplasia
~premature fusion of one+ fibrous sutures resulting in distortion/abnormal development
1:2000- 20% linked to syndromes
Autosomal dominant/spontaneous mutation

Question 14

What is Crouzons syndrome?

Answer 14

1:25000
Spectrum
Premature fusion of sutures- abnormal skull development and raised intra cranial pressure

Clinical features- facial appearance, set back mid face, significant class III, prominent mandible, hydrocephalus, choanal atresia, high arched palate, speech/hearing difficulties

Question 15

What is Apert syndrome?

Answer 15

Similar facial presention
Slightly more significant narrowing of maxilla
Also associated syndactyly (fusion of fingers) and complex learning difficulties

Question 16

What is achondroplasia?

Answer 16

1:15000 to 1:40000

Cause shortened limbs (dwarfism)