Syndromes Of The Head And Neck; Craniofacial Genetics

Front 1

- Premature closing of the cranial sutures leads to:
- Brachycephaly (short head)
- Trigonocephaly (triangle-shaped head)
- These Pt's are NOT mentally deficient

Back 1

Crouzon's Disease (Craniofacial Dysostosis)
- 1 out of 25,000 to 65,000 births
- Autosomal dominant, some spontaneous
- Ocular proptosis (protruding eyeballs due to shallow orbits)
- Hypertelorism (widely spaced eyes)
- Hypoplastic maxilla with short upper lip
- Mal occlusion (crowding, 2/3 have cross bite)
- Possible "cloverleaf" skull (broad looking forehead, most severe cases)
- Anterior open bite
- 50% or more have poor vision and hearing deficits
Treatment: multiple surgeries

Front 2

- Acrobrachycephaly (tower skull)

Back 2

Apert Syndrome
- One out of 65,000-160,00 births
- Autosomal dominant
- Possible "cloverleaf" skull in severe cases
- Ocular proptosis
- Hypertelorism
- Down slanting of lateral palpebral fissures

Front 3

Back 3

Apert Syndrome
- Syndactyly of hands and feet
- Possible mental retardation
- Hypoplastic maxilla
- Mandibular prognathism (maxillary crowding with class III map occlusion)
- Possible cleft soft palate
- Gingival thickening w/ possible delayed eruption
- Shovel Shaped incisors in 1/3 of pts.

Front 4

Back 4

Apert Syndrome

Front 5

- Autosomal Dominant w/ irregular pattern (1/2 of cases spontaneous)
- Affects structures developing from the 1st and 2nd branchial arch

Back 5

Treacher Collins Syndrome (Mandibulofacial Dystosis)
- One out of 10,000 to 50,000 births
- Mandibular micrognathia due to condylar and coronoid hyperplasias
- "Bird-like" appearance
- Zygomatic atrophy (depressed cheeks)
- Coloboma (notch lower eyelid) (75%)
- Downward slanting of lower eyelid
- External and internal ear defects (possible hearing loss, including deafness) (Microtia)
- Preauricular hair growth
- Malocclusion
- Cleft palate in 1/3 of cases
Treatment: possible cosmetic surgery.

Front 6

Back 6

Osteogenesis Imperfecta (Lobstein's Disease)
- Opalescent dentin in a pt. w/ osteogenesis imperfecta.
- Inherited disorder of collagen maturation that results in bone w/ thin cortex, fine trabeculation and diffuse osteoporosis
- Bone fracture easily, w/ inability of the matrix to fully mineralize which leeds to exaggerated caller formation.
- 1 in 8,000 births.

Front 7

Back 7

Osteogenesis Imperfecta (Lobstein's Disease)
- Bite-wing radiograph of the same pt. showing shell teeth w/ thin dentin and enamel of normal thickness
- Bone deformities and fragility (pts confined to wheelchair)
- Dentinogenesis imperfecta-like teeth in 25% of cases
- Possible malocclusion due to maxillary hypoplasia

Front 8

- Possible Blue sclera

Back 8

Osteogenesis Imperfecta (Lobstein's Disease)
- Four major types (mild to severe forms; I, II, III, & IV)
- Lethal types occur in 10% of cases
- Sever non-lethal types occur in 20% of cases
- Mild form may not be apparent at birth and fractures decline at puberty
- Possible hearing loss.
- No specific treatment.

Front 9

Back 9

Cleidocranial Dysplasia
- Autosomal dominant and spontaneous
- Clavicles are absent or hypoplastic
- Skull deformities, brachycephaly, hypertelorism, frontal and occipital bossing that produces enlarged and abnormally shaped head.
- Short stature, cardiac anomalies.

Front 10

Back 10

Cleidocranial Dysplasia
- Lacks secondary cementum
- Increased cleft palate and high palate
- Over-retained primary teeth, delayed eruption of permanent teeth, supernumerary teeth (some distorted crowns)
No known treatment

Front 11

- Sporadic or may occur w/ other syndromes
- 5 to 22 per 100,000 births ( or 1 per 4,545 to 20,000 births)
- Cleft Palate (leads to feeding and speech problems)
- Mandibular micrognathia
- Glossoptosis (airway obstruction due to posterior displacement of tongue) (lack of tongue musculature)
- Respiratory and feeding problems common

Back 11

Pierre Robin Syndrome

Front 12

- Autosomal dominant disease
- 23,000 americans affected w/ This syndrome
- Abnormally soluble collagen (problem w/ connective tissue protein)

Back 12

Marfan Syndrome (Arachnodactyly)
- Tall, slender stature, large hands and fingers, chest deformities
- Long narrow skull and bones, cardiovascular defects (mitral valve prolapse, aortic regurgitation, aneurysms, etc.)

Front 13

Back 13

Marfan Syndrome (Arachnodactyly)
- High arched palate, bifid uvula, malocclusion
- Possible early death (has occured in undiagnosed athletes)
- Need annual medical exam and possible limit physical activity.