7. Congential Disorders Flashcards
Define a syndrome
group of medical signs and symptoms that are correlated to each other
Etiology of most syndromes is
genetics
How are syndromes names (now v.s past)
Past
-Named by the scientist that discovered it
Now
-Named by etiology
Most syndromes are autosomal (dominant/recessive)
dominant
T/F genetic mutations can have different phenotypic expressions
t
What is the second most common congenital physical birth defects
cleft lip and palate
Describe the differences in race with cleft lip and palate incidence
Asians> Whites> Blacks
2:1000)>(1:1000)>(0.5:1000
Describe the difference in cleft lip/palate between genders
CL +/- P –> M>F
CP alone –> F>M
Which is more commonly associated with syndromes when alone (cleft lip/cleft palate)
cleft palate
Likelihood that a mother with cleft lip/palate has a child with it
15%
likelihood that if 1 child has a cleft lip/palate so will the 2nd
4%
likelihood that if 2 children have a cleft lip/palate so will the next
9%
T/F Majority of cases of CL/CP are familial
F sporadic
T/F Environmental conditions (i.e smoking) have been linked to CL/CP
T- Mother smoking when pregnant, anticonvulsants, alcohol, etc.
When does lip and palate development occur
4-8 weeks in utero
The frontonasal prominance gives rise to
medial and lateral nasal prominances
Maxillary and mandibular prominances are derived from
neural crest cells from the first pharyngeal arch
Primary and Secondary palate formaiton
Primary Palate Formation
- Premaxilla
- Medial palatal shelves fuse
Secondary palate
- Posterior to incisive foramen
- Develops from 6-12 weeks
- Fusion of lateral palatal shelves
How does a cleft lip form
failure of fusion between the medial nasal process and maxilary prominance
How does a cleft alveolus form
failure of fusion between the medial and lateral palatine processes
How does a cleft palate form
Failure of fusion between the lateral palatal shelves
Veau classification of cleft lip
I= Noticing at vermillion boarder not extending into the lip II= Extends through the lip but not through the floor of the nose III= Extends into the floor of the nose IV= Bilateral
Veau Classification of the Cleft Palate
I= Soft palate only II= Soft and hard palate but not alveolous III= S+H palate and alveolus IV= Bilateral alveolar process involvement
Treatment phases for cleft lip and palate
0-6 mo
- Primary lip repair
- Presurgical orthodontitis??
12-18 mo.
-Primary palatal repair
12mo-6 yrs
- Prophylaxis and routine exams
- Speech surgery ??
- Secondary lip/palatal survery revision??
6-12 y/o
- Palatal expansion and alveolar grafe surgery?
- Phase I ortho?
- Protraction headgear?
12-18 y/o
- Phase II ortho
- Orthognathic surgery
18+ y.o
- Definitive prosthetic work??
- Definitive speech surgery??
- Definitive lip/nose/scar revision??
What is craniosynostosis
Premature closing of one or more cranial suture
Results from craniosynostosis
- Abnormal skull/forehead shape
- Asymmetrical eyes/ears
- Increased intracranial pressure
Syndromes associated with craniosynostosis
-Crouzon’s and alpert’s syndrome
What syndromes are assocaited with cleft palate
- Pierre Robine Sequence
- Digorge/ Velo-Cardio-Facial/ 22 deletion syndrome
- Mandibulofacial dysostosis
- Alpert’s syndrome
Tx for craniosynostosis
surgery in infancy to separate suture and reshape the bones
Describe the types of carniosynostosis
- Plagiocephaly
- Trigonocephaly
- Bracbhcephaly
- Scaphocephaly
- Plagiocephaly- coronal or lambdoid suture
- Trigonocephaly- metopic suture
- Brachycephaly- both sides of coronal suture
- Scaphocephaly- Sagittal suture
What is deformational plagiocephaly
Asymmetric head shape due to external forces (cranial sutures are normal)
Causes of deformational plagiocephaly
- Premature birth
- Muscular torticollis
- Restricted interuterine environment
- Sleeping in same position for extended periods of time
Tx of deformational plagiocephaly
Helmet molding
Gene and inheritance pattern of crouzon’s syndrome
- Autosomal dominant
- FGFR2/3 (role in bone growth)
Characteristics of Crouzon’s syndrome
Craniosynostosis
- Many sutures involved
- Brachycephaly, scaphocephaly, trigonocephaly
- Cloverleaf skull (severe) kleeblattschadel
- Increased intracranial pressure
- Shallow orbits
- Ocular proptosis (buldging eyes)
Mental deficiency in Crouzon’s is (common/rare)
rare
Dental finds of crouzon’s are
- Class III malocclusion
- Narrow palate
- Maxillary hypoplasia
Tc for Crouzon’s syndrome
many surgeries
Genes and inheritance pattern of Alpert’s disease
- Same as Crouzon’s
- AD
- FGFR2
Characteristics of Alpert’s syndrome
- Acrobrachycephaly (tower skull- coronal suture is fused)
- Syndactyly of digits 2,3,and 4
- Mental retardation common
- Downward slanting palpebral fissures
- Proptosis
- Hypertelorism
- Ear anomalies
Oral/Dental anomalies associated with alpert’s syndrome
- Cleft palate
- Class III malocclusion
- V-shaped arch
- Anterior open bite
Tx for Alpert’s syndrome
-Many surgeries
Another name for mandibulofacial dysostosis is
treacher collin’s syndrome
Gene and inheritance pattern of treacher collin’s
Chromosome 5q31 (TCOF1 gene) -AD
Syndromes associated with defects in structures derived from the 1st and 2nd pharyngeal arches are
- Mandibulofacial dysotosis
- Craniofacial (hemifacial) microsomia
Features of treacher collin’s syndrome
Hypoplastic Zygoma
- Narrow face
- Depressed cheeks
- Downslanting palebral fissues
- Coloboma= notch on outer portion of lower eyelid
- Ear anomalies
- Hearing loss
Oral findings with treacher collins
- Cleft palate
- Hypoplastic mandible (poor airway- difficulting feeding and breathing)
Tx for treacher collins
many surgeries
What is the most common facial birth defect after CLP
craniofacial (hemifacial) microsomia
Features of craniofacial microsomia
-Asymmetric presentation
-OMNES
O= Orbit
M=mandible
N=Nerves
E=Ear
S=Soft tissue
Inheritance pattern and genetics associated with the etiology of hemifacial microsomia
- usually spontaneous mutation- theorized to cause vascular deficiency in the formation of the fetal face (~4 week gestation
- Affects the structures derived from the 1st and 2nd pharyngeal arches
Triad of symptoms in Pierre Robin Sequence
-Micrognathia, cleft palate, and glossoptosis
What is glossoptosis
Posterior and low displaced position of the tongue causing airway obstruction
Why is Pier Robin Sequence not termed a syndrom
no genetic link
Cause of Pierre Robin sequence
Unknown- 3 theories
- Intrauterine mandibular constrint –> failure of tongue to descend –> failure of palatal shelves to fuse
- Absent or delayed lowering of tongue
- Neurogenic hypotonia –> lack of mandibular exercise
Characteristics of Pierre Robine Sequence
- Respiratory difficulties
- Some have congenital heart disease
Treatment for Pierre Robin Sequence
Possible mandibular distraction or mandibular advancement
Describe the gene and inheritance pattern of cleidocranial dysplasia
- CBFA1 (RUN X2) Chromosome 6 –> guides osteoblastic differentiation
- AD
Characteristics of cleidocranial dysplasia
- Clavicular (small or absent) and dental abnormalities
- Large head
- Frontal/ parietal bossing
- Small face (hypoplastic zygoma)
- Hypertelorism
- Broad nose
- Short
- Delayed closure of cranial sutures
Dental anomalies associated with CCD
- Unerupted multiple supernumerary teeth
- Distorted crown and root shape
- Lack cementure
How can you expose the unerupted teeth in CCD
ortho extrusion
Another name for progressive hemifacial atrophy is
parry romberg
Cause of Parry Romberg
unknown (theorized autoimmune diseases
Characteristics of progressive hemifacial atrophy
- Slow progressive atrophy of muscles and soft tissue of half the face
- Onset ~5-15 y/o
- Progresses for 2-10 years then stabilizes
Other health issues associated with Pery Romberg are
- Seizures
- Skin
- Pigmentation (Vitiligo)
- Eye problems
- Trigeminal neuralgia
Treamtne for progressive hemifacial atrophy
No known Tx
- Reconstructive surgery when stabilizes
- Experimental drugs targeting immune system
Another name for DiGeorge Syndrome
Velo-Cardio-Facial/ 22q11.2 deletion syndrome
Genetics and inheritance patterns of Digeorge syndrome
- Chromosome 22 (long arm)
- Autosomal dominant
Characteristics of Velo-Cardio-Facial syndrome
- Cleft palate
- Long face
- Underdeveloped lower jaw
- Hearing loss
- Heart anomolies
- Learning disabilities
- Thymic hypoplasia
Syndromes associated with ear anomalies are
- Alperts
- TC syndrome
Syndromes with Hypoplastic zygoma
- TC syndrome
- Cleidocranial Dysplasia (CCD)
Syndromes associated with hearing loss
- TC syndrome
- Hemifacial microsomia
- Digeorge/ Velo-cardio-facial syndrome
What syndrome is most commonly associated with cleft palate
Digeorge/ Velo-cardio-facial/ 22q11.2 deletion syndrome
