Where does cleft occur?
- In embryonic development at points of fusion
- Can include lip (possibly with alveolar ridge) and/or palate (roof of mouth)
- Difference in: size, shape, location, orientation, vary in length and width
What is a cleft lip?
The result of a failure of parts of the lip to come together during embryologic development
What is cleft palate?
Occurs when the roof of the mouth does not fuse normally leaving large opening between oral/nasal cavities (varies in length/width)
Types of cleft lip
- normal
- complete: goes up through the nostril
- incomplete: does not reach the nostril
- bilateral: cleft on both sides
types of cleft palate
- normal
- soft cleft palate
- hard cleft palate
- complete palate cleft
- bilateral palate cleft
Embryological closure of the closure of the lip and alveolar ridge begins around how many weeks of gestation?
7
The closure of the hard palate and velum start around how many weeks of gestation?
9
The fusion begins at the incisive foramen and moves....
outward
what causes cleft lip/palate?
- chromosomal: abnormality in number or structure (Down syndrome, monosomy, trisomy)
- gene defect: caused by abnormality in genes (mutant genes, rare syndromes, prader-willi)
- teratogenic: environmental (alcohol, valium, x-ray, excessive vitamin a)
- multifactorial
- unknown/other: maternal-intrauterine conditions, diabetic mom, amniotic bands, folic acid
why might an SLP recommend altering liquid viscosity in a child with cleft palate?
slow the speed of bolus transit to facilitate airway protection
How to get a prenatal diagnosis
- 50-60% indentified in utero via imaging
- ultrasonography
- amniocentesis
- chronic villus sampling
developmental problems associated
- feeding difficulties
- hearing difficulties & middle ear disease
- speech sound difficulties
- phonation disorders
- language difficulties
- reading difficulties
- psychosocial issues
Treatment
- Team approach: care coordinator, plastic surgeon, dentist, SLP, ENT, social worker, psychologist, educational specialist, dietician
SLP's role
- feeding, reading, language, speech
- advocate for client for optimizing communication
- complete pre-post surgical evals
- determine status of voice, speech, language, and resonance
- provide input for secondary procedures: vpi procedures
what is an oronasal fistula?
opening between oral and nasal cavities
challenges of cleft palate with feeding
- problems vary with type and size of anomaly
- creation of pressure differential
- recurrent otitis media
- prolonged feeding session (stress, fatigue, bonding issues, inadequate weight gain/slow growth, failure to thrive)
- milk spillage and nasal cavity
- intraoral muscle coordination and mechanical movements (coordination of suck, swallow, breath pattern)
What is velopharyngeal insufficiency?
is usually caused by an abnormality of the soft palate. It is common in children with cleft palate or a sub mucous (under the skin) cleft. Repair of cleft may or may not alleviate the problem.
What is velopharyngeal incompetence?
caused by poor movement of the velopharyngeal structures. This is often due to a disorder or injury of the brain or cranial nerves. Cerebral palsy and traumatic brain injury are examples of disorders that cause velopharyngeal incompetence.
VP function assessment
- perceptual
- indirect: (nasometry, acoustic measures), infer function (oral airflow, air pressure, and resonance balance), therapy v no therapy
- direct: observe anatomy and function at rest, lateral still x ray, videofloroscopy, endoscopy, surgery vs no surgery
What cells help with the development of the face and palate?
neural crest cells
Why are neural crest cells important to the formation of various facial structures?
These cells contribute to the development of the bones, muscles, and connective tissues of the face, as well as the oral and nasal cavities. Any disruption or delay in the migration of these cells can lead to abnormalities in facial and palatal development, including cleft lip and cleft palate.
When does the closure of the lip and alveolar ridge occur?
7th week of gestation
How does the fusion of the lip and alveolar ridge occur?
Fusion starts at the midline, near the incisive foramen, which is a small opening behind the front teeth. From there, the fusion progresses outward on both sides, eventually closing the gap in the upper lip and forming the upper jaw's gum tissue.
When does the closure of the hard palate and velum occur?
9th week of gestation
How does the fusion of the hard palate and velum occur?
Fusion starts at the incisive foramen, similar to the lip closure, and extends backward towards the back of the throat. The completion of palatal fusion results in the separation of the oral and nasal cavities.
What is the first step in the process of lip formation?
the fusion of the alveolar ridge
Describe the formation of the alveolar ridge
It begins at the incisive foramen and progresses anteriorly, resulting in the fusion of the premaxilla with the maxillary bones at the bilateral incisive suture lines. This fusion forms the alveolar ridge and contributes to the formation of the upper jaw and gum tissue.
What happens after the alveolar ridge is formed?
Following the fusion of the alveolar ridge, closure continues to form the base of the external nose and then proceeds downward to form the upper lip. The prolabium (central part of the upper lip) and the two lateral lip segments fuse, giving rise to the philtrum (the vertical groove in the center of the upper lip) and philtral ridges. The final part of lip formation is the fusion of the vermilion, which is the colored portion of the upper lip.
What happens to the tongue during palatal fusion?
Regarding palatal fusion, prior to its occurrence, the tongue is positioned superiorly and posteriorly in the nasopharynx. The palatal bones are initially vertical and located on each side of the tongue. Around 7 to 8 weeks of gestation, the mandible starts to drop down and move forward, leading to the descent and anterior movement of the tongue. This allows the palatal bones to transition from a vertical to a horizontal position.
How does the formation of the hard palate occur?
Once the tongue is out of the way, the fusion of the palatal bones with the premaxilla begins at the area of the incisive foramen. The fusion proceeds in a posterior direction along the median palatine suture line, completing the formation of the hard palate. The vomer bone, which contributes to the nasal septum, descends and fuses with the superior surface of the hard palate, effectively separating the nasal cavity into two halves.
What happens after the formation of the hard palate?
After the formation of the hard palate, the velum (soft part of the palate at the back of the mouth) fuses in the midline, forming the median raphe. Finally, the uvula, a fleshy projection hanging from the back of the soft palate, is formed. The fusion of the hard palate and velum is typically completed by around 12 weeks of gestation.
The development of a cleft involves a combination of
endogenous (internal) factors, such as inherited genetic or chromosomal abnormalities, and exogenous (external) factors, which are environmental influences during pregnancy.
The exact etiology of a cleft in an individual is often
multifactorial, meaning that it involves the interaction of multiple genetic and environmental factors.
Do genes alone cause cleft palate?
Several genes have been identified that, when defective, can contribute to a genetic predisposition for clefts. However, the presence of these defective genes alone may not be sufficient to cause a cleft. Specific environmental factors during pregnancy, such as maternal nutrition, exposure to certain medications, tobacco smoke, alcohol, or infections, can play a role in triggering the expression of these genes, leading to the development of a cleft.
When a couple has a child with a cleft, their risk of having another child with a cleft is
increased compared to the general population
The recurrence risk for CL/P in such cases is estimated to be around
3% to 5%
What are teratogens?
substances that can cause congenital malformations, as well as physical interference with fetal development
What teratogens are associated with cleft lip and palate?
cigarette smoke, alcohol consumption, certain medications like Dilantin, valium, anticonvulsants, and corticosteroids, lead pollution, viral infections (such as rubella and influenza), maternal nutritional deficiencies (including lack of vitamin B-6), and maternal obesity
What are examples of physical interference as an exogenous factor?
fetal positioning or crowding, placental abnormalities, and micrognathia (small mandible) can disrupt the normal fusion of the palate. For instance, in Pierre Robin sequence, where the mandible is abnormally small and fails to move down and forward at the appropriate time, the elevated position of the tongue in the nasopharynx can interfere with palatal fusion, resulting in a wide cleft palate.
How do amniotic bands affect embryonic development?
These bands occur when the amnion, the membrane surrounding the embryo and fetus, ruptures and forms strands of tissue. These strands can attach to various body parts, acting as tourniquets and impeding blood supply to developing structures. Amniotic bands can lead to amputations of limbs or digits, as well as clefts of the lip or palate and other oral and facial deformities.
What is a complete cleft?
A complete cleft refers to a cleft that extends along the embryological fusion line(s) all the way to the incisive foramen.
What is an incomplete cleft?
an incomplete cleft does not extend all the way to the incisive foramen
What does the primary palate refer to?
The primary palate refers to the structures anterior to the incisive foramen, which includes the alveolar ridge and the lip.
What does the secondary palate refer to?
The secondary palate includes the structures posterior to the incisive foramen, such as the hard palate (excluding the alveolar ridge), the velum (soft part of the palate), and the uvula.