10 - Cleft lip and palate

Cleft lip (cheiloschisis) and cleft palate (palatoschisis), which can also occur together as cleft lip and palate are variations of a type of clefting congenital deformity caused by abnormal facial development during gestation. This type of deformity is sometimes referred to as a cleft. A cleft is a sub-division in the body's natural structure, regularly formed before birth. A cleft lip or palate can be successfully treated with surgery soon after birth. Cleft lips or palates occur in somewhere between one in 600-800 births.

Causes of cleft

During the first six to eight weeks of pregnancy, the shape of the embryo's head is formed. Five primitive tissue lobes grow:

a) one from the top of the head down towards the future upper lip; (Frontonasal Prominence)
b-c) two from the cheeks, which meet the first lobe to form the upper lip; (Maxillar Prominence)
d-e) and just below, two additional lobes grow from each side, which form the chin and lower lip; (Mandibular Prominence)
If these tissues fail to meet, a gap appears where the tissues should have joined (fused). This may happen in any single joining site, or simultaneously in several or all of them. The resulting birth defect reflects the locations and severity of individual fusion failures (e.g., from a small lip or palate fissure up to a completely malformed face).

The upper lip is formed earlier than the palate, from the first three lobes named a to c above. Formation of the palate is the last step in joining the five embryonic facial lobes, and involves the back portions of the lobes b and c. These back portions are called palatal shelves, which grow towards each other until they fuse in the middle.[5] This process is very vulnerable to multiple toxic substances, environmental pollutants, and nutritional imbalance. The biologic mechanisms of mutual recognition of the two cabinets, and the way they are glued together, are quite complex and obscure despite intensive scientific research.[6]

Cleft lip
If the cleft does not affect the palate structure of the mouth it is referred to as cleft lip. Cleft lip is formed in the top of the lip as either a small gap or an indentation in the lip (partial or incomplete cleft) or continues into the nose (complete cleft). Lip cleft can occur as one sided (unilateral) or two sided (bilateral). It is due to the failure of fusion of the maxillary and medial nasal processes (formation of the primary palate).


Unilateral incomplete cleft lip (left side)


Cleft lip, unilateral complete


Bilateral complete




Infant with a unilateral cleft lip and palate

Cleft palate
left palate is a condition in which the two plates of the skull that form the hard palate (roof of the mouth) are not completely joined. The soft palate is in these cases cleft as well. In most cases, cleft lip is also present. Cleft palate occurs in about one in 700 live births worldwide.[1]

Palate cleft can occur as complete (soft and hard palate, possibly including a gap in the jaw) or incomplete (a 'hole' in the roof of the mouth, usually as a cleft soft palate). When cleft palate occurs, the uvula is usually split. It occurs due to the failure of fusion of the lateral palatine processes, the nasal septum, and/or the median palatine processes (formation of the secondary palate).

The hole in the roof of the mouth caused by a cleft connects the mouth directly to the nasal cavity.

Note: the next images show the roof of the mouth. The top shows the nose, the lips are colored pink. For clarity the images depict a toothless infant.


Incomplete cleft palate


Unilateral complete lip and palate





Bilateral complete lip and palate

A direct result of an open connection between the oral cavity and nasal cavity is velopharyngeal insufficiency (VPI). Because of the gap, air leaks into the nasal cavity resulting in a hypernasal voice resonance and nasal emissions.[2] Secondary effects of VPI include speech articulation errors (e.g., distortions, substitutions, and omissions) and compensatory misarticulations (e.g., glottal stops and posterior nasal fricatives).[3]. Possible treatment options include speech therapy, prosthetics, augmentation of the posterior pharyngeal wall, lengthening of the palate, and surgical procedures.[2]

Submucous cleft palate (SMCP) can also occur, which is an occult cleft of the soft palate with a classic clinical triad of bifid uvula, notching of the hard palate, and zona pellucida.

causes of cleft lip and palate
The cause of cleft lip and cleft palate formation can be genetic in nature. A specific variation in a gene that can have abnormalities causing the Van der Woude Syndrome increases threefold the occurrence of these deformities has been identified by Zucchero et al in 2004[7] as reported by the BBC.[8]

Environmental influences may also cause, or interact with genetics to produce, orofacial clefting. Some environmental factors that have been studied include: seasonal causes (such as pesticide exposure); maternal diet and vitamin intake; retinoids- which are members of the vitamin A family; anticonvulsant drugs; alcohol; cigarette use; nitrate compounds; organic solvents; parental exposure to lead; and illegal drugs (cocaine, crack cocaine, heroin, etc).

If a person is born with a cleft, the chances of that person having a child with a cleft, given no other obvious factor, rises to 1 in 14. Research continues to investigate the extent to which Folic acid can reduce the incidence of clefting.

In some cases, cleft palate is caused by syndromes which also cause other problems. Stickler's Syndrome can cause cleft lip and palate, joint pain, and myopia. Loeys-Dietz syndrome can cause cleft palate or bifid uvula, hypertelorism, and aortic aneurysm. Cleft lip/palate may be present in many different chromosome disorders including Patau Syndrome (trisomy 13). Many clefts run in families, even though there does not seem to be any identifiable syndrome present.

Treatment

Cleft lip and palate is very treatable; however, the kind of treatment depends on the type and severity of the cleft.

Most children with a form of clefting are monitored by a cleft palate team or craniofacial team through young adulthood. Care can be lifelong. Treatment procedures can vary between craniofacial teams. For example, some teams wait on jaw correction until the child is aged 10 to 12 (argument: growth is less influential as deciduous teeth are replaced by permanent teeth, thus saving the child from repeated corrective surgeries), while other teams correct the jaw earlier (argument: less speech therapy is needed than at a later age when speech therapy becomes harder). Within teams, treatment can differ between individual cases depending on the type and severity of the cleft.

Pioneering Surgeon Dr. Victor Collins has devised the first non skin graft procedure for the treatment of infantile unilateral incomplete and complete cleft lips. This technique involves the partial circumcision of the foreskin and then being applied to the affected area. This technique has led the way in the the modern day removal of the two most common types of cleft lip.

[edit] Cleft lip treatment

Within the first 2-3 months after birth, surgery is performed to close the cleft lip. While surgery to repair a cleft lip can be performed soon after birth, the often preferred age is at approximately 10 weeks of age, following the "rule of 10s" coined by surgeons Wilhelmmesen and Musgrave in 1969 (the child is at least 10 weeks of age; weighs at least 10 pounds, and has at least 10g haemoglobin). If the cleft is bilateral and extensive, two surgeries may be required to close the cleft, one side first, and the second side a few weeks later. The most common procedure to repair a cleft lip is the Millard procedure pioneered by Ralph Millard. Dr. Ralph Millard performed the first procedure at a Mobile Army Surgical Hospital unit in Korea.[9]

Often an incomplete cleft lip requires the same surgery as complete cleft. This is done for two reasons. Firstly the group of muscles required to purse the lips run through the upper lip. In order to restore the complete group a full incision must be made. Secondly, to create a less obvious scar the surgeon tries to line up the scar with the natural lines in the upper lip (such as the edges of the philtrum) and tuck away stitches as far up the nose as possible. Incomplete cleft gives the surgeon more tissue to work with, creating a more supple and natural-looking upper lip.

Cleft palate treatment
Often a cleft palate is temporarily closed using a palatal obturator. The obturator is a prosthetic device made to fit the roof of the mouth covering the gap.

Cleft palate can also be corrected by surgery, usually performed between 6 and 12 months. Approximately 20-25% only require one palatal surgery to achieve a competent velopharyngeal valve capable of producing normal, non-hypernasal speech. However, combinations of surgical methods and repeated surgeries are often necessary as the child grows. One of the new innovations of cleft lip and cleft palate repair is the Latham appliance. The Latham is surgically inserted by use of pins during the child's 4th or 5th month. After it is in place, the doctor, or parents, turn a screw daily to bring the cleft together to assist with future lip and/or palate repair.

If the cleft extends into the maxillary alveolar ridge, the gap is usually corrected by filling the gap with bone tissue. The bone tissue can be acquired from the patients own chin, rib or hip.

Speech and hearing treatments

A tympanostomy tube is often inserted into the eardrum to aerate the middle ear. This is often beneficial for the hearing ability of the child. Speech problems are usually treated by a speech-language pathologist. In some cases pharyngeal flap surgery is performed to regulate the airflow during speech and reduce nasal sounds.

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