Cleft palate can occur alone (isolated cleft palate) or in conjunction with cleft lip (cleft lip and palate). In both cases cleft palate results from total or incomplete merging of the left and right palatal shelves. The palate is the roof of the mouth and it separates the oral and nasal cavities.
There are two parts to the palate - the hard and soft palate. The hard palate which is made of bone makes up the front half of the palate and is situated within the arch of the gums and teeth. The soft palate is the floppy part of the palate that is attached to the back of the hard palate. The back end of the soft palate is marked with the uvula which hangs down from the soft palate. The soft palate is comprised of many small muscles that are important in speech. Some of the soft palate muscles contribute to swallowing, but an intact soft palate is not necessary for normal speech. Unfortunately, an intact soft palate is needed to be able to speak normally.
When there is a cleft of the palate there is a separation of the muscles that are important for speech. These muscles contract and cause the back of the soft palate to meet the back of the throat. This allows us to build up pressure in the mouth and throat and we let this air out in a controlled way to make normal speech sounds. A cleft of the palate makes it impossible to create a good seal to separate the mouth and nose. This results in air leaking out of the nose while speaking and abnormal speech.
Similarly there can be regurgitation or leaking of fluid out through the nose during feeding. Thankfully, children with cleft palate can usually feed normally with the appropriate bottle and guidance with feeding (see Cleft Feeding).
Another issue that children with cleft palate face is a predisposition to having middle ear infections. This infection risk comes from a tendency for these children to accumulate fluid in the middle ear. Normally the fluid from the middle ear drains through the eustachian tube into the throat. The same muscles that help close the palate with speech also pull on the eustachian tube causing it to open. When there is a cleft palate the muscle can't pull on the eustachian tube as well therefore it does not drain the ear as effectively. These children usually need tube placed in the ear drums to help drain the fluid and prevent infection. It is important to have close follow up with an ears nose and throat (ENT) doctor in a cleft team to follow hearing and avoid middle ear infection.
Cleft palate is normally repaired at 9-12 months of age. This is to allow the infant to grow without sacrificing quality in speech outcomes. Children who have the palate repaired after 12 months of age are predisposed to having more difficulty developing normal speech.
Occasionally a child will have difficulty with air leaking after palate repair and this can cause abnormal speech. This is called velopharyngeal insufficiency (VPI). Occasionally this will respond to speech therapy, but about 1 in 5 children with cleft palate will need a second surgery to normalize their speech.