Within the first 10 weeks of pregnancy, the two sides of the fetus’ mouth join together to create the lips and the palate.  Sometimes, however, something doesn’t “click” and this process never completes itself. When this happens, the child is born with a gap in the affected area; this gap is called a “cleft.”

Sometimes the palate fuses appropriately but the upper lip does not; this results in a cleft lip. Types of cleft lip include:

  • Unilateral: only affects one side of the lip.
  • Bilateral: affects both sides of the lip.
  • Complete: the cleft stretches into the base of the nose. Can be unilateral or bilateral.
  • Incomplete: the cleft is limited to the lip.  Can be unilateral or bilateral.

Sometimes, the palate does not fuse together in those first 10 weeks of pregnancy but the lip does, which results in an isolated cleft palate. The types of cleft palate include:

  • Cleft of the Primary Palate: the cleft affects the front portion of the palate (hard palate) near the teeth.
  • Cleft of the Secondary Palate: the cleft affects the rear portion of the palate (soft palate) towards the throat.
  • Complete Cleft Palate: the cleft affects both the primary and secondary palate.
  • Submucous Cleft Palate: a cleft of the soft palate exists but a layer of tissue covers it; thus it is not as readily seen.

It is possible for both the palate and the lip to be affected by clefting. This can occur in various combinations as described above.

Clefts of the lip are generally surgically repaired around 10 to 12 weeks of age. Clefts of the palate are generally surgically repaired around 10 to 15 months of age. The timelines of these surgeries may differ based on individual needs.

According to the Cleft Palate Foundation, one baby out of every 600 born in the United States is affected by a cleft.

It is important to note that the treatment of the cleft is rarely completed once the initial surgeries are performed. Often there are issues with speech and dental development that will require treatment at different times in the patient’s life. Examples of such treatments are adding bone to the mouth to support adult teeth and realignment of the jaw to create an even bite. These procedures, when needed, occur later in the child’s development and not in the early stages of treatment. It is very important to come to all appointments so the team can keep each patient on track.

Some diagrams to show the different types of clefts can be found here.