The word "cleft" refers to an opening or space. We know that
all clefts are different. They can occur at one or more
different places on the face, such as the lips, the palate, or
the gum ridge (alveolus). In human development, the right and
left sides of the face fuse near the midline. A cleft results
when this fusion does not properly occur. Clefts can be of
different sizes; some are more severe than others.
Cleft of the Lip
A cleft lip appears as a gap in the upper lip. This opening
can occur on the left or right side, or on both sides. A cleft
that occurs only on one side is called a unilateral cleft. In a
bilateral cleft, openings are present on both sides of a
central upper lip segment, called the prolabium.
Not all lip clefts appear the same. There may be a barely
noticeable notching of the red part of the lip, a ridge down
extending down the lip from the nasal base, a partial division
of the lip, or a complete division of the lip up into the floor
of the nose.
You will hear us discuss the appearance of the nose because
the anatomic changes that occur in cleft lip also affect the
appearance of the nose. The growth, development, and correction
of the nose in children with cleft lip is a specific area of
interest to the Duke team’s surgeons.
Clefts of the Palate
The palate separates the nasal cavity from the oral cavity:
"The floor of the nose is the roof of the mouth." A cleft
palate is an opening in the palate that allows communication
between the oral and nasal cavity. The palate is important for
swallowing and the development of speech.
Like the cleft of the lip, cleft palate results from an
alteration in the sequence of events that lead to fusion of
right and left sides in the midline. The extent of the cleft
will again vary from person to person. The palate, or roof of
the mouth, is composed of two sections. The front half, just
behind the teeth, is a bony section called the hard palate.
Behind this is the soft palate containing muscles used in
swallowing, eating, and speech. A cleft can occur in the soft
palate only or extend forward through part or all of the hard
palate.
Both the hard and soft palate are covered by a mucous
membrane. In certain cases, the mucous membrane may appear
intact, but the bones and/or muscles beneath it may not be
appropriately fused in the midline. Despite its almost normal
surface appearance, the underlying changes still can create
functional problems, particularly for speech. This type of
cleft is known as a submucous cleft palate.
Cleft of the Alveolar Ridge
The alveolar ridge, in front of the hard palate, is the bony
ridge just above the gums. Your baby's upper teeth will erupt
through this bony ridge. As with the lip and palate, clefts
here can also occur on the right, the left, or both sides. If
the cleft affects the alveolar ridge, whether completely or as
a minor notch, it can affect the teeth. Sometimes extra teeth
are seen; sometimes teeth will be missing. Often, the alignment
of the teeth is affected. This is the very important reason
that your cleft team includes dental specialists. They can
provide needed treatment or work with your own local dentists
and orthodontists to find the best treatment plan for your
child.

Cleft of the soft palate only.

Cleft of the soft and hard palate.

Complete unilateral cleft of the lip, alveolus, and palate.

Complete bilateral cleft of the lip, alveolus, and
palate.
Duke Guide to Care of Children with Cleft Conditions