Craniofacial microsomia affects 1 in 5,600 newborns (or fewer), but there are any number of conditions that may affect the facial nerves required to create a smile. More often than not, a process known as “facial reanimation” can restore that ability.

Note: the same procedure is used to treat facial paralysis in stroke victims, in children and adults who suffer injuries to their facial nerves, and in survivors of cancer following resection of a tumor.

Craniofacial Microsomia

A child’s first smile brings the greatest imaginable joy.

Unfortunately, many children are born with congenital deficiencies that affect their ability to smile. This can ultimately affect the child’s range of expression and self-esteem. More often than not, this facial paralysis is the result of a condition known as craniofacial microsomia.

There is a spectrum here: while the condition is relatively common, not every affected child will experience facial paralysis. Additionally, paralysis may be limited to one side (unilateral) or it might be bilateral, affecting both sides of the face.

The challenge for your certified craniofacial team—and the goal of any craniofacial plastic surgeon—will be to restore a symmetrical smile, and there are two available methods for doing so. Both are effective so long as they are applied in the “right” patient:

  • Microsurgical Technique – Free Tissue Transfer
  • Rotational Muscle Flap – Temporalis Flap

Microsurgery and Facial Reanimation

The advent of microsurgery has been a blessing for parents and their children affected by Craniofacial Microsomia. (The technique is also effective in facial reanimation for adults following stroke, injury, or the removal of a tumor.)

Microsurgery to restore facial animation involves what is known as a “free tissue transfer.”

If “free tissue transfer” is the recommended approach, your surgeon will “borrow” muscle from one part of the body—typically the inner thigh (gracilis)—and use it create the functional unit that will restore the smile.

The challenge is to find a nerve that will activate that new muscle. In cases of unilateral paralysis, there may be a useable nerve on the side of the face that is functioning normally. Alternately, a nerve graft may be more appropriate (most often borrowing from the soral nerve of the lower leg). In either case, following transfer of the muscle and an adequate period of healing, this second surgery completes the procedure.

Thereafter, the patient will learn how to activate that muscle in order to smile, and for that we thank goodness for brain plasticity—the human brain’s amazing ability to adapt and change!

Traditional Technique for Facial Reanimation

“Free tissue transfer” is a complex, microsurgical technique and may not be appropriate for every patient. It is a relatively new technique, as opposed to the “Temporalis Flap,” an approach that has been used to correct facial paralysis for many years.

In the past, surgeons would correct paralysis of a child’s smile by rotating the temporalis muscle, which is one of the muscles that enables us to chew our food. With a portion of this muscle relocated to the corner of the mouth, the child is able to clench his or her teeth in order to make a smile.

Still very much in use today, the “Temporalis Flap” is a simple procedure that nevertheless invites complications, including morbidity at the donor site. Often, the temporalis muscle is not long enough and an alloplast—or synthetic implant (link to Medpore)—is required.

A more recent variation uses only the tendon of the temporalis muscle, minimizing donor site morbidity and reducing complications.


Surgery to affect facial reanimation is most often performed in children between the ages of 6 and 8 years-old. Sometimes parents may want to wait longer, and often parents will do so in order to allow the child to make his or her own decision.

We wait until the child is older because there needs to be enough tissue to work with. In other words, they need to grow a little bit so that there is ample musculature. After 6 or 8, however, a child that cannot smile may risk other social or psychological costs and so we do not recommend waiting too much longer unless the child is opposed to surgery.

Generally, however, the surgery can be done whenever the child is ready and the rare complications, usually minor twitching at the eyes whenever the patient smiles, can be treated with Botox.