Distraction Osteogenesis

What is Distraction Osteogenesis?

Distraction Osteogenesis is a procedure that allows maxillofacial surgeons to correct skeletal deformities. Using different devices, they slowly pull apart bones to grow new bony segments between them. One benefit of distraction osteogenesis is that the volume of soft tissue overlying the bones is gradually increased as well. 

This treatment method was made popular by a Russian orthopedic surgeon named Dr. Gavriil Ilizarov. He has been credited with developing the modern technique. In the early 1990s, Dr. Joseph McCarthy pioneered the use of this treatment in the facial bones. 

Conditions Treated by Distraction Osteogenesis

Distraction osteogenesis can be used to treat a variety of congenital and acquired anomalies of the facial skeleton and jaws and reduces the need for bone grafts.

Some of the conditions treated are:

• Micrognathia: A condition in which the lower jaw is underdeveloped, resulting in an undersized chin. This can cause difficulty eating and speaking and upper airway obstruction.
• Craniosynostosis (Crouzon syndrome): A condition in which the bones of the skull close too early. This can cause the head to have an abnormal shape.
• Hemifacial microsomia: A condition in which one side of the face is underdeveloped. This can cause facial asymmetry and difficulty eating and speaking.
• Maxillary hypoplasia: A condition in which the upper jaw is underdeveloped. If left untreated, this can lead to dental problems and difficulty eating.
• Cleft palate: A condition in which there is an opening in the roof of the mouth. This can cause difficulty eating, speaking, and breathing.
• Pierre Robin Sequence: A condition characterized by a small lower jaw and cleft palate.
• Traumatic facial injuries: Severe and disfiguring facial injuries may require bony reconstruction to re-establish proper facial contours and restore function.

Distraction Osteogenesis Devices

There are three types of devices used in distraction osteogenesis. The device used will depend on the specific condition being treated. 

Devices that may be used include:

1. Rigid external distractors: These external devices are attached to the outside of the skull and face.
2. Internal distractors: These internal devices are placed inside the mouth and are gently elongated to increase the length of the jawbone.
3. Hybrid distractors: These devices are a combination of external and internal distractors and are used to treat conditions that involve both the face and jaw.

How Does it Work?

Intraoral (Inside the Mouth)

A small incision is made in the gum tissue, the bone is cut, and the distractor device is placed inside the mouth. The device is then attached to the bone with screws or wires. This is known as the latency period. During the 2nd phase, otherwise known as the activation period, the distractor device is lengthened by turning a dial or screw. This will slowly pull the bones apart.  The activation period generally takes several weeks. 

The third phase is the consolidation period and can last for several weeks. During this time the distractor device remains in place without changes in length to prevent relapse of the new bone formation. Once the desired results are achieved, the device is removed and the incisions are closed.

Risks and Potential Complications

There are a few risks and complications that can occur with distraction osteogenesis. 

These include:

• Infection. This is the most common complication. It is important to keep the surgical site clean and to follow your doctor’s instructions for care.
• Nerve damage. This can occur if the nerves are not properly protected during the osteotomy. Nerve damage can cause numbness, tingling, or pain in the affected area.
• Dislodgement of the distractor device. This may require a second procedure to properly secure it again.
• Bone loss. This can occur if the bones are not properly aligned during the consolidation period. Bone loss can cause the bones to become weak and susceptible to fracture.

Distraction Osteogenesis vs. Traditional Surgery

There are a few benefits of distraction osteogenesis over traditional surgery. 

These include:

• Less pain and swelling 
• Greater stability where significant movement of bony segments is involved
• Growth of soft tissue as well as bone during the activation period 

Frequently Asked Questions