Kids Health Info

Jaw distraction mandibular distraction osteogenesis

  • Pronunciation of mandibular distraction osteogenesis: man - dib - u - lar dis- track - shon  osti - oh -jen - esis

    Jaw distraction is a surgical method of lengthening a small or recessed jaw if it causes severe or ongoing difficulty with breathing. It involves surgical implantation of distraction devices to the jaw, which allows the jaw bone to be lengthened. In most cases as the jaw is lengthened the airway opens up and enables the child to breathe clearly.

    Although this procedure is reserved only for cases of severe, life-threatening breathing problems, it has been very successful in alleviating airway obstruction and has prevented the need for tracheostomy (pron. track-ee-os-tomi) in most cases.


    Signs and symptoms

    Some children are born with a very small or recessed lower jaw. In most cases this does not cause any problems at all, but in a small percentage of infants it can cause significant problems in the first few months of life. This is mostly due to the tongue moving back into the throat when breathing in, partially or completely blocking the airway. This is known as upper airway obstruction, and can cause significant disruption to breathing and feeding. 

    Glossoptosis

    If upper airway obstruction is suspected, a period of time in hospital for investigations is usually required to evaluate breathing. Conservative non-surgical methods of improving the airway obstruction, such as positioning or insertion of a nasopharyngeal (pron. Nay - so - fa - ran - jeel) tube, will be attempted during this time.

    In a very small proportion of cases, non-surgical methods are not successful and breathing problems become life threatening, or are required for extended periods. If this is the case, jaw distraction may be considered an appropriate treatment.

    Investigations

    If severe or persistent upper airway obstruction occurs, one or more of the following investigations will be undertaken to decide if mandibular distraction is appropriate:

    • Overnight oximetry: in order to establish if the oxygen levels drop, by how much, and how often.
    • A sleep study: measures the multiple aspects of breathing to evaluate its effectiveness. This is one of the most reliable tools to measure the severity of airway obstruction.
    • Endoscopy: is a small tube that has a camera with a light at the end. It is sometimes required to look into the airway to determine the level of the narrowing or blockage in the airway.
    • A CT (computed tomography) scan will help the surgeons see the size and shape of the jaw before surgery. This allows surgeons to determine if mandibular distraction will be possible, and, if so, helps to plan the surgery.

    Treatment

    The decision to undertake jaw distraction is made in conjunction with a multidisciplinary team of medical and surgical staff. Each member has an interest in various aspects of airway obstruction. After considering the results of the tests, the team will decide if jaw distraction is appropriate. Jaw distraction will not be considered in an infant to correct facial dimensions alone, but is reserved for improving airway obstruction only.

    Procedure

    The surgery takes approximately two to three hours, and will require a period of time in hospital until the airway has opened up to allow clear spontaneous breathing.

    An incision is made through the skin under the jaw line, and then the jaw bone is carefully sectioned to enable a distraction device to be attached to either side of this separation in the bone. This happens on each side of the jaw.

    The distraction device is not visible after the operation except for two small rods that will protrude out from the chin or from behind the jaw line. These are called the distractor arms, and this method of distraction is called 'Internal mandibular distraction' (Figure 2).

    Jaw distractor pre expansion

    Figure 2.

    The day after surgery, each distractor arm will be turned a full 360°. This separates the pieces of bone by 0.5mm. This procedure is repeated every eight hours for approximately 10 days. During the eight hours between the turns, bone will grow to fill the space.

    This makes the jaw bone longer, and therefore moves the tongue away from the back of the airway, which makes the airway larger and makes breathing easier (Figure 3).

    Jaw distractor post expansion

    Figure 3.

    A period of time is then needed to allow the new bone to gain more strength, whilst the distraction device is in place to give it support. This occurs over approximately six to eight weeks following surgery. During this time your child can be at home, and can breathe and feed normally.

    Once the bone is strong enough, the distraction device can be removed. This involves another surgery, which will involve one or two nights in hospital.

    Risks

    The risks of mandibular distraction are minimal, and have been proven to far outweigh any risks of a tracheostomy or untreated airway obstruction.

    With all surgery there are potential risks, but in our experience, these have been rare or extremely mild, and may include infection, sensory disturbance in the face, damage to molars or faint scarring.

    At home care

    Once jaw distraction is complete there should not be any significant disruption to daily life. You can still feed your child normally, and extra diligence in keeping the area around the distractor arms clean will help prevent infection. The distractors are made of flexible titanium and should not be a problem if knocked or grasped by the infant.

    Follow-up

    Appointments will be made with the various doctors and surgeons involved in the distraction process during the hospital stay.

    Any problems with the distraction device, or signs of infection, such as redness pain or swelling, should be reported to the hospital's Maxillofacial Surgery department.

    Key points to remember

    • Non surgical methods to overcome airway obstruction are always applied whenever possible to avoid surgery on a small infant.
    • Jaw distraction is proven to be a much safer alternative to tracheostomy in an infant with severe upper airway obstruction. However it will not be undertaken to correct facial proportions alone.
    • A multidisciplinary team will decide if jaw distraction is an appropriate treatment option in each case.

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    Developed by The Royal Children's Hospital Neonatal Unit, in consultation with Plastics and Maxillofacial Surgery, Respiratory Medicine and Neonatology. Illustrations: The Royal Children's Hospital Educational Resource Centre. First published: January 2012
Disclaimer
This is intended to support, not replace, discussion with your doctor or healthcare professionals. The authors of these consumer health information handouts have made a considerable effort to ensure the information is accurate, up to date and easily understood. The Royal Children's Hospital accepts no responsibility for any inaccuracies, information perceived as misleading, or the success of any treatment regimen detailed in the handouts.