Internal Mandible Distractors
Mandibular distraction (also known as distraction osteogenesis) involves precise cuts being made in the lower jaw bone. A device is applied to bridge the cut part of the jaw. The device is secured to the bone with small screws. On a daily basis, the device is designed to slowly separate the cut jaw anywhere from 0.3-1.0 mm a day. This allows for new bone to form in the cut area while lengthening the lower jaw. As the jaw moves forward, it pulls the tongue with it out of the windpipe. The devices that are applied to the cut area of the jaw may be either internal (where the device is buried beneath the skin) or external (where the device is outside the body and it is connected to the bone via pins). Each has their advantages and disadvantages. What is best for the infant will be reviewed by the surgeon.
Jaw Distraction Surgery
Pierre Robin sequence only requires treatment at a young age if the windpipe is obstructed, causing difficulty breathing. The cause of the breathing obstruction may be multifactorial. Mild cases of breathing obstruction from Pierre Robin may be treated with side or face-down positioning and close monitoring. This allows the tongue to fall forward and out of the windpipe. A nasopharyngeal airway, a small tube inserted in the nose, can also increase airflow. Surgical interventions are considered if the above conservative measures fail or if the Pierre Robin is severe. There are two surgical approaches to managing Pierre Robin: tongue-lip adhesion and mandibular distraction. A tongue-lip adhesion involves a surgical fusion of the tongue undersurface to the lower lip. This technique is designed to pull the tongue forward and out of the windpipe. A second procedure is required later to release the tongue from the lip when the infant has grown enough. Mandibular distraction (also known as distraction osteogenesis) involves precise cuts being made in the lower jaw bone. A device is applied to bridge the cut part of the jaw. On a daily basis, the device is designed to slowly separate the cut jaw. This allows for new bone to form in the cut area while lengthening the lower jaw. As the jaw moves forward, it pulls the tongue with it out of the windpipe.
Pierre Robin sequence (also known as Pierre Robin syndrome) is a condition where babies are born with
a small lower jaw and a tongue that falls into the back of the throat. These two factors may block the
windpipe and cause difficulty breathing. The obstruction in airflow through the windpipe can be so
severe that a breathing tube may need to be placed after birth. In these infants, a full airway evaluation
needs to be performed by an experienced clinical team. This may include a sleep study, where blood
oxygen levels are monitored as the infant sleeps. Children born with Pierre Robin often (but not always)
additionally have a cleft palate.
KLS Martin, a family-run medical technology company based in Germany, has developed numerous
distraction devices adapted for various regions of the craniofacial skeleton. The specific device selected
will depend on the area of the jawbone that needs to be lengthened. For infants with Pierre Robin
sequence, the Zurich micro II distractor is a common choice. It is an internal device with a small arm that
protrudes from the skin, usually just behind the ear. It has the ability to length the bone by 15-30mm.
The design of the device is symmetrical (allowing for use on the right and/or left side) and the system
has an anti-relapse ratchet that prevents accidental backward movement.