Sidman

Tongue-lip adhesion (TLA) will certainly work in neonates with minimal airway compromise. There is however the “elephant in the room” with TLA, and that is the issue of swallowing after the surgery. Most studies looking at this carefully are showing very high rates of gastrostomy, even in nonsyndromic children. Our own papers show a very low rate of needing gastrostomy with distraction osteogenesis (DO) during infancy.

We also feel that nasal airway (“trumpet”) is underutilized in most institutions in the management of micrognathic children. If indeed the trumpet works, then TLA is not necessary as they both accomplish the same thing. Either the trumpet or TLA really only works in the less severely affected children.

The last item to address is the issue of isolated micrognathia. We have found very few children with micrognathia who have airway obstruction based on the micrognathia and do not also have full blown Pierre Robin sequence (RS) with cleft palate, glossoptosis, and micrognathia. When we are referred airway obstructed babies without the triad of Pierre Robin, then invariably the airway issue is caused by something other than micrognathia and DO is almost never the appropriate treatment.

In summary, we have little use for TLA as we would use either a nasal trumpet, or proceed to DO of the mandible. The significant deleterious effects of TLA on swallowing should not be discounted, and seems to be almost universal.

Tatum

MDO for airway compromise in the neonate/infant micrognathic patient was introduced in 1999. Until then positioning, special feeding techniques, temporary pharyngeal airways, TLA, and tracheotomy were the main options. Similar controversy existed then among those options. The addition of MDO has not diminished the controversy. There has been no definitive comparative study published that clearly shows the superiority of one method over the others. This conundrum exists due to several factors.

First of all, RS and other micrognathic patients are an inhomogeneous group. Syndromic RS patients tend to be more severely affected than nonsyndromic RS patients. Other diagnoses associated with micrognathia such as Nager, Treacher Collins, and craniofacial microsomia are frequently worse as well. Secondly, there is significant variation in patient population presenting to various institutions. This variation depends on numerous factors. Location of the center is one of the most important. The larger the referral base, the more likely the center is to have exposure to rare conditions. If that center has trained many providers who remain in the area, those providers can manage the more straightforward patients referring on only the most challenging cases. Large metropolitan areas might have several centers competing for patients. One of the more interesting factors is the specialty of the provider. It has been suggested that certain specialties tend to favor one management option over the others. The choice seems to come down to training, experience and comfort level with the various options. That being said, there is some useful information in the literature.

It is reasonable to say there is a consensus in the literature that RS patients should be managed with a spectrum of intervention that is appropriate to severity. Where the controversy begins is after positioning, special feeding techniques, supplemental feeding and temporary airway adjuvants fail. Abel and colleagues recently reported 86.5% of their Robin patients managed successfully with positioning or nasopharyngeal airways. Relatively long term home use of nasopharyngeal airways has been suggested. The surgical interventions of lip-tongue adhesion (LTA), MDO and tracheotomy all have their costs and benefits. The trend is to save tracheotomy for those who fail the first two because once trached these patients tend to not be decannulatable for several years. LTA has waned a little as well, but there are still strong advocates. Cost has recently been looked at as a factor, and tracheotomy loses there because of the long term care needs. The difficulty is knowing which patients will benefit most from each intervention. Recently the GILLS score (gastroesophageal reflux disease, intubation, late airway surgery, low birth weight) has been shown to have predictive value for LTA. Neurologic impairment has been added to this list as well. Additionally, other airway pathology worsens the prognosis.

To summarize, most PRS patients will be successfully managed with nonsupine positioning, special feeding techniques and temporary nasopharyngeal airway support allowing growth and maturation to reduce the problems. Patients with gastroesophageal reflux disease, requiring intubation in the first 24 hours, of low birth weight, or with neurologic or other airway impairment are more likely to need surgical intervention. My first choice is MDO except for the patients with severe neurologic impairment or other airway pathology. They are more likely to be managed with tracheotomy.

Sidman

DO for the mandible is almost never indicated in adults as sagittal split osteotomy is the procedure of choice. It is indicated in midface deficiency if there is a need to bring the maxilla forward more than 10 to 12 mm. Single stage movement of this amount will result in some relapse due to the pressure of the soft tissue envelope. In this case, maxillary DO would be indicated even in an adult. Most of the time, two jaw (mandible and maxilla) surgery is needed in these cases.

In summary, only the most severe midface deficiency patients need maxillary distraction, and virtually no adult patients need mandibular distraction.

Tatum

This is an interesting question. The adult orthognathic surgery population is also heterogeneous. There are those patients with lifelong malocclusion and skeletal disharmony who have decided to address the problem for whatever reason in adulthood rather than earlier. These patients typically do not have major skeletal discrepancies (greater than 6–8 mm) and do not require large movements. The main advantages of distraction over conventional orthognathic surgery are the gradual application of soft tissue stretch and the elimination of bone grafts for large moves. Distraction does not generally offer an advantage over traditional orthognathic surgery procedures such as the Le Fort I and the sagittal split ramus osteotomies for these patients. A couple of exceptions are when bone grafts are needed such as for maxillary down grafting or possibly in patients over 40 for whom the risk of bad splits and permanent inferior alveolar nerve injury increases with sagittal split osteotomies. Additionally, those with significant scarring such as cleft patients can benefit. Cleft patients also benefit from gradual movement being less likely to cause velopharyngeal insufficiency than all at once movements.

The occasional patient who makes it to adulthood with large skeletal discrepancies that would involve significant soft tissue stretch and bone grafts to correct would be a good candidate for distraction. The soft tissue stretch is gradual and bone grafts are not needed.

Another situation where distraction might be desirable in the adult patient is in the management of obstructive sleep apnea. These patients may or may not have malocclusion and/or skeletal discrepancy, but either way the goal is typically to expand the upper airway as much as possible. These patients often require movements or one or both jaws of greater than 10 mm. The catch is that the movements of both jaws must be perfectly coordinated to maintain presurgical occlusion or result in a desired occlusal change in coordination with orthodontic therapy. This task is arguably easier when the movements are made all at once and fixated in precise positions. However, finishing orthodontics is frequently necessary to fine tune the occlusion after conventional orthognathic surgery, and it can also assist in achieving good final occlusion after distraction. Finally, in some situations the techniques are being integrated to provide the best of both for the patient.

Sidman

We have little experience with this, but when we do need to, we use external devices with concomitant orthodontic devices for guidance of trajectory and occlusion.

Tatum

Both types of devices can achieve good results. Some surgeons have used them together. The exposure and osteotomies are similar. There are numerous differences, advantages and disadvantages. External devices pull the distracted segment forward from multiple attachment points. Internal devices push the segment forward from laterally. The external devices have the obvious burden of the visible bulk and constant presence around the head and face interfering with activity and potentially becoming dislodged. There is a risk of pin perforation of the skull and meningitis or brain damage. They cause additional scalp scarring often cause some facial scarring depending on distractor attachment points.

The main advantages of an external device are the multivector control over the distracting segment, multiple attachment points in the midface, and the easy removal of the device after the consolidation phase. The multivector control allows for “on the fly” adjustments of distracting segment movement and very precise fine tuning of the occlusion. The multiple attachment points combat the tendency of the central and lateral portions of the midface to distract at different rates due to different resistance to skeletal movement at those locations. Device removal is a brief incisionless procedure involving loosening this screws.

Internal devices avoid the bulky exposed device although the activators must remain exposed typically behind the ears. Once they are secured in place they are unlikely to migrate or become dislodged. The main disadvantages are no vector adjustability and a fairly major procedure to remove the devices. The procedure must be very carefully planned. Once the devices are placed, the final position of the distracted segment is set. The only choice is to continue activation or to stop. Some minor adjustments can be achieved with orthodontic appliances and elastics. Device removal involves completely repeating the initial exposure to place the devices. It can be even more difficult because the distraction places the distal end of the device further away from the initial incision.