Changes in Upper Airway Anatomy, Quality of Life Measures, and Polysomnographic Parameters Using A Functional Dental Appliance

Although rising levels of obesity heavily influences the increasing rates of obstructive sleep apnea (OSA), detailed analysis of more basic etiology suggests a possible craniofacial origin. Specifically, modern humans' facial structures a slowly shrinking, which can narrow the upper airway. This is evidenced by the fact that rates of malocclusion and impacted (or non-existent) wisdom teeth are increasing in modern, Westernized countries.

Obstructive sleep apnea is a commonly seen condition characterized by multiple episodes of obstructed breathing during sleep, with intermittent hypoxia. Untreated OSA is associated with significantly higher rates of high blood pressure, diabetes, heart disease, heart attack, stroke, sudden death, and car accidents. The gold standard treatment for OSA is continuous positive airway pressure (CPAP), but compliance is poor. Initially, out of 100 patients, 20 will refuse CPAP. After one year 50% of the 80 remaining patients will be using CPAP, but only 50% will be using it effectively, leaving only 20 patients who are using CPAP effectively. (personal communication, Stepnowski).

An alternative option in people with mild to moderate OSA is a mandibular advancement device, which functions by pulling the genioglossus muscle forward. Long-term use of CPAP and mandibular advancement devices have been shown to aggravate malocclusion. Numerous surgical options are available for select patients, but only as a last resort.

In children, one uncommonly used, but effective form of treating OSA is by application of a palatal expander by an orthodontist. In theory, this option is effective due to the fact the palatal suture line is not completely fused in children. The general consensus in dentistry is that adults have fused midline palatal suture line and the hard palate cannot be expanded.

Recent work by numerous investigators suggests that palatal expansion can occur to significant degrees, even in adults. Case reports have been published with the AHI diminishing significantly after therapy. Not only can the hard palate widen, there can also be significant growth of new maxillary bone growth and anterior mandibular bone growth. Jaw development is linked to airway development.