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Nasal Airway Obstruction and Precision Oral Appliance Therapy in the Treatment of OSA by Edward T. Sall, MD, DDS, MBA
W
hile there has been increased acceptance of Mandibular Advancement Splints (MAS) in the treatment of OSA, physicians have concerns about the overall efficacy of OA’s to the known high efficacy of CPAP. It is clear that OSA is a complex disease and that the “gold standard” notion of CPAP or the one treatment approach to OSA is not consistent with our current understanding of the pathophysiology of OSA. While there has been increased awareness of the nonanatomic factors (loop gain, arousal index, and pharyngeal collapsibility) in the pathogenesis of OSA, anatomic factors are still felt to be responsible for the majority of the etiology of OSA.
Figure 1: A recent poster presented at the 2022 World Sleep Congress
22 DSP | Summer 2022
Oral appliances have greatly evolved since the introduction of monobloc and non-custom appliances, and previous papers have shown increased efficacy of custom appliances versus monobloc. Many physicians are only familiar with legacy appliances and are unaware of fourth generation precision appliances. Precision Oral Appliance Therapy (OAT) is characterized by bite transfer with <1mm of variance and a titration mechanism that holds the jaw in the target position throughout treatment. A recent poster presented at the 2022 World Sleep Congress on 115 consecutive cases showed that a precision oral appliance is capable of successfully treating patients with all levels of severity with most patients treated to an AHI <5. 29 severe patients with an average AHI of 51.5 were treated to a final average of 9.5 (Figure 1). This suggests that precision oral appliance therapy should be considered as the primary form of therapy for all levels of severity of OSA depending on the preference of the patient. It is known that multilevel anatomic obstruction is often present in snoring and obstructive sleep apnea. Since the nose is the first anatomical boundary of the upper airway, nasal airway obstruction may contribute to sleep disordered breathing. The Starling resistor model, the unstable oral airway, the nasal ventilatory reflex and the role of nitric oxide (NO) may potentially explain the role of nasal pathology in OSA. While