Mutifaceted care of OSA: The role of mandibular advancement splints.

Mandibular advancement splints (MAS) are increasingly being used to treat obstructive sleep apnea (OSA). They work by protruding the patient's lower jaw in a forward position, thereby creating more space and reducing obstruction to breathing. MAS are now recommended to be used for the treatment of snoring with mild to moderate OSA, and for any sleep apnic unable to tolerate continuous positive airway pressure (CPAP) therapy.[1] Although CPAP therapy is consistently more effective, patients often tolerate MAS better.[23] The superior patient satisfaction associated with the use of MAS reflects the relative convenience of this form of treatment. Imaging studies have shown that MAS enlarge the upper airway dimensions by specifically increasing the lateral dimensions of the velopharynx.[45]

In this issue of “Lung India,” Upadhay and colleagues have illustrated how they were able to successfully treat a patient of sleep apnea with MAS and CPAP who was earlier unable to tolerate CPAP therapy and was considered not fit for surgery.[6] The patient had severe OSA with an apnea-hypopnea index (AHI) score of 66 and an Epworth sleepiness scale (ESS) score of 20, and not receiving any treatment would have left him highly susceptible to such consequences of sleep apnea as the increased risk of heart diseases and diabetes. The authors, however, did not elaborate why the patient could not be treated with MAS alone, which could have been gradually titrated, even though the approach has been documented to work.[7] This is otherwise a very common clinical scenario where a number of patients are unable to tolerate CPAP and thus the need for multifaceted sleep medicine services.

Adjustable MAS appliances allow progressive protrusion of the mandible, and the amount of anteroposterior mandibular movement varies considerably among patients. Multiple studies have shown that MAS efficacy is related to the amount of mandibular advancement,[8910] and determining the optimal degree of mandibular advancement is the most important step in using MAS therapy successfully.[1112] This is similar to CPAP in that the amount of pressure required for each patient cannot be predetermined based on OSA severity or craniofacial characteristics; therefore, to determine the amount of CPAP pressure required for each patient, there is a need of a titration night or the use of an auto-CPAP machine. In other words, the complexity required for effective CPAP is mainly related to the adjustability of the pressure, a unique pressure of 8 not being adequate for everyone, and the complexity required for effective MAS mainly depends on it being custom-made and allowing for titration/protrusion of the mandible.

There are several published randomized controlled trials (RCTs) comparing MAS to CPAP. Most of these RCTs have found that MAS and CPAP have a similar impact on daytime sleepiness and quality of life.[131415] Despite MAS being inferior to CPAP in ability to reduce the AHI score, it is hypothesized that a higher compliance to MAS likely translates to a similarly adjusted AHI score and effectiveness. Success with MAS treatment has been associated with factors such as female gender, younger age, supine-dependent OSA, lower body mass index (BMI), smaller neck circumference, and craniofacial factors; however, a reliable, validated method for prediction in the clinical setting has yet to be established.[116] MAS are well-tolerated; however, short-term side effects are common, although generally minor and transient. Long-term dental changes are for the most part subclinical but can be problematic for a minority of patients.[17] MAS are a form of dental-based treatment for a medical sleep disorder and, as such, an interdisciplinary care model is considered important for the attainment of optimal patient outcomes.

An important point to discuss is the cost-benefit analysis of a treatment. It is known that titratable appliances require consultation and adjustments provided by a dentist skilled in sleep medicine and that their fabrication is more expensive. Despite fixed MAS being typically less expensive and requiring a shorter period of adjustment, they are significantly less effective. A patient's economic status may be a factor in his/her choice of treatment. Patient-tailored treatment is synonymous with good medicine, and lifelong therapies are very dependent on the patient's cooperation and adherence. We believe that it is important to include patients in the decision-making process regarding their treatment and also to offer more than one type of therapy.