The case report “Using Overnight Pulse Oximetry to Manage Oral Appliance Therapy” by Ronald S. Prehn, DDS, contains gross misrepresentations of the recommendations of the American Academy of Sleep Medicine (AASM). First, contrary to Prehn’s first citation, the AASM’s 2011 technology evaluation paper provides no support for prescribing overnight pulse oximetry testing to prescreen for obstructive sleep apnea (OSA).1 Single channel devices (eg, pulse oximetry alone) were excluded from the review, which “was specifically limited to classification and evaluation of the performance characteristics of the technology itself” and did not make clinical recommendations.

Second, the AASM clinical guideline for portable monitoring (PM) clearly states, “We restricted our review to Type 3 devices because these are used most frequently in the outpatient setting.”2 Therefore, any mention of PM in the guideline refers to a Type 3 device (usually using 4–7 channels) and not to a Type 4 device with 1 or 2 channels (eg, pulse oximetry alone). Furthermore, the PM guideline clearly states, “The Task Force recommends that PM testing be performed under the auspices of an AASM-accredited comprehensive sleep medicine program.” Therefore, contrary to Prehn’s assertion, the AASM guideline provides absolutely no substantiation for the use of pulse oximetry alone to evaluate the response to oral appliance therapy (OAT), and it does not support the use of overnight pulse oximetry by dental sleep practitioners. The 2015 clinical practice guideline for OAT that was developed jointly by the AASM and the American Academy of Dental Sleep Medicine (AADSM) provides the additional clarification that sleep physicians—not dentists—“should conduct follow-up sleep testing to improve or confirm treatment efficacy.”3


Nathaniel F. Watson, MD, MSc

Third, Prehn’s assertion that the AADSM treatment protocol recommends the use of pulse oximetry testing is misleading. The AADSM protocol states, “The dentist may obtain objective data during an initial trial period to verify that the oral appliance effectively improves upper airway patency during sleep.”4 However, “objective data” is ambiguous and is not defined in the protocol. Therefore, until additional clarification is provided by the AADSM, it is disingenuous to state bluntly that the AADSM recommends pulse oximetry.

Finally, the AASM has broad concerns about Prehn’s care model. A dentist who uses a diagnostic test to evaluate the efficacy of a treatment for a medical disorder such as OSA is potentially making a diagnostic decision that is beyond the scope of practice of dentistry, which could expose the dentist to medical liability and malpractice. Furthermore, medical reimbursement of a diagnostic test by a dentist is a questionable—and potentially fraudulent—billing practice.

Nathaniel F. Watson, MD, MSc, is the 2015-2016 president of the American Academy of Sleep Medicine (AASM) and is board-certified in sleep medicine and neurology. He is a professor of neurology at the University of Washington in Seattle, co-director of the University of Washington Medicine Sleep Center and director of the Harborview Medical Center Sleep Clinic.


1. Collop N, Tracy S, Kapur V, et al. Obstructive Sleep Apnea Devices for Out-Of-Center (OOC) Testing: Technology Evaluation. J Clin Sleep Med. 2011 Oct 15;7(5):531-548.

2. Clinical Guidelines for the Use of Unattended Portable Monitors in the Diagnosis of Obstructive Sleep Apnea in Adult Patients. Collop NA, Anderson WM, Boehlecke B, et al. Portable Monitoring Task Force of the American Academy of Sleep Medicine. J Clin Sleep Med. 2007 Dec 15;3(7):737-47.

3. Ramar K, Dort LC, Katz SG, Lettieri CJ, Harrod CG, Thomas SM, Chervin RD. Clinical practice guideline for the treatment of obstructive sleep apnea and snoring with oral appliance therapy: an update for 2015. Journal of Dental Sleep Medicine 2015;2(3):71– 125.

4. American Academy of Dental Sleep Medicine. AADSM Treatment Protocol: Oral Appliance Therapy for Sleep Disordered Breathing: An Update for 2013. June 2013. Available at

Rebuttal to Letter from Nathaniel F. Watson, MD, MSc, Concerning the Use of Pulse Oximetry for Titration of Mandibular Advancement Appliances for the Treatment of Sleep-disordered Breathing

I appreciate the well thought out, relevant concerns Dr Watson has raised in his response to this article. Working closely with sleep physicians for most of my professional career, I understand his concerns. I want to say from the onset that I have always followed published protocol for treating SDB and OSA and have always desired the highest level of care for our patients. Coming from a multigenerational family of dentists and physicians, I have always been a champion of collaboration between our professions. In that light, I am concerned about the spirit of this response. I am not sure if his response represents the position of the whole AASM, or if this is just his personal feelings.

First, in regards to his objection to using the Collop 2011 paper as a citation, he is correct in his assertions. That was my mistake and I am glad he pointed that out. I have made the appropriate change in the final draft of the printed article. (Editor’s Note: This change, as well as several clarifications, have also been made to the online version of the article. The original article remains toward the bottom of the page for transparency. The reference to the printed article is to the article on pages 12-16 of Sleep Review‘s November 2015 issue.) The reference I intended to cite was Collop 20071 “Clinical Guidelines for the Use of unattended Portable Monitors in the Diagnosis of Obstructive Sleep Apnea in Adult Patients” This was published by the Adult Obstructive Sleep Apnea Task Force of the AASM.

Second, there are two basic principles any medical doctor uses to determine efficacy of any medical treatment. One is subjective symptoms (the patient complaint). Two is objective signs (what testing for the disorder, or the exam indicates). So in order for the dentist to determine if treatment of the airway with the oral appliance (OA) is effective, both must be considered. There is no other objective testing for sleep-disordered breathing (SDB) or obstructive sleep apnea (OSA) available to the dentist other than blood desaturation levels as revealed by pulse oximetry, especially since Type 3 testing, according to protocol, is to be interpreted by a boarded sleep physician.

Dr Watson seems to indicate a desire that the dentist does no objective study to determine efficacy. So the dentist would have to rely on subjective symptoms alone. But a study by Fleury2 in 2004 documents the fact that subjective symptoms alone are not able to determine if the oral appliance is effective. So if what Dr Watson desires becomes reality, then the dentist will not know if the oral appliance is effective until he sends the patient back to the MD for objective testing. If the final HST or PSG from the MD shows that the OA is not effective, then what? The patient has to return to the DDS for more advancement only to return again. That is a waste of resources for one, and a total disrespect to the patient and the treating dentist. But if the DDS were to determine the objective effectiveness of the OA before the patient is referred back to the MD, then the evaluation of the MD as to the dissipation of the OSA is much more effective. The dentist does his job, so the physician can do his.

The need for objective monitoring is clear in the research other Fleury 2004. Collup 2007 on page 740, it states:

“1.4. PM may be indicated to monitor the response to non-CPAP
treatments for obstructive sleep apnea, including oral appliances,
upper airway surgery, and weight loss.”

To the same point that objective monitoring of OA are protocol, on page 272 of Epstein 20093 (This also was published by the “Adult Obstructive Sleep Apnea Task Force of the AASM.”) states

“For patients with OSA, the desired outcome of treatment includes the resolution of the clinical signs and symptoms of OSA and the normalization of the apnea-hypopnea index and oxyhemoglobin saturation (Standard)… OAs should be monitored shortly after initiation of treatment and then as frequently as needed in order to assure patient accommodation, comfort, adequate device titration, and adherence, and to assess symptoms and side effects (Consensus).”

While it is obvious that Type 4 monitors cannot determine AHI, it can determine “oxyhemoglobin saturation” (an objective sign of airway patency). So with pulse oximetry with symptoms, the effectiveness of the OA in securing the patency of the airway can be determined.

I made it abundantly clear in this article that only the sleep physician can determine resolution of OSA and the sleep MD can determine the AHI in compliance to all these guidelines. I never once made any assertion that the dentist is making any determination as to the disposition of the medical disorder called OSA, either in screening or in final testing. The only purpose of Type 4 monitoring suggested in this article is to monitor the effect of advancing the mandible has on the oxyhemoglobin saturation of the patient (which reflects the patency of the airway). That information, in conjunction with the signs and symptoms, will allow the sleep dentist to determine if the patient is ready to return to the sleep MD for final evaluation of disposition of the sleep apnea. I made is quite clear in my protocol in this article, that the sleep MD makes the diagnosis and the sleep MD makes the determination of the final disposition or resolution of the OSA, which is in line with the protocols of the AASM and the AADSM.

Third, the sleep DDS is responsible for oral appliance therapy, and that includes all the side effects of that therapy as well as the effectiveness of the device. Besides signs and symptoms, the only way to determine if the MAS is effective is to objectively measure (as recommended by the AADSM) the oxyhemoglobin saturation. This is only to measure the effectiveness of the device, NOT the disposition of the breathing disorder. It is my belief that the dentist must be taught the correct way to use pulse oximetry to make that determination.

Dentists are medical doctors of the of the masculatory system which includes the airway, tongue, and associated structures. When any disorders of the human body are associated with those structures, it is the dentist that is called to diagnose (cause of obstruction, not OSA) and treat. SDB is such a disorder. OSA is a complex disorder that especially concerns the cardiovascular system. That disorder falls into the calling of medical doctors. Physicians are to diagnose and manage OSA. When patients with diagnosed OSA or other forms of SDB, then the dentist is called to manage the airway.

Dentists do not attempt to put any restrictions for any treatment that any physicians desire to provide. That would be contra to the mutual respect our professions have always had. It would violate the basic tenants of both of our professions. So I don’t understand why Dr Watson, as a representative of the physicians as president of the organization that represents boarded sleep physicians, communicate in this response the desire to limit the ability of the dentist to practice our profession. As a third generation dentist with three generations of physicians in our family, this is incomprehensible to me. For a sleep MD to suggest that the sleep dentist should not be “allowed” to use this tool is disingenuous and will further alienate our professions. I have worked all my life to promote collaboration. This response by Dr Watson represents an effort to restrict our ability to provide quality medical treatment, and has the possible effect of exposing the sleep dentist to medical liability and malpractice as well.

Fourth, I don’t understand the spirit or the motivation of his assertion that “medical reimbursement of a diagnostic test by a dentist is questionable—and potentially fraudulent—billing practice.” What is the foundation of this accusation? Billing is not even addressed in this article! I don’t charge a fee for this service as it is part of the therapy and not billed separately. In the medical world every procedure is unbundled to maximize insurance reimbursement. That is the only sense I make of this assertion. But what Dr Watson may not realize, in the world of dentistry, we do not unbundle, rather include any service necessary in the treatment in one fee. And again, pulse oximetry to titrate the MAS is not for diagnosis, so no fee is charged by the dentist.


Ronald S. Prehn, ThM, DDS

I think Dr Watson has some valid points that need to be resolved between our professions. Unfortunately, The use of HST has become a flash point of contention between our professions. As a dentist who has spent all of his life working to collaborate with my colleagues in the medical profession, the spirit of his letter is very sad and I hope does not represent the feelings of all the members of the AASM, of who I have the utmost respect. Many are my friends. I believe the protocol presented in this article represents a way of using pulse oximetry that respects both the physician’s duty to diagnosis and manage OSA, and the dentist’s duty to deliver effective oral appliance therapy. It is my hope that our professions can come together in mutual respect and determine a protocol for the treatment of OSA. When I teach, the foundation of my message is always collaboration of our professions. I hope for the sake of all of our patients and our professions, that this message reaches home to everyone concerned.

Ronald S. Prehn, ThM, DDS, is the owner of Restore TMJ & Sleep Therapy, a patient-centered dental practice that focuses on the diagnosis and treatment of headaches/facial pain, temporomandibular disorders, and sleep-breathing disorders in The Woodlands, Tex. He is a member of the American Academy of Orofacial Pain, the American Academy of Sleep Medicine, the American Academy of Dental Sleep Medicine, and the Appliance Therapy Practitioners Association. He is a board certified diplomate of the American Board of Orofacial Pain and the American Board of Dental Sleep Medicine, of which he sits on the board of directors.

1. Collop, et al, Clinical Guidelines for the Use of unattended Portable Monitors in the Diagnosis of Obstructive Sleep Apnea in Adult Patients. J Clin Sleep Med. 2007; 3(7):737-747

2. Fleury, et al, Mandibular Advancement Titration for Obstructive Sleep Apnea. Chest 2001; 125:1761-1767.

3. Epstein, et al, Clinical Guideline for the Evaluation, Management and long-term care of Obstructive Sleep Apnea in Adults. J Clin Sleep Med. 2009; 5(3):263-276