Chapter 31 Sleep and Snoring
“Esthetic” dentistry implies a move to a more pleasing countenance by enhancing the smile and inspiring confidence with an assured appearance. Sleep-disordered breathing, ranging from snoring to medically significant sleep apnea, demonstrates a very clear, direct, and dramatic connection to tooth grinding and clenching. Bruxism is very frequently present in the snoring and obstructive sleep apnea (OSA) patient. The most powerful reflex action possessed by the mammal is to protect the airway. There is clear evidence that the act of clenching of the teeth will result in some increase in the size of the airway. For many generations of dentists the root causes of bruxism have been issues of debate. Dentistry has considered stress and habit to be among the causes of this phenomenon. A shutdown of the airway may be the beginning of a long trail of clenching and grinding in the sleep apnea patient. Bruxing patients will tear apart the beautiful dentistry achieved through the many esthetic procedures available to dentists in the twenty-first century. It is common within a practice to be able to recount experiences in which cases with great similarities in dental requirements have resulted in a wide variation of time of service of the restorations. Often the patient who tears apart the dental work is a sleep-disordered–breathing patient whose condition went undiagnosed. The dentist, being unaware of the threat to the dental health, will have gone ahead in good faith to restore and protect the dentition, only to find that the restoration may break down as a result of an undiagnosed and untreated OSA condition.
No group of health professionals is more ideally placed to screen for people with sleep-disordered breathing than the dental team. Patients see their dentists on a regular and ongoing basis. Only on rare occasions is the dental service accompanied by pain, suffering, and general health disease. Compared with a medical practice, in which patient appointments are most commonly associated with some form of medical concern, dental appointments are much more benign. Dental patients who come in for regular recall visits can and should be screened for other issues related to their dental concerns. A mother sitting in the waiting room while her child is having a recall appointment is the ideal target for information on the snoring of her husband. There is nothing esthetic about the appearance of a snoring patient with the usual dropped jaw accompanied by ugly noises.
The snoring population has been the subject of much derision for generations. Often the target of cartoonists and humorists, the snorer has long been the butt of jokes. The development of sophisticated technology to define the medical importance of oxygen deficiency during sleep was the starting point for redefining of the relationship between snoring and sleep apnea. The term sleep apnea was not used in general medical practice as late as the 1970s. With the availability of the defining technology, medical researchers moved to seek treatment for nocturnally oxygen-deprived patients. Although there are distinct differences among some classifications of sleep apnea, the focus of this chapter is OSA.
In response to the need for therapy for this condition, a home ventilator device was developed. The device delivers continuous positive airway pressure (CPAP). The CPAP machine is a lifesaving device for people with the more severe form of sleep apnea. The downfall of CPAP therapy is that it is generally overprescribed, in the sense that general medical practice has been to prescribe CPAP whenever any form of sleep apnea is present. The management of the device is difficult. There are difficulties with finding a mask that fits. The device requires that during sleep the wearer must be attached to a “blower” by a hose, which limits the ability to turn over. In general, a CPAP device is invasive to the sleep posture and comfort. If one’s life is in danger every time the eyes are closed, which is unquestionably the case for the severely apneic patient, the patient will usually accommodate to anything. It is the milder levels of sleep apnea that, although medically significant, do not necessarily catch the attention of the patient. In the mild sleep apnea patient, the use of the CPAP machine is limited by the inconvenience and discomfort for the patient as well as the noise and disruption to the sleep of the sleep partner.
The use of oral appliances to treat sleep-disordered breathing became common after the late 1980s. The first recorded use of manipulation of the tongue position to alleviate OSA occurred in 1934. The technique lay dormant for the next 50 years until patient compliance with the use of CPAP therapy was identified as being problematic and other solutions were required. Since 1990 an enormous amount of research has been done, which eventually led to the release of the American Academy of Sleep Medicine position paper on the use of oral appliances in the treatment of sleep apnea and snoring. Until the release of this paper, which was 10 years in the making, one significant barrier to the use of oral appliances was the position taken by the insurance community identifying the therapy as being “experimental” and therefore not a covered service. Since the release of this position paper the landscape has dramatically changed, with most insurers, including some governmental agencies, now covering the service.
In considering oral sleep appliances, it is necessary to relate function and esthetics. Appliances used to treat sleep disorders offer protection for the teeth against damage resulting from destructive oral habits and jaw muscle responses related to sleep apnea.
Protection is important whether one has a natural dentition or a restored dentition. One important distinction is that the dentist treating the sleep disorder and the restorative dentist are not necessarily the same person. Appliance selection and the transmission of knowledge about the sleep disorder treatment to the general or specialist dentist are of paramount importance. There may be repercussions from wearing a jaw advancement device during the night. The five most feared words in the vocabulary of the sleep dentist is “Doctor, my bite has changed.” Although a change in bite may be inevitable in some patients, ensuring that the patient is aware of and understands this possibility is only one part of the equation. Ensuring that other members of the patient’s dental team are aware is critical to avoiding unnecessary inconvenience and perhaps medico-legal complications.
Research at the University of Montreal has shown that for patients who have OSA, the use of a single-arch maxillary night guard can make that patient’s condition worse by a factor of 50% in half of the cases. This puts an entirely new light on the mass use of night guards to protect teeth from nighttime threats. If a patient exhibits the need for night guard therapy, the dentist should investigate the possibility of an OSA problem. It is important to remember that snoring and OSA are a part of a continuum. Snoring is the first and most obvious sign of a compromised airway. From there patients proceed along the spectrum of sleep-disordered breathing. The airway that is obstructed but not occluded presents a condition known as upper airway resistance syndrome. These patients are struggling to breath. The body response is hypertension leading to elevated blood pressure. In the dental realm is the natural body response of bruxism to alleviate a compromised airway.
One very common aspect of sleep-disordered breathing is that the signs and symptoms of the condition do not necessarily fall in line with the empirical numbers established by sleep studies. Many patients with a mild diagnosis will exhibit aggressive symptoms, and the converse is also true. Some of the more severely affected patients disavow the daytime sleepiness symptoms associated with OSA, whereas many diagnosed with mild OSA have significant and life-altering or life-threatening symptoms. OSA is divided into mild, moderate, and severe categories. Oral appliance therapy, as outlined by the American Academy of Sleep Medicine, is best suited but not necessarily limited to the treatment of OSA in the mild and moderate categories.
If the answer to any of these questions is “yes,” a more comprehensive screening is suggested. There are a number of validated questionnaires available. If the results indicate a high probability for OSA, the patient should be referred for a medical assessment and diagnosis. By virtue of training, experience, and licensure, dentists are not legally able to differentially diagnose patients who snore and do or do not have OSA. The opportunity to treat snoring patients exists. Proceeding with treatment without confirmation of the patient’s medical assessment engenders risk. The medical condition of OSA may be negatively affected by the use of oral appliances in some cases. Medical backup is not only advisable but essential.
A number of approaches are available for treating people with sleep-disordered breathing. The number one cause of this disorder is a genetic predisposition to the condition. Patients inherit a set of craniofacial characteristics that predispose to having a nighttime breathing problem. Typical Class II malocclusion patients are prime candidates because the tongue is jammed back owing to the mandibular positioning. Patients with a small air passage or a soft palate and uvula positioned low behind the tongue are at greater risk. The second of the “evil trio” is ageing. As one ages, every set of tissues in the body loses tone. This means that the collapsible tube called the velopharynx, which is inches long and is positioned right behind the tongue, will grow lax. The tube becomes progressively more collapsible over time. The third of the prime causes is being overweight.
When considering treatment alternatives, lifestyle changes are a first line of treatment. Treatment of a patient who is 40 pounds overweight will be a much greater challenge than if a loss of 20 pounds could be achieved. Lifestyle changes are the most cost-effective but may also be the most challenging.
Surgical approaches are a possibility. In appropriate anatomical situations, surgery may offer the only other “cure” for the problem. The surgical approach ranges from the most extreme—tracheostomy—to laser-assisted uvulopalatoplasty. Alteration of the throat anatomy/>