You are in: eMedicine Specialties > Otolaryngology and Facial Plastic Surgery > PALATAL AND MAXILLOFACIAL SURGERY Snoring and Obstructive Sleep Apnea, Prosthetic ManagementArticle Last Updated: Jun 28, 2007AUTHOR AND EDITOR INFORMATIONSection 1 of 11
  Author: Arjun S Joshi, MD, Staff Physician, Division of Otolaryngology/Head and Neck Surgery, George Washington University Medical Center Arjun S Joshi is a member of the following medical societies: Alpha Omega Alpha, American Academy of Otolaryngology-Head and Neck Surgery, and American Medical Association Coauthor(s): Steven A Bielamowicz, MD, Professor of Surgery, Chief, Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, George Washington University; Alan A Z Alexander, MS, George Washington University School of Medicine; John M Truelson, MD, FACS, Chairman, Division of Head and Neck Surgery, Associate Professor, Department of Otorhinolaryngology, University of Texas Southwestern Medical Center at Dallas; D Heath Roberts, DDS, Director, Department of Oral Appliance Therapeutics, Sleep Medicine Associates of Texas Editors: Hassan H Ramadan, MD, MSc, Professor and Vice-Chair, Department of Otolaryngology-Head and Neck Surgery, Professor, Department of Pediatrics, West Virginia University; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Robert M Kellman, MD, Professor and Chair, Department of Otolaryngology and Communication Sciences, State University of New York Upstate Medical University; Christopher L Slack, MD, Otolaryngology-Facial Plastic Surgery, Private Practice, Associated Coastal ENT; Medical Director, Treasure Coast Sleep Disorders; Arlen D Meyers, MD, MBA, Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine Author and Editor Disclosure Synonyms and related keywords: snoring and obstructive sleep apnea, adjustable oral appliance, OA, dental appliance, oral device, dental device, jaw thrust device, Thornton anterior positioner, TAP sleep apnea device, OSA, sleep disorder, sleep-disordered breathing, SDB, upper airway resistance syndrome, UARS INTRODUCTION AND PHYSIOLOGYSection 2 of 11
  Sleep-disordered breathing (SDB), with its associated medical problems, places an enormous financial burden on society. Because of the prevalence of this condition, cost-effective management is essential. Fortunately, a number of viable options are available. The most common initial treatment for SDB is a continuous positive airway pressure (CPAP) device. CPAP is effective only for patients who can tolerate the device and unfortunately, affords no permanent cure. Surgical intervention is the second form of treatment and involves anatomical alteration of the airway. Although more expensive from the outset, it is a permanent option for treatment results in permanent alteration of the airway. CPAP devices can prove annoying to many patients and may be entirely ineffective in others. Additionally, the prospect of surgery may not appeal to all patients. Prosthetic devices are available as effective and low-cost treatment options for many patients. Although primary hypoventilation may be an underlying cause of SDB, the most important factor lies in obstruction of the upper airway. Generally, obstruction of the airway may be found at 3 primary sites (ie, nose, velopharynx, hypopharynx). During normal awake respiration, the obstructive tendency of the negative inspiratory pressure within the upper airway is balanced by the outward force of pharyngeal dilator muscle activity under central nervous system control. Reduction of tone in this musculature and loss of compensatory reflex dilator mechanisms result in obstruction during sleep. Snoring, a common symptom of SDB, is a repetitive sound caused by vibration of upper airway structures during sleep. Patients who have obstructive sleep apnea generally have smaller upper airways than normal due to increased parapharyngeal fat, a large tongue, an elongated palate, or thickened lateral pharyngeal walls. The thickened lateral pharyngeal walls explain why the upper airways of some apneic patients may be directed anteroposteriorly, as opposed to the normal lateral orientation, forcing these muscles to act at a disadvantage. Lateral pharyngeal wall encroachment by the peritonsillar pillars is also an important etiology of obstructive sleep apnea. Greater pharyngeal length increases collapsibility, which may explain why men are more susceptible to obstructive sleep apnea than women. Hundreds of devices have been patented for treatment of snoring and sleep apnea, with the intent of directly or indirectly opening the airway. This article discusses general principles involved and primarily discusses the most effective prosthetic devices in controlling SDB, which are adjustable oral appliances (OAs). Presenting signs and symptoms/Physical exam
POSITIONING AND NASAL AIRWAYSection 3 of 11
Positioning of the patient during sleep is a useful method to control simple snoring. Snoring is often resolved when the patient assumes a nonsupine position. The physiology is intuitively simple: the soft palate and tongue fall posteriorly due to gravity and relaxation of the genioglossus. When the mouth opens, the tongue is even more retrodisplaced. Airway obstruction results in subsequent oxyhemoglobin desaturation if apnea occurs. The effect of positioning is demonstrated by polysomnogram, which usually shows more frequent and severe disordered breathing events when the patient is supine. In mild cases, nonsupine positioning may relieve the obstruction. The classic remedy of attaching a tennis ball to the back of the individual's pajamas actually may help some patients. However, most patients with significant SDB show apnea in all positions; thus, this technique is seldom useful for patients with more than simple snoring. A snoring pillow may help some patients with snoring problems. Used appropriately, it positions the head so that the mouth is closed and the jaw is held forward. Unfortunately, movement during sleep minimizes the pillow's effectiveness. In the normal airway, the limen nasi is the site of the highest resistance to airflow. Collapsed alae, a severely deviated septum, or hypertrophied turbinates may affect airflow substantially. It has been demonstrated that nasal valve surgery improves snoring for many patients whose primary problem is nasal airway obstruction. Although surgical therapy is effective for treating nasal valve obstruction, devices that splay the alae (externally or internally) have also demonstrated success in improving nasal airflow and decreasing snoring. Studies disagree on whether significant improvement occurs. While anecdotal reports describe patients whose sleep apnea may have been controlled by alar splaying devices, no statistical difference in patients using the devices compared to controls has been demonstrated. These devices are benign, inexpensive, and available at any pharmacy. For patients with minimal problems and noticeable nasal airway obstruction, devices that splay the alae are easy to obtain and test. Nasal trumpets may be useful for short-term management in select patients. Trumpets commonly are employed in postanesthesia airway management. They bypass any nasal, soft palate, and, often, tongue base obstructions. However, few patients are willing to use the trumpets nightly to control SDB. ORAL APPLIANCESSection 4 of 11
Patients with significant SDB almost always have some component of soft palate or tongue base obstruction (typically both). A number of oral appliances (OA) have been developed over the years to treat snoring and obstructive sleep apnea. Wide varieties of OAs exist and are made to address the entire range of pathological processes resulting in apnea. OAs can advance the soft palate, tongue, or mandible, thus opening the airway. Those that advance the soft palate seldom are employed, most likely because of gag, discomfort, and the success of laser and radio frequency soft-palate procedures. Probably for similar reasons, and because of the success of adjustable OAs, devices that advance the tongue alone rarely are used. During obstructive apneas, the collapsed pharynx prevents airflow, which leads to continued negative pressure generated by respiratory efforts. The vicious cycle continues until the patient is aroused. Traditional devices work by downwardly rotating, and in some cases advancing, the mandible. By altering the position of upper airway structures, these devices serve to enlarge the airway and/or reduce collapsibility. OAs that fixate and/or alter the relative position of the mandible to the maxilla affect the pharyngeal soft tissues by increasing the airway space, stabilizing the mandible in an anterior and closed position, advancing the tongue, and increasing genioglossus muscle activity. Variations in design include restricted elastic bands, clasps, or tubes for opening the mouth. These modifications act to relieve pressure and produce posterior extension of the maxillary component so as to modify the position of the soft palate or tongue. Dental impressions are generally required for mandibular advancing devices and anterior tongue retainers; however, prefabricated models can now be found. Proper fitting and alignment as well as regular patient follow-up are important components of therapy. Compared to other treatment modalities, OA therapy has several advantages, including simplicity, reversibility, cost-effectiveness, and broad applicability for varying degrees of SDB. An OA can be used to treat simple snoring, upper airway resistance syndrome (UARS), and full-blown obstructive sleep apnea (OSA). OA therapy offers the most logical way to initiate treatment in most cases as it is readily accepted by most patients. It can also be used in conjunction with other forms of treatment. To date, more than 40 different OAs have been patented. They can be divided into 2 basic categories, fixed OAs and adjustable OAs. Each group can be subdivided into noncustom devices (ie, mass produced/one-size-fits-all) and custom devices (ie, fabricated from specific patient impressions). While most appliances superficially appear similar because they share the same physiologic principles, they are actually quite different due to basic design features. The advantages of OAs over other sleep apnea treatment options include relatively low cost, good success rates (efficacy comparable to uvulopalatopharyngoplasty [UPPP] but less efficacious than CPAP), increased rates of compliance (ranging from 50-100%, more preferred than CPAP), a more benign adverse-effect profile, rapid effect, and easy termination without sequelae. Additionally, OA insertion can be performed as a single-stage procedure in an outpatient setting. OAs are recommended for mild-to-moderate obstructive sleep apnea and in patients with BMIs less than or equal to 30 who fail or cannot tolerate CPAP. A new treatment option is the Pillar Palatal Implant. Treatment involves the placement of three mesh polyethylene terephthalate implants, 18mmx2mm each, within the soft palate muscles under local anesthesia. These permanent implants serve to stiffen the palate, thus decreasing vibration or movement to improve snoring and obstructive sleep apnea. FEATURES AFFECTING THE SUCCESS OF ORAL APPLIANCESSection 5 of 11
Retention OAs must fit accurately, comfortably, and remain in position all night. Some OAs are made of hard acrylics that wedge against the height of contour of each tooth. Rigid OAs periodically require realigning, which is a labor-intensive process. If the patient neglects realigning and continues to wear the device, movement and misalignment of teeth can occur. Some appliances use orthodontic retentive mechanisms (ie, ball clasps, Adams clasps) that use undercuts on a select number of teeth. Since only a few, usually interproximal, areas are involved (typically 4 in each arch), movement of teeth frequently occurs. Recently, heat-sensitive elastomeric materials have been used. These materials have proven to be the most effective in OA retention. They allow contact with more dental surface area, including undercuts and portions of interproximal areas resulting in a more uniform fit and higher rates of appliance retention. Most noncustom OAs are made of soft boil-and-bite elastometrics that usually fail to maintain adequate retention for long when expected to attach to both maxillary and mandibular dentitions. Although Pillar implants are a relatively newer modality, short term studies have shown good retention. One long term study demonstrated a 17.8% partial extrusion rate. Adjustability OAs should be able to variably adjust mandibular position. Many methods are available, such as interchangeable shims, incremental slots, and rotational mechanisms. Both shim and slot methods can be limiting due to the distance required of the mandible (seldom <1 mm and often 2 mm), which may initiate muscular and/or joint sensitivity. Increments this large may jeopardize clinicians' ability to optimize treatment. Increased efficacy can be achieved with a rotational mechanism that allows for more precise positioning of the mandible. Pillar implants are not adjustable, and once inserted should remain in place. Adaptability OAs must be adaptable to dentition changes (ie, fillings, crowns). Pillar implants are placed into the soft palate, near the junction of the hard palate. Consequently, they are adaptable to all patients without palate clefts or fistulas. Factors that influence a positive outcome with OAs include younger age, lower BMI, smaller neck size, positional OSAHS, and lower AHI. INDICATIONS AND CONTRAINDICATIONSSection 6 of 11
OAs are indicated for patients with the following:
OAs are contraindicated for patients with the following:
Close collaboration with a dentist is recommended. Tongue position and tonsil size can influence the success of the Pillar implants; however, no other contraindications have been identified to date. TREATMENT SEQUENCE AND ASSOCIATED PROBLEMSSection 7 of 11
Treatment begins with initial consult and examination. Acquire available dental records. Thoroughly instruct the patient in OA use and care and follow up in 2-4 weeks. An objective analysis of progress includes pulse oximetry and polysomnogram. Follow-up at 6-month intervals for as long as the OA is used is recommended to check status of the patient, dentition, and device. Expected sequelae or problems Some patients may be unable to tolerate OAs. Many develop temporary adverse sensitivities of teeth, mastication muscles, and TMJD. Consider these problems a normal part of insertion, adjustment, and removal transition phases that should improve with time. Temporary bite changes after removal of the device last 5-60 minutes. Such changes always should resolve in a reasonable time with no discomfort. Some patients experience increased salivary production. Individuals who breathe through their mouths often experience dry mouth. Pillar implants may extrude over time, although the frequency of this occurrence is low (less than 1% according to the manufacturer). The inflammatory reaction that ensues after insertion usually binds the three implants together and stabilizes their positions permanently. Possible adverse effects Many unusual problems may develop with the fitting or use of an OA. Complications often are prevented from becoming significant issues by simple recognition of their possibility and appropriate response to initial complaints. Possible adverse effects include the following:
Furthermore, the risk of worsening upper airway function (ie, worse apnea-hypopnea frequency), though rare, should be considered. Long-term consequences of oral appliance use are not well studied, but it is suggested that permanent tooth movement causing change in mandibular posture is common. Adverse effects specific to soft palate implants include difficulty speaking or swallowing and ear or jaw pain, all secondary to initial post-procedural swelling. These implants may also be extruded requiring replacement. Conditions and situations affecting long-term oral appliance success As weight increases, SDB symptoms intensify. With weight loss, SDB symptoms diminish. With age, muscles in the pharyngeal area atrophy, thus increasing obstruction. Congestion and sinus drainage contribute to nasal and pharyngeal inflammation, constricting the airway and aggravating SDB. CNS depressants and muscle relaxants may have a counterproductive sedative or relaxant effect. Proper sleep hygiene is desirable, with 8 hours total sleep time considered optimal. Maintenance of a consistent sleep schedule also mitigates problems. Obstruction is more prevalent in a supine position. Environmental factors (eg, temperature, lighting, noise, comfort) affect quality and length of sleep. CLINICAL TRIALSSection 8 of 11
OAs are most successful in controlling simple snoring, UARS, and mild-to-moderate OSA. Improvement of snoring occurs in a high proportion of patients, with complete resolution in a smaller subset. A large literature review by Lowe showed that, as a group, OAs were effective in mild-to-moderate OSA with a 75% compliance rate. A recent study on the Thornton anterior positioner (TAP) demonstrated effectiveness of the adjustable device. In this study, 75 patients were evaluated by polysomnogram, with and without the appliance. A responder was defined as having an apnea/hypopnea index (AHI) lower than 10 with the device. In 38 of 75 patients, OSA was abolished with the device alone. In an additional 31 patients, the AHI was reduced from 54 ± 31 to 20 ± 12. Three snorers without apnea had unchanged scores. Univariate regression analysis showed an inverse correlation between percent improvement of AHI and both baseline AHI and body mass index (BMI). No correlation with age was noted. Responders had a baseline AHI of 39 ± 21, while nonresponders had a baseline AHI of 54 ± 31. Baseline low-oxygen saturations were similar (78 ± 15 vs 78 ± 12), but responders improved to 89 ± 5, while nonresponders had no significant change. These findings confirm that the TAP works best in patients with mild-to-moderate SDB. (Note that all treatments yielded best results in patients with mild disease). In this study, 86% of patients continued to use the appliance after a mean follow-up time of 350 days. These patients were very satisfied (60%) or moderately satisfied (27%) with the device. Complications occurred in 26% of patients but were minor and expected (eg, tooth and/or jaw discomfort, excess salivation). The impact of OAs on obstructive sleep apnea is significant. A recent study, Apnea Hypopnea Index (AHI) values were reduced by approximately 56% in nearly 70% of patients. Treatment success is likely related to initial AHI and body weight. Nighttime sleep and daytime sleepiness also appear to benefit from use of OAs. Subjective improvements in snoring are reported in most case series with oral appliances, where approximately 50% achieve an AHI less than 10, and patient-reported compliance rates are 75% to 90%. One study assessed the efficacy of Pillar implants in patients with socially significant snoring, without a history of obstructive sleep apnea. The outcome was assessed by the change in snoring severity measured by the bed partner using a 10-centimeter visual analog scale, with 10 representing snoring that was unbearable. Snoring, rated by the bed partner, had a baseline mean value of 8.5, which decreased to 5 at 30 days and 4.4 at 90 days post-treatment. All patients tolerated the procedure well. At 90 days, 75% of patients and 90% of their bed partners advocated the procedure. Clinical trials assessing the efficacy of Pillar implants in obstructive sleep apnea demonstrated that 81% of patients achieved reductions in AHI values. Nearly 60% of patients achieved resolution of apnea. At this time, pillar implants appear to be just as efficacious as uvulopalatopharyngoplasty for the treatment of mild-to-moderate sleep apnea. Further studies regarding the efficacy of Pillar implants in OSA are required. CONCLUSIONSection 9 of 11
Millions of Americans are affected by sleep disordered breathing. Various treatments are available, depending on disease severity, patient anatomy, and natural inclination regarding treatment options. Some patients are claustrophobic and cannot use CPAP but can tolerate OAs. Others may fear surgery or simply want surgery as the last option. OAs are simple, effective, and inexpensive and should be considered as potential treatment by any otolaryngologist who treats patients with snoring or sleep apnea. MULTIMEDIASection 10 of 11
REFERENCESSection 11 of 11
Snoring and Obstructive Sleep Apnea, Prosthetic Management excerpt Article Last Updated: Jun 28, 2007 | ||||||||||||||
