Sleep apnea oral appliances are noninvasive and generally well tolerated. The use of an oral appliance (OA) is preferred when, for some reason, CPAP therapy is not appropriate or the patient is unfavorable to Continuous Positive Airway Pressure therapy. The success and, secondarily, compliance with sleep apnea oral appliance treatment can be influenced by several factors, such as obesity, the severity of sleep apnea, and facial structures.
In most cases, the assessment of sleep apnea oral appliance usage time is based on patients’ own reporting. Some studies found no differences in oral appliance usage rates compared to CPAP when looking at usage nights per week or hours per night. In a comparative study, it was found that the CPAP device was used less than the sleep apnea oral appliance. If sleep apnea should be treated for at least 4 hours a night to achieve an effective response, 43% of study patients using the CPAP device and 76% of sleep apnea oral appliance patients received an adequate response. Based on patient self-reported use rates, sleep apnea oral appliance is used more than CPAP, but results may be inaccurate due to over-reporting of patient sleep apnea oral appliance use.
Patients who are less overweight and have less severe symptoms generally prefer sleep apnea oral appliance treatment compared to CPAP, but there is a lot of variation in the studies. In the review article, patients chose sleep apnea oral appliance at the end of the study period instead of CPAP in four of the six studies. However, there are studies in which patients chose CPAP as a better option than the sleep apnea oral appliance and, on the other hand, studies in which compliance with treatment was similar for both treatments. The sleep apnea oral appliance has been favored by patients with less overweight and milder symptoms of sleep apnea, according to this study. A five-year follow-up study found that patients with mild sleep apnea were most likely to continue oral appliance therapy compared to study patients with more severe forms of the disease. Of the non-apneoic snorers in the study, 78% and 74% of those with mild sleep apnea continued on long-term usage of sleep apnea oral appliance.
Patients using CPAP and a sleep apnea oral appliance have reported similar factors complicating device use, but these vary by treatment. The main factors that have influenced the choice of treatment are its effectiveness, portability, cost, treatment inconvenience, spouse approval or disruption, availability of electricity and water, comfort of the device, and effects on bite. The choice of treatment is also influenced by the patient’s personality, lifestyle and possible sense of shame about the disease. However, the effectiveness of treatment was considered to be the most important of the above factors.
The survey found that patients most often miss sleep apnea treatment due to the inconvenience and annoyance of using the device. The second most common reason for discontinuation of treatment is its ineffectiveness in the treatment of sleep apnea symptoms. This was partly explained by the fact that the study involved people with severe sleep apnea treated with a sleep apnea oral appliance. Typical sleep apnea oral appliance side effects remained secondary reasons for discontinuation of treatment. However, 76% of sleep apnea oral appliance users reported using the device one year after starting treatment and 62% after four years. After five years of initiating sleep apnea oral appliance therapy, 91% of patients report using the mouthpiece for more than four nights a week for at least half of the night.
Sleep apnea oral appliance side effects in short and long term use
Sleep apnea oral appliance treatment is associated with both short- and long-acting side effects such as increased salivation, feeling of dry mouth, jaw joint tenderness, jaw stiffness in the morning, toothache, gingival and mucosal sensitivity, headaches, and in some cases even altered bite. The changes in the bite are the result of the device taking its retention from the teeth and alveolar ridge to which the resistance caused by the bite muscles is applied. The number of reported side effects in patients using a sleep apnea rail varies widely, probably due to the type of device, the bite before starting treatment, the level of oral hygiene, and the duration of treatment. Side effects are usually transient, lasting an average of two months after the introduction of a sleep apnea mouthpiece. If dry mouth, jaw joint symptoms or other side effects continue after this, the risk of stopping treatment increases significantly.
Oral appliance causes bite changes?
The most problematic of the long-term side effects are tooth displacement and bite changes. This is the result of a mouthpiece-induced backward force on the upper incisors and a forward force on the lower incisors. The changes occur over a long period of time and are relative to the amount of use. As a result of teeth tilting, the lower tooth arch has also been observed to widen, leading to an increase in the distance between the canines and cheek teeth.
Within two years of starting treatment, a significant reduction in the number of horizontal and vertical overbites and bite pairs has been observed in the bite. The decrease in bite contacts also results in a decrease in bite force, which has been observed in short- and long-term studies. The change in bite progresses progressively with the use of the mouthpiece. For about a third of the oral appliance users, the change in horizontal bite is more than 1 mm. In a 17-year follow-up study, the average change in horizontal overbite was -1.1 mm and in vertical overbite -1.6 mm. The largest measured change in horizontal overbite was -5 mm and in vertical overbite -4 mm in different patients. In a recent study, a flexible sleep apnea oral appliance that does not cover tooth surfaces has been found to cause lower teeth to tilt in particular compared to a rigid sleep apnea oral appliance that covers teeth.
The change in tooth position in those using the flexible sleep apnea device was 0.3 mm, while no change in the location of the lower incisors was observed in those using the rigid oral appliance. On the other hand, in an older follow-up study, no changes in overbite during oral appliance treatment were observed at the four-year follow-up. Participants in the study used a sleep apnea device in which the coverage of the buccal surfaces of the upper incisors was less than normal and the lower part covering the incisors was reinforced.
However, it has been found that in almost all patients using a sleep apnea rail, a change in overbite can be observed within five years of starting rail therapy. This change is usually negligible and in more than half of the patients the bite changes in a better direction than at before. For most, the changes do not cause harm, but some may suffer from a change in bite for functional or aesthetic reasons. A change in bite can also affect the effectiveness of sleep apnea oral appliance treatment as the degree of lower jaw forward import decreases as a result of the change in bite. This can reduce the effectiveness of treatment and affect patient compliance.
The response to treatment caused by the forward import of the lower jaw is individual, so the effects on the outcome of the treatment resulting from the change in the bite should also be assessed on a patient-by-patient basis. In general, patients adapt to a slow change in bite. Bone changes can also be seen in those who have used a sleep apnea mouthpiece for a long time. The lower face height has been observed to increase and the mandible to rotate downward.
Temporomandibular disorders (TDM) caused by an oral appliance
In addition to dental side effects, the sleep apnea oral appliance can cause pain and dysfunctional symptoms (TMD / temporomandibular disorders) in the temporomandibular region. Pain conditions and disorders of the jaw joint area decrease over time and disappear completely within 6-12 months in most patients. A two-year follow-up study also found that jaw joint symptoms were predominantly transient. At the start of treatment, 24% of those using a sleep apnea oral appliance and 6% of those using CPAP reported experiencing symptoms of TMD. However these symptoms did not worsen or result in treatment discontinuation in either group during follow-up. Because jaw joint symptoms are usually transient, they cannot be considered a contraindication to continued oral appliance therapy.
There have been very few long-term studies on the development of jaw joint or facial pain. In a five-year follow-up study, 25% of enrolled patients had symptoms of TMD prior to treatment and were diagnosed according to the RDC / TMD (Research diagnostic criteria for temporomandibular disorders) classification and were divided into three groups: myofascial pain, reversible disc dislocation, and arthralgia. During the five-year follow-up, the incidence of TMD symptoms was not observed to increase with sleep apnea oral appliance treatment. Jaw joint symptoms were only initially reported in patients with myofascial pain and arthalgia. No one interrupted treatment due to pain, but some of them discontinued it due to the ineffectiveness of mouthpiece therapy.
Follow-up of sleep apnea oral appliance treatment
After preparation of the custom made sleep apnea oral appliance it is good to control the use of the device annually. Control visits monitor the effects of the mouthpiece on the bite (record the Angle class and overbites) and the condition of both the jaw joints and the oral appliance itself. The controls take into account the side effects of the mouthpiece in both short-term and long-term monitoring. It is also important to motivate the patient to use the sleep apnea oral appliance and discuss the subjective response of the oral appliance so that the patient feels the need for treatment. The objective response can be determined by polysomnography examination while the patient is sleeping with the rail mouthpiece. According to the recommendations, in cases of at least moderate sleep apnea, a sleep registration study with the sleep apnea oral appliance is necessary when evaluating the results of treatment. Based on the study, a decision is made to either continue sleep apnea oral appliance treatment or, if necessary, refer the patient forward to plan a more appropriate treatment.
Review of the patient’s treatment history, oral clinical examination, selection of the right mouthpiece type, and rapid observation of side effects are key factors in the success of oral appliance care. Patients’ bites should be monitored frequently to assess the effects on treatment effectiveness and oral health.
Sleep apnea oral appliance (OA) abstract
Sleep apnea oral appliancetreatment has become more common in the treatment of obstructive sleep apnea and snoring in the last decade, but very few dentists have knowledge of sleep apnea oral appliance treatment and treatment monitoring. Although CPAP therapy remains the most effective and used form of treatment for sleep apnea, the sleep apnea oral appliance provides a viable alternative to or in addition to CPAP in properly selected patients. In patients with mild to moderate sleep apnea, the use of a sleep apnea oral appliance reduces AHI, improves oxygen saturation, and may alleviate daytime fatigue. The sleep apnea oral appliance also has a lowering effect on blood pressure. The sleep apnea oral appliance is easy to take with you on the trip and its use does not require electricity or water.