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FACT SHEET: Obstructive Sleep Apnea (also known as “OSA”, “obstructive sleep apnea syndrome” [“OSAS”], and “obstructive sleep apnea-hypopnea” [“OSAH”])

Date of Publication: June 20, 2019

Is the initiation of non-invasive dental hygiene procedures* contra-indicated?

  • No.

Is medical consult advised?

  • Yes, if previously undiagnosed sleep apnea is suspected or if previously diagnosed sleep apnea is poorly managed.1
  • No, if sleep apnea is well managed.

Is the initiation of invasive dental hygiene procedures contra-indicated?**

  • No.

Is medical consult advised?

  • See above.

Is medical clearance required?

  • No.

Is antibiotic prophylaxis required?

  • No.

Is postponing treatment advised?

  • No, not typically, unless co-morbid conditions pose a potential safety risk.

Oral management implications

  • The oral health professional plays an important role in identifying patients/clients who should be assessed by sleep specialists.2 In conjunction with other healthcare providers (e.g., dentists and physicians), the dental hygienist may also play a role in monitoring and treatment.
  • Patients/clients who have been diagnosed with OSA require treatment3, not only to alleviate snoring and sleepiness but also to prevent and treat the numerous adverse health effects associated with the condition. For example, treatment of OSA may reduce or eliminate bruxism during sleep.
  • Oral appliances are a primary treatment option for OSA4, as well as an option for patients/clients unable or unwilling to use positive airway pressure approaches. These devices mechanically increase the volume of the upper airway in the retroglossal and retropalatal areas, and adjustable dental appliances are generally better than fixed appliances. The two main types of oral appliances are mandibular advancement devices (MADs, which engage the mandible and reposition it – and indirectly the tongue – in an anterior and forward position) and tongue-retaining devices (TRDs, which directly engage the tongue and hold it in a forward position). The more commonly used MADs are usually made of acrylic resin and are composed of two pieces that cover the upper and lower dental arches. TRDs are typically made of silicone in the shape of a bulb or cavity; the tongue is stuck into the bulb, which is then squeezed and released to create suction that hold the tongue forward.
  • While oral appliances are generally well tolerated, adverse effects are common even if most are minor and transient and resolve rapidly with removal of the device. Such adverse effects include temporomandibular joint (TMJ) pain, TMJ sounds, muscular pain, tooth pain, hypersalivation, gum irritation, xerostomia, temporary chewing problems, and morning-after or permanent occlusal changes (e.g., tooth movement resulting in posterior open bite and/or decreased anterior overjet).
  • Persistent occlusal changes secondary to oral appliance use include proinclination of the mandibular incisors, retroinclination of the maxillary incisors, and a posterior open bite. Orthodontic restorative treatment may subsequently be required.
  • Surgery is a treatment option for patients/clients with OSA when noninvasive treatments such as CPAP or oral appliances have been unsuccessful or are inappropriate. Surgery can correct an obvious anatomic deformity that causes breathing problems; most surgical options, however, involve reduction or removal of tissue from the soft palate, uvula, palantine tonsils, adenoids, or tongue.5 More complex surgery may be employed to adjust craniofacial bone structures.
  • Some patients/clients who undergo UPPP surgery experience nasal regurgitation (i.e., fluids going up the nose when swallowing).
  • In addition to tonsillectomy and adenoidectomy, children with OSA may benefit from: orthodontic treatment; rapid maxillary expansion; or transverse palatal expansion6.

Oral manifestations

  • The underlying defect in sleep-related disorders, including OSA, is an anatomically narrowed upper airway combined with abnormal pharyngeal dilator muscle collapsibility7. Anatomic narrowing may occur at any site in the upper airway from the nasal cavity to the larynx, with many patients/clients affected by OSA having more than one site of obstruction. In the oropharynx, narrowing may be caused by an enlarged tongue, mandibular retrognathia (i.e., abnormal posterior positioning of mandible), excessive lymphoid tissue, large palantine tonsils, or redundant retroglossal folds. In the nasopharynx, narrowing may be due to hypertrophic adenoid tonsils, an elongated soft palate, and an elongated and edematous uvula.
  • Adenotonsillar hypertrophy is the most common cause of upper airway obstruction in children.
  • Tumours or birth defects involving the mandible or tongue may be contributing factors.
  • Edentulism is associated with elevated rates of OAS, because it can cause a reduction of lower face height, anterior rotation of the mandible, and an unnatural position of the tongue.
  • About 45% of patients/clients with Down syndrome have obstructive sleep apnea due to their flattened midfaces, narrowed nasopharyngeal areas, reduced tone of muscles of the upper airways, and enlarged tongues, tonsils, and adenoids.
  • Persons with acromegaly8 are at risk of OSA due to increased size of the tongue, swelling of the throat, and changes in the facial bones.
  • Patients/clients with cleft palate or cleft lip are at elevated risk of OSA due to altered facial bone structure, and the tongue may also sit further back in the mouth. Similarly, persons with a receding chin are at increased risk.
  • Sleep bruxism can is associated with sleep apnea, because clenching of the teeth may expand the airway and possibly reduce blockage. Thus, patients/clients with OSA may display signs of bruxism, including worn tooth enamel, fractured teeth, tooth pain and sensitivity, and/or masseter muscle soreness.
  • Other intraoral signs associated with OSA include redness of the soft palate and uvula area, narrow palate, and torus mandibularis (>2 cm on both sides of lower mandible).
  • Other associated symptoms include dry mouth.
  • Enamel erosion attributable to gastroesophageal reflux disease (GERD) can occur.

Related signs and symptoms

  • OSA is a common sleep disorder9 characterized by loud snoring and excessive daytime sleepiness in conjunction with episodes of apnea (complete cessation of breathing) or hypopnea (significantly decreased ventilation), which result from airway obstruction during sleep. Most pauses in breathing last between 10 and 30 seconds, but may persist for one minute or more and cause abrupt reductions in blood oxygenation saturation. The brain responds to lack of oxygen by causing a brief arousal from sleep to restore normal breathing. Sleep quality worsens as the frequency of arousals during the night increases, and fragmentation of sleep pattern occurs.10
  • Between 2% and 4% of the middle-aged adult population aged 30 to 60 years is estimated to be affected by OSA, with males affected more than females. However, prevalence increases substantially with age, with up to 67% of elderly men and 54% of elderly women affected. In children, prevalence is estimated at 3%, with highest occurrence between the ages of 2 and 5 years. Persons of black, Hispanic, and Pacific Islander background are at increased risk.
  • Factors that can contribute to enlargement of upper airway soft tissues in apneic patients/clients include: obesity (particularly large neck circumference); vibration trauma of the uvula; edema secondary to negative pressures; and, possibly, genetics. Other risk factors for OSA are deviated nasal septum, nocturnal nasal congestion (due to rhinitis or abnormal morphology), natural or premature aging, temporary or permanent brain injury, hypothyroidism, polycystic ovary syndrome (PCOS), acromegaly, and smoking11.
  • Because OSA only happens during sleep, many persons who are afflicted with this condition aren’t aware of their disorder and often go undiagnosed or experience significant delay in diagnosis. The link between excessive daytime sleepiness and its potential underlying cause of OSA often isn’t made.
  • Snoring, snorting, gasping, and breath holding are signs often described by the bed partner or parent of a patient/client with OSA12.
  • Snoring is the most common sign in patients/clients with OSA, with virtually all persons with OSA being snorers13.
  • Hypoxia, anoxia, and hypercapnia (elevated carbon dioxide level in the blood) may occur, depending on the degree and duration of airway obstruction.
  • Neurocognitive effects of OSA due to chronic sleep deprivation include sleepiness, irritability, anxiety, decreased alertness, poor concentration, decreased libido, memory loss, and headaches (particularly morning headaches). In turn, these deficits can contribute to poor job performance, relationship discord, and driving impairment.
  • Cardiovascular effects associated with OSA include hypertension, stroke, heart failure, pulmonary hypertension, and cardiac arrhythmias. OSA has also been linked to poor asthma control.
  • In children with obstructive sleep apnea and heart disease (e.g., children with Down syndrome), low blood oxygenation can result in pulmonary hypertension, which in turn can cause the right side of the heart to become enlarged with attendant complications such as heart failure.
  • Overall mortality rate from all causes is increased among patients/clients with untreated OSA in proportion to severity.

References and sources of more detailed information

Date: September 10, 2018
Revised: May 17, 2023


1 Definitive diagnosis of sleep-related breathing disorders can be made by polysomnography, in which the patient/client’s breathing, brain waves, and other activity are recorded during sleep in a laboratory setting (“sleep lab”). There are also portable home sleep apnea testing (HSAT) devices that measure oxygen levels, airflow through the nose and mouth, breathing patterns, and snoring. Sleep apnea is graded according to how frequently breathing stops (i.e., occurrence of “apneas” or “hypopneas” as recorded in the apnea-hypopnea index); mild = 5 to 14 episodes per hour, moderate = 15 to 29 episodes per hour, and severe = 30 or more episodes per hour. In contradistinction to obstructive sleep apnea, central sleep apnea (which is not as common as OSA) results from the brain temporarily ceasing to send nerve impulses to the muscles of breathing (such as in: brainstem dysfunction resulting from infection, stroke, trauma, or congenital abnormality; neuromuscular conditions [e.g., amyotrophic lateral sclerosis and myasthenia gravis]; severe obesity; narcotic use; or high altitude) — the airway is normal, not obstructed. In mixed (complex) sleep apnea, the patient/client has a blend of both obstructive and central sleep apnea.
2 Flagging of possible medical referral can be facilitated by including 2 questions in the medical questionnaire; namely, “do you snore loudly” and “do you have difficulty staying awake when you are inactive”. The more formalized STOP questionnaire (for which 2 “yes” answers should prompt medical referral) comprises 4 questions; namely, “do you snore loudly”, “do you often feel tired, fatigued or sleepy during daytime”, “has anyone observed you stop breathing during sleep”, and “do you have or are you being treated for high blood pressure”. The increasingly used STOP-Bang questionnaire augments STOP with the addition of four other parameters: “body mass index greater than 35 kg/m2”, “age older than 50”, “neck size large” (is your shirt collar 40 cm or larger), and “gender = male”.
3 Treatment of OSA comprises 4 different approaches; namely, behavioral modification (e.g., weight loss, regular aerobic exercise, regular sleep hours, throat/perioral/tongue exercises, nasal dilator strips [which may reduce snoring without also treating OSA], nasal decongestants and/or topical corticosteroids, antidepressants, avoidance of supine position while sleeping [i.e., sleep on side rather than back], avoidance of alcohol/sedatives/muscle relaxants near bedtime, and smoking cessation); positive airway pressure (i.e., delivery of positive airway pressure [PAP] to the patient/client’s airway during sleep by an air compressor via nasal tubing or full face mask; delivery of PAP may be accomplished by continuous positive airway pressure [CPAP, the most common method], bilevel positive airway pressure [BiPAP or BPAP], or automatic [auto-adjusting] positive airway pressure [APAP]); oral appliances; and surgery.
4 Prior to the prescribing or constructing of a snoring appliance by a dentist, the patient/client should be referred for medical assessment to determine the presence and severity of OSA. This assessment should either confirm that snoring may be treated independently by the dentist or that treatment should occur in cooperation with an attending physician because OSA is involved.
5 Specific surgical approaches (with varying success rates) to treat OSA include: tonsillectomy; adenoidectomy; tracheostomy (almost uniformly effective in curing OSA, but usually unacceptable to patients/clients); nasal septoplasty; nasal turbinate reduction; uvulopalatopharyngoplasty (UPPP, in which the uvula and tonsils are excised along with the soft palate being trimmed), which is the surgical procedure most commonly performed to correct OSA, although with a success rate of < 50%); laser-assisted uvulopalatoplasty (LAUP, which research has found not to be effective); radiofrequency volumetric tissue reduction (RVTR); genioglossus advancement-hyoid myotomy and suspension (GAHMS); pillar implants; tongue base reduction; maxillary and mandibular advancement osteotomy (MMO; also known as maxillomandibular advancement [MMA]); and bariatric surgery (e.g., gastric bypass, sleeve, or band. Removal of the adenoids and palatine tonsils is highly successful in treating OSA in children.
6 Transverse palatal expansion is a nonsurgical procedure in which a screw device is temporarily attached to the maxillary teeth and tightened progressively to widen the halves of the upper jaw in which the halves are still separate.
7 Abnormal pharyngeal dilator muscle collapse involves both dynamic and static factors. These include: tissue volume; changes in the adhesive character of mucosal surfaces; changes in jaw and neck posture; decreased tracheal tug; effects of gravity; and decreased intraluminal pressure that results from increased resistance in the nasal cavity and pharynx.
8 Acromegaly is caused by excessive levels of growth hormone during adulthood. Enlargement of the bones of the hands and feet is also a feature.
9 Obstructive sleep apnea exists along a clinical spectrum of sleep-related breathing disorders, with snoring and upper airway resistance syndrome being less serious, and obesity hypoventilation syndrome (Pickwickian syndrome) being more serious. Depending on the extent of upper airway narrowing, increased resistance to airflow may manifest as vibration of soft tissues (i.e., snoring), reduced ventilation (i.e., hypopnea), or complete obstruction (i.e., apnea).
10 Fragmentation of sleep pattern involves disruption of the phases of non-rapid eye movement [NREM] and rapid eye movement [REM] sleep.
11 Smoking causes inflammation and fluid retention in the upper airway.
12 The most useful predictors of OSA are witnessed apneas, excessive daytime sleepiness, body mass index (BMI) above 30 (or 35 according to some sources), male gender, and neck circumference greater than 40 cm.
13 Most persons who snore, however, do not have OSA. Habitual snoring prevalence is about 44% of men and 28% of women.

* Includes oral hygiene instruction, fitting a mouth guard, taking an impression, etc.
** Ontario Regulation 501/07 made under the Dental Hygiene Act, 1991. Invasive dental hygiene procedures are scaling teeth and root planing, including curetting surrounding tissue.