Sleep-related Breathing Disorders and Bruxism
Sleep-related breathing disorders is an umbrella term used to describe disorders related to abnormal breathing during sleep where breathing is repeatedly disrupted. Bruxism is a common sleep-related movement disorder characterised by jaw clenching or teeth grinding.
Snoring is the noise made when smooth air movement during sleep is intermittently interrupted by the partial collapse and vibration of soft tissues in the upper airway. Snoring may not only be socially embarrassing but could be a signal that the individual may be suffering from a more sinister medical disorder known as Obstructive Sleep Apnea (OSA).
Obstructive Sleep Apnea (OSA)
For those suffering from OSA, excessive daytime sleepiness due to fragmented sleep is but one reason for treatment (Take the Epworth Sleepiness Scale here). Apneics are also more likely to develop heart problems, strokes and have a higher rate of driving-related accidents. Few realise that it’s also a common cause of nocturnal polyuria and erectile dysfunction in men.
Upper Airway Resistance Syndrome (UARS)
Upper Airway Resistance Syndrome is not as well known as OSA but is perhaps more relevant to children and female clientele.
Unlike OSA, there is no high male-to-female ratio in UARS. In our experience, women with autonomic dysfunction (e.g. orthostatic hypotension, very low blood pressure, cold extremities) and children with ENT issues (sinusitis, enlarged adenoids/tonsils, allergies) are particularly predisposed to UARS.
These ladies deny that they snore but admit they habitually sleep on their bellies, have recurrent neck pain on waking and will often describe themselves as ‘light sleepers’ as if it were a blessing!
UARS patients are seldom overweight but have craniofacial and upper airway characteristics that make breathing during sleep so effortful that it interrupts normal sleep architecture. The increased upper airway resistance in this situation does not lead to cessation of airflow (apnea) or a decrease in airflow with oxygen desaturation (hypopnea) as in OSA, but instead leads to an arousal (sleep disruption) secondary to the increased work of breathing.
Multiple arousals prevent these individuals from experiencing the beneficial restorative stages of sleep like NREM Stage 3 & 4 (i.e. deep slow-wave sleep when two-thirds of our ‘anti-aging’ growth hormone are secreted) and REM (rapid eye movement or dream sleep). As a consequence, the UARS patient usually complains of unrefreshing sleep, frequent awakenings, fatigue and cognitive impairment. They also tend to exhibit more sleep bruxism.
All young children who are mouth breathers and exhibit one or more of the following should be screened for UARS:
- restless sleep, sleep bruxism, snoring, or noisy breathing
- are academically challenged or have been previously diagnosed with attention deficit hyperactivity disorder (ADHD)
- show a failure to thrive (poor weight gain or weight loss)
- have enlarged tonsils and adenoids
- have a small or retruded lower jaw, or
- seeking the services of the orthodontist to treat their Class 2 malocclusions
Patients diagnosed with UARS are also more likely to suffer from comorbid generalised persistent pain disorders like fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, chronic temporomandibular joint disorders (TMJD), chronic fatigued syndrome, interstitial cystitis and vulvar vestibulitis.
Sleep bruxism is a common sleep-related movement disorder characterised by jaw clenching and/or tooth grinding. Although bruxism can also occur in REM and there’s some evidence that it can even trigger arousals, sleep bruxism is more commonly seen in stage 2 NREM (non-rapid eye movement) as the result rather than the cause of sleep arousals. Current research does not support the hypothesis and long-held dental dogma that occlusal interferences can initiate sleep bruxism. Note: It’s important that sleep bruxism be distinguished from parafunctional phenomena like awake bruxism (e.g. diurnal stress-related habitual jaw clenching/bracing).
Benefits of Treatment
OSA has been associated with serious long term health consequences such as hypertension, metabolic dysfunction, cardiovascular disease (including heart failure and stroke), erectile dysfunction, neurocognitive deficits and may cause serious alteration to one’s daytime vigilance, resulting in an increased risk of transport- or work-related accidents.
The symptoms of UARS patients although not as severe, include snoring, daytime fatigue, cognitive impairment, unrefreshing sleep, insomnia and frequent arousals from sleep. Treatment of UARS also has been shown to improve comorbid disorders like fibromyalgia, temporomandibular disorders, irritable bowel syndrome, chronic fatigue syndrome as well as chronic headaches.
Sleep bruxism can lead to severe tooth wear, cracked teeth, broken porcelain veneers and other dental restorations, tooth hypersensitivity/mobility, temporomandibular joint damage, jaw muscle pain, temporal headaches as well as poor quality sleep. It may also be one of the reasons why a majority of migraine sufferers awoke with or were awoken by headaches usually between 4.00am and 9.00am. (Fox AW, Davis RL. Headache1998; 38:436-441.)
At T32, the patient’s sleep disordered breathing (SDB) will be managed in close collaboration with a team of sleep professionals. Advances in ambulatory monitoring technology allow objective sleep studies (e.g. polysomnography or WatchPAT) to be performed in the convenience of your home.
Continuous positive airway pressure (CPAP) is generated from an automated bedside machine through a mask that covers the person's nose. The pressure of the air forces the person's airways to remain open during sleep.
Oral appliance therapy (OAT) consists primarily of custom-designed oral devices (e.g. mandibular advancement splints) similar to mouth guards, worn during sleep. These may advance or reposition the lower jaw, tongue, and soft palate, stabilize the lower jaw and hyoid bone, besides increasing the resting tone of the airway dilator muscles.
Although nasal CPAP is considered the gold standard, compliance is the real issue. Few women in romantic relationships would choose this treatment modality because it simply is NOT SEXY!
The American Academy of Sleep Medicine (AASM) now recommends OAT as the first line treatment for those with UARS, mild to moderate OSA, and for those patients with severe apnea who can’t tolerate or have failed CPAP. The efficacy of OAT is enhanced whenever the patient can breathe through his nose, has a low BMI or is willing to go on a weight loss programme.
Surgical procedures may include jaw advancement, or removal of excess throat tissue, tonsils, adenoids, the uvula, or parts of the soft palate. ‘Combination therapy’ is the buzz word today in the management of sleep disordered breathing!
- Why Oral Appliance Therapy (OAT) is ideally suited for women with sleep-related breathing disorders (SRBD)?
OAT (mandibular repositioning appliances) have been shown not to be inferior to CPAP in mild to moderate OSA but less effective in patients with severe OSA i.e. AHI>30(Hoekema et al: J Dent Res 2008; 87(9): 882-887). Premenopausal women who suffer from SRBD usually have UARS or mild OSA, unless they are obese. Most women in romantic relationships would reject CPAP simply because they don’t fancy looking or sounding like Darth Vader! OAT is also indicated for patients who are younger and leaner, and those who lead active outdoor lifestyles. You still wouldn’t be able to put a CPAP machine in your pocket and it needs a power source. We have helped many women who were previously so embarrassed by their ‘unfeminine’ snoring that without OAT they wouldn’t have been able to fulfil religious pilgrimages or pursue missionary work in foreign countries where they had to share sleeping quarters. OAT have also helped alleviate neck pains and eye bags as it allowed the ladies to sleep supine and not on their stomachs or face. As they say, restorative sleep takes years off your face!
- My only complaint is snoring. Why can’t I be fitted with an Oral Appliance Therapy without first going for a sleep test?
Your snoring might not be as benign as you think. If your Epworth sleepiness score is above 10 (you may take the ESS here) you should not proceed with OAT without a proper sleep test.
- My husband has severe OSA and is using a nasal CPAP machine but does not bring it along on his short trips. Can he use an Oral Appliance instead?
If he has severe sleep apnea, please let him know he is putting himself at risk of a stroke or heart attack, each time he goes without his CPAP. Many men have been referred to me for OAT as an alternative to CPAP especially after they find much younger girlfriends. To treat severe apneics with OAT is a serious challenge and my patients have to EARN their OAT. They first have to be compliant (i.e. >4hrs a night) with their CPAP usage for at least 6 months, be able to breathe effortlessly through their nose, and at the same time enrol in a weight loss program. The titration of the Oral Appliance has to be properly supervised and verified with sleep studies. Because the lower jaw has to be advanced much further than in those patients with UARS and mild to moderate OSA, there will be more likelihood of dento-occlusal changes. The dental sleep specialist will have to carefully assess whether the patient is a suitable candidate and will always work these cases in close collaboration with a sleep physician.
- Our 6-year old keeps us awake with his tooth grinding. Can anything be done to stop it?
There is mounting evidence that sleep bruxismmay serve as a “reactive or protective mechanism” against upper airway obstruction. Sleep bruxism in young children is almost invariably a manifestation of airway patency problems. Two paediatric studies have shown that sleep bruxism decreased after tonsillectomy or adenotonsillectomy from 45.5% to 11.8% and from 25.7% to 7.1% respectively. More importantly, you should take your child to a Paediatric ENT surgeon (preferably one who is also knowledgeable in sleep medicine) as soon as possible as this is the time when their young brains are developing and when proper sleep is vital. If your child also suffers from chronic nasal congestion and/or exhibits habitual mouth breathing, he will develop unfavourable cranio-cervical adaptations and dentofacial abnormalities. A visit to our orthodontist might be wise and early intervention (e.g. palatal expansion) discussed. If the bruxism is severe and causing teeth or temporomandibular joint damage, special occlusal splints can be considered although these may delay or interrupt normal tooth eruption. Other modalities like biofeedback devices (e.g. Grindcare) may be appropriate. Your dentist will discuss the pros and cons of each treatment with you.
- What is ‘combination therapy’?
The effectiveness of OAT is optimised only when the patient is able to breathe effortlessly through the nose. Thus OAT is frequently prescribed in conjunction with minimally invasive ENT surgical procedures like radiofrequency inferior turbinate reduction and/or the correction of a deviated nasal septum. Also, in the treatment of obese patients with severe OSA using CPAP, the high inspiratory pressures required to ‘air-splint’ or open the airway can be uncomfortably high and cause significant mask leaks. When the patient wears a properly titrated oral appliance in combination with CPAP therapy, lower inspiratory pressure settings may be employed. These are but a few examples of how we work in close collaboration with our team of sleep professionals.