SNORING AND SLEEP APNEA
In September 1995 the American Sleep Disorder Association (ASDA) endorsed oral appliance therapy as the third currently acceptable treatment modality for snoring and sleep apnea. The two most common solutions include continuous positive air pressure or the removal of either the excess palatal tissue or the uvula.
It has been estimated that 60% of men and 40% of women between the ages of 40 and 60 years of age snore. Snoring occurs when there is a partial obstruction of the airway which causes the palatal tissues to vibrate. Obstructive sleep apnea occurs when the airway is completely blocked for certain periods of time. As many as 20 million people in North America may have sleep apnea. Snoring is a social problem, particularly for the spouse, but obstructive sleep apnea poses a significant health risk for the patient in that it can lead to irregular heartbeat, high blood pressure, heart attacks and strokes.
SLEEP APNEA
Sleep apnea is a type of breathing disorder which is a serious, potentially life-threatening condition characterized by brief interruptions of breathing during sleep. There are basically three types of apnea:
1. Central Apnea
The upper airway is open, but no oxygen is getting into the system. This occurs because the patient is not getting a chemical response from the brain to stimulate the lungs and the diaphragm to assist with breathing.
2 . Obstructive Sleep Apnea
The lungs and the diaphragm are functioning normally, but no oxygen is entering the system because there is an obstruction in the upper airway.
3. Mixed Apnea
This is a combination of central and obstructive sleep apnea.
Oral appliances are only indicated for use in patients suffering from obstructive sleep apnea (OSA). The signs and symptoms of OSA include snoring, excessive daytime sleepiness, gasping or choking during the night, non-refreshed sleep, fragmented sleep, clouded memory, irritability, personality changes, decreased sex drive, impotence, and morning headaches.
Factors that affect obstructive sleep apnea are as follows:
- Age
- Obesity
- Alcohol
- Sedative Hypnotics (sleeping pills)
Children can also snore and suffer from obstructive sleep apnea. Often they are highly allergic and their airway is blocked due to enlarged adenoids, tonsils or swollen nasal mucosa. Clinical signs would indicate a turned up nose, allergic shiners under the eyes, mucous draining out of the nose, mouth breathing, and a nasal sound to the voice. Other signs are bed wetting, irritability, difficulty in concentrating at school and hyperactivity
At the present time, obstructive sleep apnea is defined as a medical problem and the diagnosis must be made by a medical doctor or sleep physician (pulmonologist) who is specially trained in the area of sleep medicine.
The dental profession has an important role to play in the treatment of patients with snoring and sleep apnea. If 60% of men and 40% of women between forty and sixty years of age snore, this is a huge problem. Snoring is a serious social problem for the spouse, but obstructive sleep apnea can be a life threatening situation for the patient in that it can lead to irregular heartbeat, high blood pressure and strokes.
At the present time, obstructive sleep apnea is a medical condition that is being controlled and treated mainly by the medical profession. Despite the fact that in September 1995, the American Sleep Disorder Association finally endorsed oral appliance therapy as the third currently acceptable treatment method for snoring and sleep apnea, the vast majority of the medical doctors are not aware of the value of oral appliances
As time goes on, the public is going to become more aware of the health risks associated with snoring and sleep apnea. It is the dental professionals responsibility to educate their members, the public and the medical profession about the important role that dentists and oral appliances play in the treatment of snoring and obstructive sleep apnea.
SLEEP ARCHITECTURE
This describes the stages and cycles of sleep. There are two main categories of sleep:
1. Non-Rapid Eye Movement (NREM)
2. Rapid Eye Movement (REM)
Non Rapid Eye Movement (NREM)
- Transitional Phase - Between wakefulness and sleep. This lasts for one to seven minutes and is 5% of the total sleep time.
- Light Sleep Phase - This is 50% of the total sleep time.
- Slow Wave Phase (Delta Phase) - A deeper and more relaxed sleep associated with 20% of the total sleep time.
Rapid Eye Movement (REM)
This is a period of deep, refreshing sleep. Eyes move side to side and the skeletal muscles are nearly paralyzed which results in a loss of muscle tone in the upper airway. This represents 25% of the total sleep time and is the stage where dreaming occurs.
Excessive Daytime Sleepiness (EDS)
People who suffer from obstructive sleep apnea have a fragmented sleep architecture which causes them to spend an excessive amount of time in the lighter stages of sleep at the expense of the Delta Phase and REM stage. This causes them to have excessive daytime sleepiness due to their lack of sleep at night.
Apnea and Hypopnea
Apnea is defined as a period of cessation of breathing during sleep for ten seconds or longer. If the patient has more than five episodes of apnea per hour of sleep, this is considered clinically significant and helps confirm the diagnosis of obstructive sleep apnea. Hypopnea occurs when the decrease in airflow results in a 4% decrease in oxyhemoglobin concentration in the blood.