Bruxism

Bruxism (from the Greek βρυγμός (brugmós), "gnashing of teeth") is characterized by the grinding of the teeth and is typically accompanied by the clenching of the jaw. It is an oral parafunctional activity that occurs in most humans at some time in their lives. In most people, bruxism is mild enough not to be a health problem. While bruxism may be a diurnal or nocturnal activity, it is bruxism during sleep that causes the majority of health issues and can even occur during short naps. Bruxism is one of the most common sleep disorders.

Causes

Numerous articles have incorrectly cited bruxism as being a reflex chewing activity, but bruxism is more accurately classified as a habit. Reflex activities happen reliably in response to a stimulus, without involvement of subconscious brain activity, and bruxism does not. All habitual activities are triggered by one kind of stimulus or another, and that does not make the habit a reflex. Chewing is a complex neuromuscular activity that is controlled by subconscious processes, with higher control by the brain. During sleep, the subconscious processes become active, while the higher control is inactive, resulting in bruxism. Some bruxism activity is rhythmic (like chewing), and some is sustained (clenching). Researchers classify bruxism as "a habitual behavior, and a sleep disorder."

The etiology of problematic bruxism is unknown, though several conditions are known to be linked to bruxism. It is theorized that certain medical conditions can trigger bruxism, including digestive ailments and anxiety.

Signs

The effects of bruxism on an anterior tooth, revealing the dentin and pulp which are normally hidden by enamelMost bruxers are not aware of their bruxism, and only 5% go on to develop symptoms, such as jaw pain and headaches, which will require treatment. In many cases, a sleeping partner or parent will notice the bruxism before the person experiencing the problem becomes aware of it.

Bruxism can result in abnormal wear patterns of the occlusal surface, abfractions and fractures in the teeth. This type of damage is categorised as a sign of occlusal trauma.

Over time, dental damage will usually occur. Bruxism is the leading cause of occlusal trauma and a significant cause of tooth loss and gum recession.

In a typical case, the canines and incisors of the opposing arches are moved against each other laterally, i.e., with a side-to-side action, by the medial pterygoid muscles that lie medial to the temporomandibular joints bilaterally. This movement abrades tooth structure and can lead to the wearing down of the incisal edges of the teeth. People with bruxism may also grind their posterior teeth, which will wear down the cusps of the occlusal surface. Bruxism can be loud enough to wake a sleeping partner. Some individuals will clench the jaw without significant lateral movements. Teeth hollowed by previous decay (caries), or dental drilling, may collapse, as the cyclic pressure exerted by bruxism is extremely taxing on the tooth structure.

Symptoms

Patients may present with a variety of symptoms, including:

• Morning migraines or headaches
• Pain (jaw, TMJ, sinus, facial muscle and nerve, neck, shoulder,back, and/or others)
• Earache
• Tinnitus (ringing in the ear)
• Vertigo
• Stress or tension
• Depression
• Eating disorders
• Waking exhausted
• Poor sleep
• Insomnia
• Daytime sleepiness
• Eye irritation
• Head tingling