DentalCare Logo

Bruxism: The Grind of the Matter

Course Number: 485

Common Causes of Bruxism

Stress, lifestyle habits, medications, medical conditions and occlusion are major contributors to grinding.


Stress is defined as a physical, chemical or emotional factor that causes bodily or mental tension and may be a factor in disease causation. Bruxism may be related to a person’s state of mind. Our bodies react to stress whether it is wanted or not.2 In a medical or biological context stress is a physical, mental or emotional factor that causes bodily or mental tension.14 Stress can be caused by external environmental sources, psychological or social situations. Internal sources such as illness or a medical procedure can also cause stress. Stress can initiate the “fight or flight” response, a complex reaction of neurologic and endocrinologic systems.8

Stress is simply a reaction to a stimulus that disturbs our physical or mental equilibrium creating unresolved emotions such as frustration, anger, competitiveness, aggressiveness, anxiety, tension, hyperactive personality or unresolved conflict. Suppression of feelings can also cause undue stress. The psychological factor is related to depression, anxiety and emotional stress, which plays an important role in starting and perpetuating bruxism as well as its frequency and severity. It is also believed depressed, anxious and emotionally stressed individuals present a greater predisposition for developing sleep bruxism as a response to releasing daily emotional stress.15 Since bruxism can be considered an emotional response, people who tend to suppress their feelings of frustration and anger and who tend to have aggressive, competitive, hurried personalities, and built up nervous tension are at an increased risk of grinding their teeth. Type A, Obsessive-Compulsive Disorder, and hyperactive personalities also lead to bruxism. Stressful periods such as examinations, family bereavement, divorce or marriage, relocating, overworking, excessive worrying or any other situation that can add extra pressure can intensify bruxism.16,17

Lifestyle Habits

Many lifestyle choices can increase the cycle of bruxism, especially with the use of psychoactive substances such as alcohol, tobacco, drugs and caffeine.18


Drinking alcohol excessively doubles a patient’s chance of developing sleep bruxism. Bruxing tends to intensify after alcohol consumption. The occasional drink such as a glass of wine or two before going to bed to help one sleep better sounds good–but in reality, alcohol is known to break up sleeping patterns. If your patient sleeps poorly, this triggers their muscles to hyperactivate and the teeth to grind. It also increases the amount of arousal sleep.18

The mechanisms of action of alcohol on the central nervous system include alterations of the levels of:

  • glutamate (neurotransmitters that send signals in the brain and throughout the nerves in the body),

  • dopamine (the reward and pleasure center),

  • serotonin (neurotransmitters that relay messages from one brain area to another, affecting mood, sleep, appetite, memory and learning, temperature regulation and social behavior),

  • extrapyramidal regions (help regulate and modulate motion).

When these alterations are affected, it decreases the modulating role the glutamate neurons play on the dopaminergic system in the central nervous system. This action generates important alterations in behavior and motor activity, which in turn increases bruxism.4

Tobacco Use

Tobacco is a stimulant and affects the dopaminergic system. Bruxism in tobacco users is twice as prevalent as in non-users with sleep bruxism episodes five times more frequent per night. Bruxism related symptoms are three times higher in tobacco users than non-users. Users also notice and report bruxing more than non-users.4

Recreational Drugs

Stimulants in recreational drugs such as ecstasy, cocaine, methamphetamine (meth) and heroine increase bruxism. These drugs are central nervous system stimulants. Their mechanism of action is based on the neuronal transmitters in the brain with the dopaminergic system being the most involved. Neuronal transmitters are essential for functions in the central nervous system that involve learning, memory, sleep cycle, body movement, hormone regulation and many more.19 They also initiate motor disorders causing bruxism. Ecstasy generates the most concern in relation to severe awake and sleep bruxism. It can last in the system for 6-8 hours, with bruxism as a side effect in one-third of users. With regular use these drugs can promote bruxism leading to severe attrition in a short amount of time.4


Drinking caffeinated drinks, such as soda, high energy drinks, tea and coffee (six or more cups a day) increases the risks of bruxing. Caffeine has a half-life of six hours after it has been consumed. Caffeine is a stimulant that can promote muscle activity and cause frequent waking periods at night.20,21,22