Teeth grinding and clenching, medically known as bruxism, is an involuntary habit that occurs both when a person is awake (awake bruxism) and during sleep (sleep bruxism). Sleep bruxism is classified as a sleep-related movement disorder, and people often remain unaware they have the condition until symptoms manifest. This chronic force and friction can damage dental structures and surrounding tissues, leading to a variety of physical signs and symptoms.
Non-Dental Signs and Sounds
One of the most immediate indicators of bruxism is the sound it produces, especially at night. A sleeping partner may report hearing abrasive sounds like loud scraping, gnashing, or crunching noises as the teeth forcibly rub against one another.
Beyond sounds, a person may wake up with soreness or fatigue in the jaw muscles, which have been overworked during the night. The constant tension placed on the muscles of the head and neck can radiate, leading to discomfort elsewhere. A common symptom is a dull headache that starts around the temples, often present immediately upon waking.
The strain on the jaw joint and surrounding musculature can sometimes mimic an earache. This discomfort is caused by muscular tension in the temporomandibular joint (TMJ) area, not an actual ear infection.
Visual Evidence of Dental Damage
The most direct physical evidence of bruxism is visible damage to the teeth caused by the extreme forces involved. Prolonged grinding gradually wears down the chewing surfaces, resulting in noticeably flattened teeth. The pointed cusps of back teeth and the sharp edges of front teeth become smooth and worn, a condition known as attrition.
As the protective outer layer of enamel wears away, the underlying dentin may become exposed. Dentin is a softer, yellowish material, and its exposure can create areas of discoloration and increase tooth sensitivity to hot, cold, or sweet stimuli.
The forceful contact can also cause structural failures, resulting in small chips or fractures along the edges of teeth. In cases of severe clenching, a dentist may observe indentations or scalloping along the sides of the tongue or on the inside of the cheeks, created when soft tissue is pressed forcefully against the teeth.
Consequences for the Jaw and Facial Structure
The chronic pressure from bruxism extends beyond individual teeth to affect the entire temporomandibular joint (TMJ) complex. Excessive force can lead to dysfunction, often characterized by clicking, popping, or grating sounds when the mouth is opened or closed. In severe instances, the jaw may temporarily lock, making it difficult to fully open or close the mouth.
Continuous clenching forces the masseter muscles, located at the sides of the jaw, to work excessively. This overuse can lead to masseter muscle hypertrophy, causing the muscles to grow larger. This muscle enlargement can subtly alter the lower facial appearance, giving the jawline a more pronounced, angular, or square shape.
The sustained tension in the jaw muscles can also radiate down into the neck and shoulders, leading to stiffness and chronic muscle pain. Over time, significant wear on the teeth can reduce the overall vertical height of the face, pulling the chin and nose closer together.
Next Steps After Identifying Bruxism
Once a person recognizes the signs of bruxism, the most important step is to consult with a dental professional. A dentist or orthodontist will perform a clinical examination to confirm the diagnosis and assess the extent of the damage. This includes looking for wear patterns, checking for jaw muscle tenderness, and evaluating the function of the TMJ.
The dental professional may recommend a custom-fitted oral appliance, such as a night guard, to protect the teeth from further grinding and clenching forces. They may also discuss potential lifestyle modifications, such as stress management techniques, to help reduce the frequency of the habit.