When people are stressed they sometimes clench their jaw and grind their teeth.
This is called bruxism. Bruxism can happen day or night, with episodes sometimes lasting a few days, but other times going on for months.
Usually, it’s long-term teeth-grinding that can really cause problems.
Grinding the top and bottom teeth together can lead to something called dental abfraction.
This loss of tooth structure and general dental attrition occurs as the biting surfaces of each tooth are flattened out.
Over time, this can wear away the protective outer surface of the tooth, called the enamel, revealing the much more sensitive dentin below, leading to tooth hypersensitivity and increased risk of cavities.
In its most severe forms, bruxism can even cause teeth to fracture, loosen, or even fall out, and the constant grinding can also cause damage to existing dental work like crowns and fillings.
Occasionally people with bruxism bite their tongue as well, which can lead to a crenated or scalloped tongue marked by tooth-shaped indentations.
People with bruxism sometimes have canker sores from chewing their lips and inner cheeks, too.
Bruxism can also lead to temporomandibular joint disorder, or TMJ, which involves the temporalis, masseter, and pterygoid muscles; these muscles help with chewing by working together to move the mandible or jawbone.
Clenching these muscles over and over can be tiring and painful, particularly in the preauricular area right in front of the ear, causing headaches around the temples.