Bruxism is the involuntary gnashing, grinding, or clenching of teeth. It is usually an unconscious activity, whether the individual is awake or asleep; often associated with fatigue, anxiety, emotional stress, or fear and frequently triggered by occlusal irregularities. This usually results in abnormal wear patterns on the teeth, periodontal breakdown, and joint or neuromuscular problems.7
Patients may use clenching and grinding interchangeably, as if they are the same behaviour, since their actions can cause similar results. While many people audibly grind and silently clench, they are different actions. Clenching is defined as clamping the teeth together firmly and tightening the jaw muscles.2 Clenching causes less obvious wear to the teeth but still results in substantial muscular soreness, pain and damage to the temporomandibular joint (TMJ) and periodontium. The terms grinding and bruxism are used interchangeably and involve repetitive movement of the TMJ with the teeth held together and/or by bracing or thrusting the mandible.2 Grinding visibly shows wear and flattening of the teeth along with substantial muscular soreness, pain and damage to the TMJ and periodontium.