The cause of teeth grinding is related to psychological factors and may also be caused by TMJ pathology. Teeth grinding is an involuntary clenching or grinding of the upper and lower jaw when the teeth are not chewing. The main cause of teeth grinding is mental tension. It is mostly seen in clockworkers who are engaged in precision work, where the tension is not released during the day and is released at night in the form of grinding the teeth. Teeth grinding can also be a result of an uncoordinated bite, with individual bite highs caused by uneven wear of the teeth, which also adjust themselves by involuntary grinding of the teeth. Some teeth grinding is also related to lesions of the temporomandibular joint, where ankylosis or inflammation of the temporomandibular joint can cause involuntary grinding of the teeth. It is related to the usual large open mouth movements, such as swallowing half an apple in one gulp, which can trigger soreness in the temporomandibular area. Teeth grinding, if present for a long time, can lead to enamel abrasion and dentin exposure resulting in dentin hypersensitivity, in which case occlusal pads need to be made for wear to protect the teeth. The cause of teeth grinding is related to mental tension or bite misalignment and temporomandibular joint pathology. It is recommended to go to a regular medical institution for examination, clear diagnosis and symptomatic treatment.