The occlusal table is the surface of a tooth that comes into contact with the opposite tooth. These are the grinding surfaces of the teeth that help break down food and the largest occlusal tables tend to be on the back teeth, or molars. The bicuspid teeth also have an occlusal table, and an occlusal load is the amount of force applied to the occlusal table by the jaw or external force. The jaw can exert a great deal of pressure per square inch, which is why teeth — specifically the enamel — is the strongest substance in the body. Injury can occur to the occlusal table, which is called occlusal trauma. The most common type of occlusal trauma is from bruxism, where the surfaces of the occlusal table become damaged and worn from excessive clenching and biting, usually during sleep. Occlusal trauma can also be caused by external forces, such as a blow to the head.