Occlusion means the contacting and meeting of teeth of the upper and lower arches. The association and correlation between the mandibular and maxillary teeth is called the occlusion. Occlusion can be when biting or chewing something, or when the teeth are at rest in normal conditions when the mouth is closed.

In ideal conditions, the upper teeth and the lower teeth should meet perfectly. There should not be any gap or misalignment between these teeth. Any misalignment or irregularity is called malocclusion. Malocclusion leads to various dental and general health problems.

When the teeth come into contact with each other during rest, when the mouth is closed or while sleeping or being awake, it is called a static occlusion. When the teeth come in contact with each other while functioning, like chewing and biting, it is called dynamic occlusion.

Maximum intercuspation is a condition when the cusps of the teeth of the upper and lower arches interpose and merge with each other. An occlusal design when the frontal teeth protect the latter teeth is called a mutually protected occlusion. The damage caused due to malocclusion is called occlusal trauma. Occlusal trauma includes pain, loose teeth, tooth migration, fremitus, etc.

An occlusal split is a removable device which is used for the treatment of malocclusion and other similar dental problems, for instance, Bruxism. This appliance fits onto the upper and lower tooth arch and ends the malocclusion.