[1] When the jaws close, for instance during chewing or at rest, the relationship between the opposing teeth is referred to as occlusion.

[5] Clinically, there is a number of physiological results that serve as evidence of occlusal trauma:,[6][7] Microscopically, there will be a number of features that accompany occlusal trauma:[8] It was concluded that widening of the periodontal ligament was a "functional adaptation to changes in functional requirements".

Excesses of:[10] Duration Frequency Magnitude, and Direction (off axis loading) Primary occlusal trauma will occur when there is an adequate periodontal attachment apparatus.

In primary occlusal trauma, the cause of the mobility was the excessive force being applied to a tooth with an adequate attachment apparatus.

As with primary occlusal trauma, treatment may include either a removable prosthesis or implant-supported crown or bridge.