The physical or psychological condition produced by trauma. Periodontal traumatism describes the degenerative changes in the periodontium which occur when occlusal forces exceed physiological limits. If severe enough, it can result in thrombosis of blood vessels, haemorrhage, hyalinization of the periodontal fibres, and possibly necrosis of the periodontal fibres and bone in areas of excessive pressure. In areas where there is tension, the periodontal ligament is widened, bone and cementum resorption occurs and is sometimes additionally associated with tearing of the cementum or bone. Clinically, the teeth may show increased mobility and tenderness to percussion; there may also be pulpal hypersensitivity.