In addition to the biological and immunological factors, the followings can be effective in causing pain: Chemical mediators, changes in local adaptation of periapical tissue, changes in cyclic nucleotides, immunological phenomena and psychosomatic factors .
There is a possibility that the injuries caused in periapical tissue during endodontic treatment of teeth with vital pulp leads to stimulating of greater secretion of inflammatory mediators such as prostaglandins, leukotrienes, serotonin, histamine, and bradykinin .
There is no evidence of adverse histological reaction at the periapical tissue
Chow, The periapical tissue
reaction to a calcium phosphate cement in the teeth of monkeys, J.
It should also adhere to the preparation walls and seal the root canal system, be non-toxic, well-tolerated by periapical tissues
and promote healing (Gartner & Dorn, 1992)
Without treatment, this eventually results in infection of the dental pulp and surrounding periapical tissues
Endodontics deals with the morphology, physiology, pathology, etiology, diagnosis, prevention and treatment of diseases of the pulpal and periapical tissues
In some cases, the inflammation and infection of the pulp may extend beyond the tooth to the periapical tissues
of the periodontal ligament.
Slow leakage of irritants into the periapical tissues
causes an injury which is not manifested in the short term.