Healing capacity of human and monkey dental pulps following experimentally‐induced pulpitis

Abstract

Abstract Intra‐ and extracellular products from oral bacteria were placed in Class V cavities prepared in dentin of human and monkey teeth to compare initial and late pulp tissue reactions. In one set of teeth, the bacterial material was left in the cavities for the entire experimental period (4, 10, 30 d in monkeys, 30 d in humans). In other teeth the challenge was stopped after 32 h and the bacterial material was removed and substituted with zinc‐oxide eugenol cement. The subsequent pulp tissue responses were observed histologically after 4, 10 (monkeys) and 30 d (humans and monkeys). Thirty‐two hours of bacterial challenge to human teeth induced intense acute inflammatory lesions. Four days of challenge in monkeys resulted in severe inflammatory cell involvement and pulpal necroses in a few teeth. At extended periods of observation severe inflammatory lesions were less frequent and the majority of the pulps showed tissue repair and healing at 30 d. This occurred irrespective of experimental protocol. Fourteen of 84 monkey teeth and none of 17 human teeth presented pulp tissue necrosis at follow‐up. Data showed that the‐dental pulp of both young human and monkey teeth can recuperate from a state of suppurative inflammatory involvement. Healing occurred irrespective of whether the bacterial challenge was removed or left in place. Findings also indicated that an acute inflammatory lesion rapidly could result in total pulp tissue necrosis.