Biologic effects of endodontic procedures on developing incisor teeth: II. Effect of pulp injury and oral contamination

Abstract

A series of pulp injuries was induced on fourteen developing incisor teeth of four young primates. Following this injury the pulp canals of the teeth were allowed to remain open and exposed to the oral environment for a period of 7 to 95 days. Microscopic examination of the teeth and periodontal tissues revealed a progression in the intensity and severity of the periapical inflammation during the early stages of the observation period. Later stages displayed irregular and limited attempts at continued root formation and apical closure by dental hard tissue and bone. The genesis of this tissue was apparently related to residual odontogenic cells of the pulp and to the growth of cells into the pulp space from the periapical tissues. Continued root growth and foraminal closure was often seen despite the presence of pronounced inflammatory changes in both the residual pulp and the periapical tissues.