Influence on periapical tissues of indigenous oral bacteria and necrotic pulp tissue in monkeys

Abstract

Abstract – In nine monkeys (Macaca Fascicularis) the pulps of 78 teeth were aseptically necrotized. Twenty‐six of the pulp chambers were kept bacteria‐free by sealing, while 52 were infected by the indigenous oral flora. The results were recorded clinically, radiographically and microbiologically at the begining of the experiment and after 6–7 months. Tje final examination also included histologic recordings. The initiallyt noninfected root canals were all sterile at the final samplings, indicating that the risk of contamination (including hemarogenous) of root canals of this animal is very slight. It was show that noninfected necrotic pulp tissue did not induce inflammatory reactions in the apical tissues. By contrast, teeth with infected pulp tissu showed inflammatory reactions clinically (12/52 teeth) and radiographically (47/52 teeth). Facultatively anaerobic streptococci, coliform rods and obligately anacrobic bacterial strains were most frequently found. In the final samples the number of obligately anaerohic strains increased. Some microogramisms which were isolated in the initial samples were not detected in the final samples. All infected teeth histologically examined showed strong inflammatory reactions in the periapical region.