A histobacteriologic study of dental and periapical structures after endodontic surgery

Abstract

Using a histobacteriologic technique in 66 biopsies containing apices and periapical structures, an attempt was made to determine the location of bacteria in the dental structures in cases followed-up after endodontic surgery. Furthermore, an attempt was made to evaluate the relation between bacteria found in the various structures and periapical tissue changes. The majority of bacteria were found in the dentin tubules. Usually these were located very near the canal. As no relation was found between the amount and location of the bacteria in the dentin tubules and the quantity of periapical inflammation, it was concluded that these bacteria were of minimal if any significance. This was also true in a case of root resection, where bacteria were present in the dentin tubules terminating in the cut root end. Contrary to these findings, bacteria were found more frequently in the root canal in cases with severe periapical inflammation, compared to cases with none, mild or moderate inflammation. Usually the cementum was found to contain no bacteria. Only in two cases, where the root ends for a long time had been surrounded by infected cysts, was the cementum found to be necrotic and invaded by bacteria. Except for three cases, no bacteria were found in the periapical soft tissues, even if these showed severe inflammation when examined histologically. Bacteria appeared to be more frequently encountered in dentin tubules in the group with periapical scar tissue compared to cases with no scar tissue.