A MICROBIOLOGICAL AND IMMUNOLOGICAL STUDY OF ENDODONTIC-PERIODONTIC LESIONS

The microflora and humoral immune response in tissue from the periodon tal pockets and root canals of five teeth with endodontic-periodontic lesions were examined. We found more microbes in the periodontal pocke ts than in the root canals. The flora in the periodontal pockets were dominated by rods and motile organisms, whereas that in the root canal s was largely rods and cocci. We detected no spirochetes in the root c anals. The cultivable microflora in the periodontal pockets comprised a high number of different species of bacteria, whereas those in the r oot canals included only a small number of species. There was no corre lation between microbial isolates and antibody titer in the apical tis sues or periodontal pockets. We conclude from these studies that the m icroflora of infected root canals are simple and limited, and that the local humoral immune response does not seem to affect the pathogenesi s of disease directly.