Combinations of bacterial species in endodontic infections.
OBJECTIVE
This study was undertaken to investigate combinations of bacteria found in root-canal infections of teeth with periapical bone destruction without clinical signs and symptoms.


METHODS
Endodontic samples from 58 root canals were cultured anaerobically and microorganisms were counted and identified. Eighty-one combinations of microorganisms were found and tested for a symbiotic relationship using the Fisher's exact test and Odds ratio calculation.


RESULTS
All samples contained microorganisms with a median CFU mL(-1) of 8x10(4) per sample. Strict anaerobic species accounted for 87% of the microflora. The most prevalent bacteria were Prevotella intermedia, Peptostreptococcus micros and Actinomyces odontolyticus, present in 33, 29 and 19%, respectively, of the cultured canals. A significant relationship (P<0.05) and an Odds ratio >2 were found between P. intermedia and P. micros, P. intermedia and P. oralis, A. odontolyticus and P. micros, Bifidobacterium spp. and Veillonella spp.


CONCLUSIONS
These results indicate that endodontic pathogens do not occur at random but are found in specific combinations.
Department of Cariology Endodontology Pedodontology, Academic Center for Dentistry Amsterdam, the Netherlands. l.peters@acta.nl
L B
LB
Peters
P R
PR
Wesselink
A J
AJ
van Winkelhoff
D016301:Alveolar Bone Loss / Q000382:microbiology*; D001421:Bacteria, Anaerobic / Q000302:isolation & purification; D001424:Bacterial Infections / Q000382:microbiology*; D016009:Chi-Square Distribution; D015169:Colony Count, Microbial; D003788:Dental Pulp Diseases / Q000382:microbiology*; D017753:Ecosystem; D006801:Humans; D016017:Odds Ratio; D010485:Periapical Periodontitis / Q000382:microbiology*; D018709:Statistics, Nonparametric