Evaluation of the microbiota of primary endodontic infections using checkerboard DNA-DNA hybridization.
OBJECTIVE
The aim of this study was to evaluate the composition of the microbiota of primary endodontic infections in 111 selected cases of single-rooted teeth with necrotic pulp.


METHODS
Samples were collected from the root canals using #15 Hedströen-type files and two sterile paper points, which were introduced 1 mm short of the apical foramen. The presence, levels, and proportions of 40 different bacterial species in each sample were determined using DNA probes and checkerboard DNA-DNA hybridization techniques.


RESULTS
The mean number of species per sample was 22. Enterococcus faecalis (89.3%), Campylobacter gracilis (89.3%), Leptotrichia buccalis (89.3%), Neisseria mucosa (87.5%), Prevotella melaninogenica (86.6%), Fusobacterium nucleatum ssp. vincentii (85.7%), Eubacterium saburreum (75.9%), Streptococcus anginosus (75%), and Veillonella parvula (74.1%) were the most prevalent species. The species found in highest mean counts (over 10(5)) were F. nucleatum ssp. vincentii (13.14 x 10(5)), E. saburreum (5.67 x 10(5)), E. faecalis (5.38 x 10(5)), N. mucosa (4.19 x 10(5)), V. parvula (3.63 x 10(5)), C. gracilis (3.46 x 10(5)), Treponema socranskii (3.34 x 10(5)), Porphyromonas endodontalis (2.96 x 10(5)), Porphyromonas gingivalis (2.85 x 10(5)), Micromonas micros (2.81 x 10(5)), Prevotella nigrescens (2.68 x 10(5)) and Fusobacterium nucleatum ssp. nucleatum (2.64 x 10(5)). Most of these species were also found in high proportions.


CONCLUSIONS
Our results suggest that several bacterial species considered to be oral pathogens seem to be implicated in the etiology of primary endodontic infections.
Sassone
L
L
Proclin Department, Rio de Janeiro State University, RJ, Brazil. lsassone@uerj.br
Fidel
R
R
Figueiredo
L
L
Fidel
S
S
Faveri
M
M
Feres
M
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D002167:Campylobacter / Q000145:classification; D015169:Colony Count, Microbial; D015342:DNA Probes; D004269:DNA, Bacterial / Q000032:analysis*; D003786:Dental Pulp Cavity / Q000382:microbiology; D003790:Dental Pulp Necrosis / Q000382:microbiology*; D013293:Enterococcus faecalis / Q000145:classification; D005051:Eubacterium / Q000145:classification; D005260:Female; D016967:Fusobacterium nucleatum / Q000145:classification; D016905:Gram-Negative Bacterial Infections / Q000175:diagnosis*; D016908:Gram-Positive Bacterial Infections / Q000175:diagnosis*; D006801:Humans; D045183:Leptotrichia / Q000145:classification; D008297:Male; D008875:Middle Aged; D042807:Neisseria mucosa / Q000145:classification; D009693:Nucleic Acid Hybridization / Q000379:methods*; D010462:Peptostreptococcus / Q000145:classification; D045202:Porphyromonas endodontalis / Q000145:classification; D016966:Porphyromonas gingivalis / Q000145:classification; D001443:Prevotella melaninogenica / Q000145:classification; D045242:Prevotella nigrescens / Q000145:classification; D034366:Streptococcus anginosus / Q000145:classification; D014208:Treponema / Q000145:classification; D014678:Veillonella / Q000145:classification
D015342:DNA Probes; D004269:DNA, Bacterial