Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), cloning,
and sequencing were applied to the microbiologic study of acute periapical abscesses
of endodontic origin in children to examine the predominant bacteria.
Purulent material was collected from 11 children diagnosed with acute abscesses of
endodontic origin, and DNA was extracted to evaluate the predominant bacteria by using
PCR-DGGE, cloning, and sequence analysis.
Bacterial DNA was present in all of the 11 purulence samples. The microflora of clinical
purulence samples were profiled by the PCR-DGGE method, and overall 17 bacterial genera
were identified. The number of bacterial phylotypes in the purulence samples ranged
from 1-8 (mean, 5.5). The most dominant genera found were Prevotella (24%), Fusobacterium
(17.7%), Porphyromonas (13.9%), Lactobacillus (11.3%), Peptostreptococcus (8.3%),
Streptococcus (6.4%), Eubacterium (3.8%), Campylobacter (3.3%), Treponema (2.6%),
and Bulleidia (2.6%).
The DGGE allowed visualization of the bacterial qualitative composition and revealed
the major bacteria in the samples. The dominant bacteria associated with acute periapical
abscess examined by PCR-DGGE, cloning, and sequencing methods are similar to those
of culture-dependent studies. Although PCR-DGGE, cloning, and sequencing methods detected
some bacteria at lower proportions than are unreported by culture methods, the method
has the disadvantage of low resolution and is too time-consuming and laborious and
more expensive.
Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All
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