Polymerase chain reaction-based denaturing gradient gel electrophoresis in the evaluation of oral microbiota.
OBJECTIVE
Clinical evaluation of oral microbial reduction after a standard prophylactic treatment has traditionally been based on bacterial cultivation methods. However, not all microbes in saliva or dental plaque can be cultivated. Polymerase chain reaction-based denaturing gradient gel electrophoresis (PCR-DGGE) is a cultivation-independent molecular fingerprinting technique that allows the assessment of the predominant bacterial species present in the oral cavity. This study sought to evaluate the oral microbial changes that occurred after a standard prophylactic treatment with a conventional oral care product using PCR-DGGE.


METHODS
Twelve healthy adults participated in the study. Pooled plaque samples were collected at baseline, 24 h after prophylaxis (T1), and 4 days after toothbrushing with fluoride toothpaste (T4). The total microbial genomic DNA of the plaque was isolated. PCR was performed with a set of universal bacterial 16S rDNA primers. The PCR-amplified 16S rDNA fragments were separated by DGGE. The effects of the treatment and of dental brushing were assessed by comparing the PCR-DGGE fingerprinting profiles.


RESULTS
The mean numbers of detected PCR amplicons were 22.3 +/- 6.1 for the baseline group, 13.0 +/- 3.1 for the T1 group, and 13.5 +/- 4.3 for the T4 group; the differences among the three groups were statistically significant (P < 0.01). The study also found a significant difference in the mean similarities of microbial profiles between the baseline and the treatment groups (P < 0.001).


CONCLUSIONS
PCR-based DGGE has been shown to be an excellent means of rapidly and accurately assessing oral microbial changes in this clinical study.
Li
Y
Y
Department of Basic Science and Craniofacial Biology, College of Dentistry, New York University, New York, NY 10010, USA. yihong.li@nyu.edu
Saxena
D
D
Barnes
V M
VM
Trivedi
H M
HM
Ge
Y
Y
Xu
T
T
D000328:Adult; D000704:Analysis of Variance; D015373:Bacterial Typing Techniques; D016172:DNA Fingerprinting / Q000379:methods*; D004269:DNA, Bacterial / Q000032:analysis; D003773:Dental Plaque / Q000382:microbiology*; D003777:Dental Prophylaxis; D003802:Dentifrices / Q000737:chemistry; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D005459:Fluorides; D006801:Humans; D008297:Male; D009691:Nucleic Acid Denaturation; D016133:Polymerase Chain Reaction; D012463:Saliva / Q000382:microbiology*; D016037:Single-Blind Method; D014099:Toothbrushing
D004269:DNA, Bacterial; D003802:Dentifrices; D005459:Fluorides