Methods of detection of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Tannerella forsythensis in periodontal microbiology, with special emphasis on advanced molecular techniques: a review.
BACKGROUND
Certain specific bacterial species from the subgingival biofilm have demonstrated aetiological relevance in the initiation and progression of periodontitis. Among all the bacteria studied, three have shown the highest association with destructive periodontal diseases: Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg) and Tannerella forsythensis (Tf). Therefore, the relevance of having accurate microbiological diagnostic techniques for their identification and quantification is clearly justified.


OBJECTIVE
To evaluate critically all scientific information on the currently available microbial diagnostic techniques aimed for the identification and quantification of Aa, Pg and Tf.


CONCLUSIONS
Bacterial culturing has been the reference diagnostic technique for many years and, in fact, most of our current knowledge on periodontal microbiology derives from cultural data. However, the advent of new microbial diagnostics, mostly based on immune and molecular technologies, has not only highlighted some of the shortcomings of cultural techniques but has also allowed their introduction as easy and available adjunct diagnostic tools to be used in clinical research and practice. These technologies, mostly polymerase chain reaction (PCR), represent a field of continuous development; however, we still lack the ideal diagnostic to study the subgingival microflora. Qualitative PCR is still hampered by the limited information provided. Quantitative PCR is still in development; however, the promising early results reported are still hampered by the high cost and the equipment necessary for the processing.


CONCLUSIONS
Quantitative PCR technology may have a major role in the near future as an adjunctive diagnostic tool in both epidemiological and clinical studies in periodontology. However, culture techniques still hold some inherent capabilities, which makes this diagnostic tool the current reference standard in periodontal microbiology.
Sanz
Mariano
M
Laboratory of Microbiology, University Complutense, 28040 Madrid, Spain. marianosanz@odon.ucm.es
Lau
Laura
L
Herrera
David
D
Morillo
Juan Manuel
JM
Silva
Augusto
A
D016976:Aggregatibacter actinomycetemcomitans / Q000302:isolation & purification*; D001431:Bacteriological Techniques / Q000379:methods*; D001439:Bacteroides / Q000302:isolation & purification*; D002478:Cells, Cultured / Q000382:microbiology; D015342:DNA Probes / Q000302:isolation & purification; D006801:Humans; D007118:Immunoassay / Q000379:methods; D025202:Molecular Diagnostic Techniques / Q000379:methods; D015341:Nucleic Acid Probes / Q000302:isolation & purification; D010518:Periodontitis / Q000175:diagnosis / Q000382:microbiology*; D016133:Polymerase Chain Reaction / Q000379:methods; D016966:Porphyromonas gingivalis / Q000302:isolation & purification*
D015342:DNA Probes; D015341:Nucleic Acid Probes