Comparison of restriction enzyme analysis and amplified fragment length polymorphism typing of Porphyromonas gingivalis isolated from spouses.

INTRODUCTION: In the past, theories on the transmission of Porphyromonas gingivalis between individuals have been based on, among other techniques, restriction enzyme analysis (REA) of bacterial DNA. Currently, amplified fragment length polymorphism (AFLP) may be a more sophisticated alternative. The possibility of automatic pattern analysis and digital storage of the typing data enables the comparison of patterns from a large number of strains in a broad time frame. The aim of this study was to compare REA profiles with AFLP patterns of P. gingivalis strains isolated from periodontitis patients and their spouses. METHODS: Forty-two P. gingivalis strains were isolated from different sites in the mouth from six adult patients with periodontitis and their spouses. DNA of the bacterial isolates was subjected to REA and AFLP analysis. RESULTS: One single type of P. gingivalis was found in each individual with both methods, regardless of the site of isolation. Indistinguishable types were found in four of the six couples with both techniques. Different types were found in two couples with both the REA and the AFLP method. CONCLUSIONS: The AFLP typing technique confirms earlier observations on the transmission of P. gingivalis between spouses. This new technique can replace REA typing.

[Dissertations 25 years after date 12. Classification and virulence of black-pigmented bacteria in relation to periodontitis]. / Proefschriften 25 jaar na dato 12. Classificatie en virulentie van zwart-gepigmenteerde bacteriën in relatie tot parodontitis.

Bacteria in dental plaque play an essential role in the origin and development of periodontitis. In the seventies of the last century it became clear that black-pigmented bacteria of the genus Bacteroides play a vital role in this process. These bacteria are currently known as Porphyromonas gingivalis and Prevotella intermedia. In a PhD dissertation 25 years ago it was shown by DNA analysis that this group of bacteria is very heterogeneous, and that different species exist, which are associated with different oral infections. Because Porphyromonas gingivalis plays an important role in periodontitis, this bacterium has been investigated extensively during the last decades. The entire genome is now known at the DNA level. In addition, transmission between spouses has been shown to be possible, although it does not always cause periodontal disease. It is not yet possible to conclude if for patients with Porphyromonas gingivalis a different antibiotic policy should be used compared to patients without this bacterium.