Do Periodontopathogens Disappear After Full-mouth Tooth Extraction?

Aim: To monitor the intra-oral microbiological changes after full-mouth extraction using quantitative polymerase chain reaction (qPCR).

Material And Methods: Nine patients with severe, aggressive periodontitis, for whom a full-mouth tooth extraction was the only remaining treatment option were recruited. Before and 6 months after extraction, microbial samples were obtained (tongue, saliva and subgingival plaque) and analysed by qPCR.

Results: The elimination of subgingival niches, by extraction of all natural teeth, resulted in a 3-log reduction of Porphyromonas gingivalis and Tannerella forsythia, and more modest reductions of Aggregatibacter actinomycetemcomitans and Prevotella intermedia. However, the detection frequencies of these periodontopathogens in saliva and on the tongue remained unchanged after full-mouth tooth extraction.

Conclusion: In contrast to what has been believed so far, full-mouth tooth extraction does not result in eradication of all periodontopathogens but only in a significant reduction. The clinical consequences of this observation remain speculative.