 Microbiological examination Immediately before and 142 days after surgery subgingival plaque samples are taken from the test sites of and analyzed by a commercially available real-time PCR test Meridol Paro Diagnostik, GABA GmbH, Lörrach, Germany for Aggregatibacter actinomycetemcomitans A.a., Porphyromonas gingivalis P.g., Tannerella forsythia T.f., Treponema denticola T.d., Fusobacterium nucleatum F.n., and Prevotella intermedia P.i.. The detection limit of this test is 102. 