“…A combined mechanical and systemic antibiotic therapy has, in numerous studies, proved to be more successful than mechanical therapy alone (Slots et al 1986, Goodson 1994, Van Winkelhoff et al 1996, Berglundh et al 1998, Tinoco et al 1998, Winkel et al 1998, Flemmig et al 1998). But even though these studies have shown the effectiveness of an adjunct antibiotic therapy, it was impossible to eliminate all the putative periodontal pathogens such as A. actinomycetemcomitans , P. gingivalis and P. intermedia out of the periodontal pockets respectively out of the oral cavity in every patient (Slots & Rosling 1983, Loesche et al 1984, Gusberti et al 1988, Pedrazzoli et al 1992, Hitzig et al 1997, Winkel at al. 1998, Tinoco et al 1998, Flemmig et al 1998, Wong et al 1999, Feres et al 1999, Riep et al 1999, Buchmann et al 2000).…”