title: An in vitro and ex vivo study on two antibiotic-based endodontic irrigants: a challenge to sodium hypochlorite.
abstract: Amongst the bacterial species which most often cause endodontic failures, Enterococcus faecalis is the most important. This study compared the effectiveness of sodium hypochlorite and two new generation antibiotic-based endodontic irrigants, Tetraclean and MTAD. By means of an in vitro agar dilution assay, we show that both Tetraclean and MTAD are 100% effective against 54 clinical isolates at dilutions up to 1:256 and 1:1048, respectively, whereas sodium hypochlorite completely loses its effectiveness when diluted more than 32 times. The bactericidal effect of both Tetraclean and MTAD can be ascribed not just to their antibiotic component per se, but also to a synergistic effect among the several ingredients included in the formulations. Moreover, by an ex vivo model of teeth extracted and experimentally infected with E. faecalis ATCC 29212, we show that both the antibiotic-based endodontic irrigants are effective in eliminating bacterial cells in 93 to 100% of the test samples. The results of these pre-clinical studies strongly support a wider use of this new group of endodontic irrigants in daily clinical practice.
authors.affiliation: Dipartimento di Scienze di Sanità Pubblica, Università di Modena e Reggio Emilia, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Ardizzoni
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Blasi
authors.forename: Cinzia
authors.initials: C
authors.lastname: Rimoldi
authors.forename: Luciano
authors.initials: L
authors.lastname: Giardino
authors.forename: Emanuele
authors.initials: E
authors.lastname: Ambu
authors.forename: Elena
authors.initials: E
authors.lastname: Righi
authors.forename: Rachele
authors.initials: R
authors.lastname: Neglia
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D019343:Citric Acid / Q000494:pharmacology*; D004202:Disinfectants / Q000494:pharmacology*; D004318:Doxycycline / Q000494:pharmacology*; D013293:Enterococcus faecalis / Q000187:drug effects*; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D011136:Polysorbates / Q000494:pharmacology*; D012388:Root Canal Irrigants / Q000737:chemistry / Q000494:pharmacology*; D012973:Sodium Hypochlorite / Q000494:pharmacology*; D014070:Tooth / Q000187:drug effects / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D004202:Disinfectants; C475043:MTAD (intracanal irrigant); D011136:Polysorbates; D012388:Root Canal Irrigants; D019343:Citric Acid; D012973:Sodium Hypochlorite; D004318:Doxycycline