Atividade antimicrobiana residual de pastas base de hidr¢xido de c lcio e associa‡ães como medica‡Æo intracanal / Residual antimicrobial activity of calcium hydroxide based pastes and associations as intracanal medication

A resistˆncia do biofilme endod“ntico pode requerer um per¡odo maior de permanˆncia da medica‡Æo intracanal a fim de prolongar sua a‡Æo antimicrobiana. O objetivo deste estudo foi avaliar a a‡Æo antimicrobiana residual das medica‡ães intracanal: G1) hidr¢xido de c lcio + soro; G2) Calen; G3) Calen + PMCC; G4) Calen + clorexidina 0,4% e G5) clorexidina gel 2% frente … Enterococcus faecalis, Candida albicans, Pseudomonas aeruginosa, Staphylococcus aureus e Kocuria rhizophila em 60 canais radiculares bovinos. Os canais radiculares foram instrumentados e preenchidos com as medica‡ães intracanal, as quais foram removidas ap¢s os per¡odos experimentais (15, 30, 60 e 90 dias) e empregadas na t‚cnica de difusÆo em  gar. Os halos de inibi‡Æo foram evidenciados por gel de TTC e entÆo mensurados. Os dados de halos de inibi‡Æo foram submetidos … an lise estat¡stica dos testes Kruskall-Wallis e Dunn, com n¡vel de significƒncia de 5%. O Ca(OH)2 + soro apresentou efeito at‚ o per¡odo de 15 dias. A pasta Calen demonstrou efeito residual aos 60 dias frente ao S. aureus, enquanto Calen/ PMCC at‚ o per¡odo de 90 dias frente …S. aureus eK. rhizophilae aos 30 dias paraE. faecalis. A pasta Calen associado … clorexidina foi efetiva frente … E. faecalis at‚ o per¡odo de 60 dias. A clorexidina gel 2% apresentou a‡Æo residual em todos os per¡odos, com exce‡Æo de E. faecalis aos 90 dias, tamb‚m apresentou atividade antimicrobiana mais prolongada, seguido das associa‡ães do hidr¢xido de c lcio com clorexidina e PMCC.

The endodontic biofilm resistance requires a longer period of intracanal medication to promote antimicrobial action. The aim of this study was to evaluate the residual antimicrobial activity of intracanal medications: G1) calcium hydroxide + saline; G2) Calen; G3) Calen+PMCC; G4) Calen + chlorhexidine 0.4% and G5) chlorhexidine gel 2% against Enterococcus faecalis, Candida albicans, Pseudomonas aeruginosa, Staphylococcus aureus, and Kocuria rhizophila. Root canals from 60 bovine teeth were instrumented and filled with intracanal medications. After the experimental periods (15, 30, 60 and 90 days), intracanal medications were removed and they were evaluated using the agar diffusion technique. The inhibition zones were detected by TTC gel and then measured. Data from inhibition zones were analyzed statistically by Kruskal-Wallis and Dunn test, with a significance level of 5%. The Ca(OH) 2 + saline showed residual effect limited to a period of 15 days. The Calen had residual effects at 60 days against S. aureus, while Calen + PMCC were observed until 90 days against S. aureus, K. rhizophila, and 30 days for E. faecalis. The Calen paste associated to chlorhexidine was effective against E. faecalis up to 60 days. The gel chlorhexidine 2% had residual action in all periods, except for E. faecalis for 90 days, and it has more prolonged antimicrobial activity, followed by the associations of calcium hydroxide with chlorhexidine and PMCC.