title: Residual antibacterial activity of chlorhexidine digluconate and camphorated p-monochlorophenol in calcium hydroxide-based root canal dressings.
abstract: The purpose of this study was to evaluate the residual antibacterial activity of several calcium hydroxide [Ca(OH)2]-based pastes, placed in root canals of dogs' teeth with induced chronic periapical lesions. Root canals were instrumented with the ProFile rotary system and filled with 4 pastes: G1 (n=16): Ca(OH)2 paste + anesthetic solution; G2 (n=20): Calen paste + camphorated p-monochlorophenol (CMCP); G3 (n=18): Calen; and G4 (n=18): Ca(OH)2 paste + 2% chlorhexidine digluconate. After 21 days, the pastes were removed with size 60 K-files and placed on Petri plates with agar inoculated with Micrococcus luteus ATCC 9341. Pastes that were not placed into root canals served as control. After pre-diffusion, incubation and optimization, the inhibition zones of bacterial growth were measured and analyzed by Mann-Whitney U test at 5% significance level. All pastes showed residual antibacterial activity. The control samples had larger halos (p<0.05). The mean residual antibacterial activity halos in G1, G2, G3 and G4 were 7.6; 10.4; 17.7 and 21.4 mm, respectively. The zones of bacterial growth of G4 were significantly larger than those of G1 and G2 (p<0.05). In conclusion, regardless of the vehicle and antiseptic, all Ca(OH)2-based pastes showed different degrees of measurable residual antibacterial activity. Furthermore, unlike CMCP, chlorhexidine increased significantly the antibacterial activity of Ca(OH)2.
authors.affiliation: Department of Dentistry, Federal University of Vales do Jequitinhonha e Mucuri, Diamantina, MG, Brazil. janirsoares@cite11.com.br
authors.forename: Janir Alves
authors.initials: JA
authors.lastname: Soares
authors.forename: Mario Roberto
authors.initials: MR
authors.lastname: Leonardo
authors.forename: Mário
authors.initials: M
authors.lastname: Tanomaru Filho
authors.forename: Léa Assed Bezerra da
authors.initials: LA
authors.lastname: Silva
authors.forename: Izabel Yoko
authors.initials: IY
authors.lastname: Ito
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002126:Calcium Hydroxide / Q000737:chemistry / Q000494:pharmacology; D002164:Camphor / Q000494:pharmacology*; D002710:Chlorhexidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D002733:Chlorophenols / Q000494:pharmacology*; D004285:Dogs; D004338:Drug Combinations; D010483:Periapical Diseases / Q000188:drug therapy; D012387:Root Canal Filling Materials / Q000737:chemistry / Q000494:pharmacology; D012390:Root Canal Therapy / Q000379:methods
chemical_list: D000900:Anti-Bacterial Agents; D002733:Chlorophenols; D004338:Drug Combinations; D012387:Root Canal Filling Materials; D002164:Camphor; C029804:camphorated parachlorophenol; C010882:chlorhexidine gluconate; D002126:Calcium Hydroxide; D002710:Chlorhexidine