title: Release and diffusion of hydroxyl ion from calcium hydroxide-based medicaments.
abstract: The release and diffusion of hydroxyl ions (OH(-)) of calcium hydroxide (Ca(OH)(2))-based intracanal medications may be affected by the association with other substances. The aim of this study was to evaluate the diffusion of OH- ions through root dentin by the medications: G1, Ca(OH)(2)/saline; G2, Calen; G3, Calen/camphorated p-monochlorophenol (CMCP); and G4, Calen/0.4% chlorhexidine (CHX). Root canals from bovine teeth were prepared in a standardized manner. A cavity until dentin was prepared in the middle third of the root surface of each specimen. The external surface of the root was made impermeable using a layer of adhesive, except the prepared cavity. The root canals were filled with different medications, and teeth were individually stored in flasks containing 10 ml distilled water at 37°C. The water pH was measured at 1, 3, 7, 14, 21, 30, and 60 days. Data obtained were subjected to anova and Tukey's tests. Increase in pH was observed at 3 days for Calen/CHX and from 7 to 14 days for the other mixtures. Calen paste promoted pH increase up to 21 days. Calen/CMCP had the highest pH up to 21 days, and all groups had similar results at 30 days. At 60 days, the greatest pH values were observed for Calen/CMCP and Calen alone. All different formulations of Ca(OH)(2)-based medications tested release hydroxyl ion that can diffuse through the dentin.
authors.affiliation: Department of Restorative Dentistry, Araraquara Dental School, UNESP-Univ Estadual Paulista, Araraquara, SP, Brazil.
authors.forename: Juliane Maria
authors.initials: JM
authors.lastname: Guerreiro-Tanomaru
authors.forename: Daniele Guidette
authors.initials: DG
authors.lastname: Chula
authors.forename: Regina Karla
authors.initials: RK
authors.lastname: de Pontes Lima
authors.forename: Fábio Luis Vilela Camargo
authors.initials: FL
authors.lastname: Berbert
authors.forename: Mário
authors.initials: M
authors.lastname: Tanomaru-Filho
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology* / Q000627:therapeutic use; D002126:Calcium Hydroxide / Q000494:pharmacology* / Q000627:therapeutic use; D002417:Cattle; D003804:Dentin / Q000187:drug effects*; D003806:Dentin Permeability / Q000187:drug effects*; D004058:Diffusion / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D006878:Hydroxides / Q000494:pharmacology*; D014677:Pharmaceutical Vehicles / Q000737:chemistry; D012388:Root Canal Irrigants / Q000494:pharmacology* / Q000627:therapeutic use; D014092:Tooth Root / Q000187:drug effects / Q000378:metabolism
chemical_list: D000890:Anti-Infective Agents; D006878:Hydroxides; D014677:Pharmaceutical Vehicles; D012388:Root Canal Irrigants; C031356:hydroxide ion; D002126:Calcium Hydroxide