title: Use of nanoparticulate zinc oxide as intracanal medication in endodontics: pH and antimicrobial activity.
abstract: The aim of this study was to evaluate the pH and antimicrobial activity of micro or nanoparticulate zinc oxide (ZnO) pastes with or without calcium hydroxide (CH). The following medications were evaluated: microparticulate ZnO + polyethylene glycol (PEG) 400; nanoparticulate ZnO + PEG 400; PEG 400; CH + microparticulate ZnO + PEG 400 and CH + nanoparticulate ZnO + PEG 400. The pH was assessed between 12 hours and 28 days, using a digital pH meter. The antimicrobial activity against Enterococcus faecalis (ATCC-9212), Candida albicans (ATCC-10231), Pseudomonas aeruginosa (ATCC-27853), Staphylococcus aureus (ATCC-6538) and Kocuria rhizophila (ATCC-9341) was determined in triplicate using agar diffusion test. The results were submitted to Kruskal-Wallis/Dunn and ANOVA/Tukey tests with 5% significance. The highest pH values were found for CH+ZnO, with higher values for nanoparticulate ZnO after 12 hours and 21 days (p < 0.05). CH+ZnO medication promoted higher growth inhibition against P. aeruginosa and lower against E. faecalis. Calcium hydroxide pastes have higher pH and antimicrobial activity when associated with either micro- or nanoparticulate zinc oxide.
authors.forename: Juliane M
authors.initials: JM
authors.lastname: Guerreiro-Tanomaru
authors.forename: Kamila Figueiredo
authors.initials: KF
authors.lastname: Pereira
authors.forename: Camila Almeida
authors.initials: CA
authors.lastname: Nascimento
authors.forename: Maria Inês Basso
authors.initials: MI
authors.lastname: Bernardi
authors.forename: Mario
authors.initials: M
authors.lastname: Tanomaru-Filho
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D002126:Calcium Hydroxide / Q000494:pharmacology; D002176:Candida albicans / Q000187:drug effects; D004337:Drug Carriers; D004338:Drug Combinations; D004357:Drug Synergism; D013293:Enterococcus faecalis / Q000187:drug effects; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D008835:Micrococcaceae / Q000187:drug effects; D053758:Nanoparticles / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D012388:Root Canal Irrigants / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects; D013997:Time Factors; D015034:Zinc Oxide / Q000494:pharmacology*
chemical_list: D000890:Anti-Infective Agents; D004337:Drug Carriers; D004338:Drug Combinations; D012388:Root Canal Irrigants; D011092:Polyethylene Glycols; D002126:Calcium Hydroxide; D015034:Zinc Oxide