title: LPS levels in root canals after the use of ozone gas and high frequency electrical pulses.
abstract: The present study aims to verify the effect of ozone gas (OZY® System) and high frequency electric pulse (Endox® System) systems on human root canals previously contaminated with Escherichia colilipopolysaccharide (LPS). Fifty single-rooted teeth had their dental crowns removed and root lengths standardized to 16 mm. The root canals were prepared up to #60 hand K-files and sterilized using gamma radiation with cobalt 60. The specimens were divided into the following five groups (n = 10) based on the disinfection protocol used: OZY® System, one 120-second-pulse (OZY 1p); OZY® System, four 24-second-pulses (OZY 4p); and Endox® System (ENDOX). Contaminated and non-contaminated canals were exposed only to apyrogenic water and used as positive (C+) and negative (C-) controls, respectively. LPS (O55:B55) was administered in all root canals except those belonging to group C-. After performing disinfection, LPS samples were collected from the canals using apyrogenic paper tips. Limulus Amoebocyte Lysate (LAL) was used to quantify the LPS levels, and the data obtained was analyzed using one-way ANOVA. The disinfection protocols used were unable to reduce the LPS levels significantly (p = 0.019). The use of ozone gas and high frequency electric pulses was not effective in eliminating LPS from the root canals.
authors.affiliation: Clinical Department, School of Dentistry, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: Tiago André Fontoura de
authors.initials: TA
authors.lastname: Melo
authors.affiliation: Clinical Department, School of Dentistry, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: Grasiela Sabrina Longhi
authors.initials: GS
authors.lastname: Gründling
authors.affiliation: School of Dentistry, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: Francisco
authors.initials: F
authors.lastname: Montagner
authors.affiliation: Gramado, Gramado, RS, Brazil.
authors.forename: Alcione Luiz
authors.initials: AL
authors.lastname: Scur
authors.affiliation: Institute of Clinical Education, Warwick Medical School, University of Warwick, Coventry, United Kingdom.
authors.forename: Liviu
authors.initials: L
authors.lastname: Steier
authors.affiliation: Clinical Department, School of Dentistry, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: Roberta Kochenborger
authors.initials: RK
authors.lastname: Scarparo
authors.affiliation: Clinical Department, School of Dentistry, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: José Antônio Poli de
authors.initials: JA
authors.lastname: Figueiredo
authors.affiliation: Clinical Department, School of Dentistry, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: Fabiana Vieira
authors.initials: FV
authors.lastname: Vier-Pelisser
mesh_terms: D000704:Analysis of Variance; D003786:Dental Pulp Cavity / Q000382:microbiology*; D004564:Electrocoagulation / Q000379:methods*; D004731:Endotoxins / Q000032:analysis*; D004926:Escherichia coli; D006801:Humans; D008033:Limulus Test; D008070:Lipopolysaccharides / Q000032:analysis*; D010083:Oxidants, Photochemical; D010126:Ozone; D011897:Random Allocation; D015203:Reproducibility of Results; D018915:Root Canal Preparation / Q000379:methods; D013997:Time Factors
chemical_list: D004731:Endotoxins; D008070:Lipopolysaccharides; D010083:Oxidants, Photochemical; D010126:Ozone; C044101:endotoxin, Escherichia coli