title: Clinical efficacy of EDTA ultrasonic activation in the reduction of endotoxins and cultivable bacteria.
abstract: OBJECTIVE
  This clinical study was conducted to investigate the influence of 17% ethylenediaminetetraacetic acid (EDTA) ultrasonic activation after chemomechanical preparation (CMP) on eliminating/reducing oral bacterial lipopolysaccharides (known as endotoxins) and cultivable bacteria in teeth with pulp necrosis and apical periodontitis.
  
  
  METHODS
  Samples were taken from 24 root canals at several clinical periods: S1 - before CMP; S2 - after CMP; S3 - after EDTA: G1 - with ultrasonic activation (n = 12) and G2 - without ultrasonic activation (n = 12). Root canals were instrumented using Mtwo rotary files. Culture techniques were used to determine the number of colony-forming units (CFU). Limulus amebocyte lysate (LAL) was used to measure endotoxin levels. Friedman's and Wilcoxon signed-rank tests were used to compare the amount of bacteria and endotoxin levels in each period (P < 0.05).
  
  
  RESULTS
  Endotoxins and cultivable bacteria were recovered in 100% of the initial samples (S1). CMP was effective in reducing endotoxins and bacterial load (all with P < 0.05). Higher values of endotoxin reduction were achieved with EDTA ultrasonic activation [G1, 0.02 EU mL-1(range 0.01-0.75)] compared with the no activation group [G2, 1.13 EU mL-1(range 0.01-8.34)] (P < 0.05). Regarding bacterial reduction, no statistically significant difference was found in S3, regardless of the group (G1, G2, P > 0.05).
  
  
  CONCLUSIONS
  Chemomechanical preparation was effective in reducing bacteria and endotoxins, but could not completely eliminate them. The ultrasonic activation of EDTA was effective in further reducing endotoxin levels in the root canals of teeth with pulp necrosis and apical periodontitis.
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, SP, Brazil.
authors: D R
authors: DR
authors: Herrera
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, SP, Brazil.|Department of Restorative Dentistry, Endodontic Division, São Jose dos Campos Dental School, State University of São Paulo, UNESP, Sao Jose dos Campos, SP, Brazil.
authors: F C
authors: FC
authors: Martinho
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, SP, Brazil.
authors: A
authors: A
authors: de-Jesus-Soares
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, SP, Brazil.
authors: A A
authors: AA
authors: Zaia
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, SP, Brazil.
authors: C C R
authors: CCR
authors: Ferraz
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, SP, Brazil.
authors: J F A
authors: JFA
authors: Almeida
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, SP, Brazil.
authors: B P F A
authors: BPFA
authors: Gomes
mesh_terms: D001419:Bacteria / Q000187:drug effects / Q000528:radiation effects; D003790:Dental Pulp Necrosis / Q000628:therapy*; D004492:Edetic Acid / Q000627:therapeutic use*; D004731:Endotoxins / Q000037:antagonists & inhibitors*; D006801:Humans; D010485:Periapical Periodontitis / Q000628:therapy*; D018915:Root Canal Preparation / Q000379:methods*; D013234:Stem Cells / Q000187:drug effects / Q000528:radiation effects; D014465:Ultrasonics
chemical_list: D004731:Endotoxins; D004492:Edetic Acid
keywords: 
  EDTA
  ; endotoxin; root canal infection; ultrasonic