title: Does the Reciproc file remove root canal bacteria and endotoxins as effectively as multifile rotary systems?
abstract: OBJECTIVE
  To evaluate the effectiveness of Reciproc for the removal of cultivable bacteria and endotoxins from root canals in comparison with multifile rotary systems.
  
  
  METHODS
  The root canals of forty human single-rooted mandibular pre-molars were contaminated with an Escherichia coli suspension for 21 days and randomly assigned to four groups according to the instrumentation system: GI - Reciproc (VDW); GII - Mtwo (VDW); GIII - ProTaper Universal (Dentsply Maillefer); and GIV -FKG Race(™) (FKG Dentaire) (n = 10 per group). Bacterial and endotoxin samples were taken with a sterile/apyrogenic paper point before (s1) and after instrumentation (s2). Culture techniques determined the colony-forming units (CFU) and the Limulus Amebocyte Lysate assay was used for endotoxin quantification. Results were submitted to paired t-test and anova.
  
  
  RESULTS
  At s1, bacteria and endotoxins were recovered in 100% of the root canals investigated (40/40). After instrumentation, all systems were associated with a highly significant reduction of the bacterial load and endotoxin levels, respectively: GI - Reciproc (99.34% and 91.69%); GII - Mtwo (99.86% and 83.11%); GIII - ProTaper (99.93% and 78.56%) and GIV - FKG Race(™) (99.99% and 82.52%) (P < 0.001). No statistical difference were found amongst the instrumentation systems regarding bacteria and endotoxin removal (P > 0.01).
  
  
  CONCLUSIONS
  The reciprocating single file, Reciproc, was as effective as the multifile rotary systems for the removal of bacteria and endotoxins from root canals.
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School - State University of Campinas- UNICAMP, Piracicaba, SP, Brazil.
authors: A C S
authors: AC
authors: Marinho
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School - State University of Campinas- UNICAMP, Piracicaba, SP, Brazil.
authors: F C
authors: FC
authors: Martinho
authors: Postgraduate Program in Dentistry, Ceuma University-UniCEUMA, São Luis, MA, Brazil.
authors: L M
authors: LM
authors: Gonçalves
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School - State University of Campinas- UNICAMP, Piracicaba, SP, Brazil.
authors: H R C
authors: HR
authors: Rabang
authors: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School - State University of Campinas- UNICAMP, Piracicaba, SP, Brazil.
authors: B P F A
authors: BP
authors: Gomes
mesh_terms: D058491:Bacterial Load; D001641:Bicuspid; D003666:Decontamination / Q000295:instrumentation*; D003762:Dental Instruments; D003786:Dental Pulp Cavity / Q000382:microbiology*; D004731:Endotoxins; D004866:Equipment Contamination; D004926:Escherichia coli; D006801:Humans; D066298:In Vitro Techniques; D018915:Root Canal Preparation / Q000295:instrumentation*
chemical_list: D004731:Endotoxins
keywords: bacterial reduction; disinfection; endodontic treatment; endotoxins; reciprocating motion; rotary instruments