Clinical investigation of the efficacy of chemomechanical preparation with rotary nickel-titanium files for removal of endotoxin from primarily infected root canals.
BACKGROUND
This clinical study was conducted to investigate the ability of chemomechanical preparation with 2.5% NaOCl + 17% ethylenediaminetetraacetic acid (EDTA) and rotary nickel-titanium (NiTi) system in removing endotoxin from primary root canal infection with apical periodontitis.


METHODS
Twenty-one root canals with necrotic pulps were selected. Samples were collected before (s1) and after chemomechanical preparation (s2). The limulus amebocyte lysate (LAL) assay was used to quantify endotoxins.


RESULTS
The LAL assay indicated that endotoxins were present in 100% of the root canals investigated (19/19) before (s1) and after chemomechanical preparation (s2). Analyses of the quantitative data revealed that the endotoxin content was significantly reduced at s2 (98.06%) compared with that at s1 (P < .05).


CONCLUSIONS
Our findings indicate that chemomechanical preparation with 2.5% NaOCl + 17% EDTA and rotary NiTi files was effective in reducing endotoxin load in the root canal infection from primarily infected teeth with apical periodontitis.
Department of Restorative Dentistry, Endodontic Division, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brasil.
Frederico C
FC
Martinho
Wanderson M M
WM
Chiesa
Ariane C S
AC
Marinho
Alexandre A
AA
Zaia
Caio C R
CC
Ferraz
José F A
JF
Almeida
Francisco J
FJ
Souza-Filho
Brenda P F A
BP
Gomes
D000293:Adolescent; D000328:Adult; D000368:Aged; D002614:Chelating Agents / Q000627:therapeutic use; D003722:Dental Alloys / Q000737:chemistry*; D003786:Dental Pulp Cavity / Q000187:drug effects / Q000382:microbiology*; D003790:Dental Pulp Necrosis / Q000382:microbiology / Q000628:therapy; D004492:Edetic Acid / Q000627:therapeutic use; D004731:Endotoxins / Q000032:analysis / Q000037:antagonists & inhibitors*; D004867:Equipment Design; D006801:Humans; D008033:Limulus Test; D008070:Lipopolysaccharides / Q000032:analysis / Q000037:antagonists & inhibitors; D008875:Middle Aged; D009532:Nickel / Q000737:chemistry*; D010485:Periapical Periodontitis / Q000382:microbiology / Q000628:therapy; D012388:Root Canal Irrigants / Q000627:therapeutic use; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods*; D012973:Sodium Hypochlorite / Q000627:therapeutic use; D014025:Titanium / Q000737:chemistry*; D055815:Young Adult
D002614:Chelating Agents; D003722:Dental Alloys; D004731:Endotoxins; D008070:Lipopolysaccharides; D012388:Root Canal Irrigants; C040654:titanium nickelide; D009532:Nickel; D004492:Edetic Acid; D014025:Titanium; D012973:Sodium Hypochlorite