Effect of ethylenediaminetetraacetic acid and sodium hypochlorite irrigation on Enterococcus faecalis biofilm colonization in young and old human root canal dentin: in vitro study.
BACKGROUND
The alterations in dentin tissue depending on increasing age might cause different adhesion capability of bacteria, yielding differences in clinical approaches regarding root canal irrigation. This study, therefore, aimed to evaluate the effects of ethylenediaminetetraacetic acid (EDTA) and sodium hypochlorite (NaOCl) on Enterococcus faecalis biofilm growth in root canal dentin of young and old individuals.


METHODS
The root canals of extracted young (<30 years) and old (>60 years) single-rooted human teeth were sectioned at the crown and the apical parts. The root canals of the mid-root sections were enlarged with #2 Gates-Glidden burs. After treatment with 17% EDTA + 2.5% NaOCl, 17% EDTA alone, 2.5% NaOCl alone, or saline, the samples were incubated in E. faecalis suspension for 24 hours. Thereafter, root canal samples were enlarged again with #3 Gates-Glidden burs, and the removed dentin chips were collected. Bacteria were dispersed by using sonication, serially diluted, and then plated for counting on agar plates as colony-forming units. Scanning electron microscopy and confocal laser scanning microscopy investigations were also carried out to examine the biofilm formation on the dentin. Data were analyzed with Kruskal-Wallis test and Mann-Whitney U test with Bonferroni adjustment.


RESULTS
Combination of EDTA and NaOCl significantly reduced the amount of intracanal biofilm in both age groups (P < .01). However, the bacterial counts of E. faecalis in the old group were still higher (P < .05).


CONCLUSIONS
It might be suggested that root canals from elderly population are more susceptible to canal infection. However, combined application of EDTA and NaOCl significantly reduces the amount of intracanal biofilm.
Ozdemir
Hüseyin Ozgur
HO
Department of Endodontics, Faculty of Dentistry, Hacettepe University, Ankara, Turkey.
Buzoglu
Hatice Dogan
HD
Calt
Semra
S
Stabholz
Adam
A
Steinberg
Doron
D
D000328:Adult; D000367:Age Factors; D001422:Bacterial Adhesion / Q000187:drug effects; D018441:Biofilms / Q000187:drug effects*; D015169:Colony Count, Microbial; D003786:Dental Pulp Cavity / Q000382:microbiology*; D003804:Dentin / Q000382:microbiology*; D004492:Edetic Acid / Q000494:pharmacology; D013293:Enterococcus faecalis / Q000187:drug effects*; D006801:Humans; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D012388:Root Canal Irrigants / Q000494:pharmacology*; D012973:Sodium Hypochlorite / Q000494:pharmacology
D012388:Root Canal Irrigants; D004492:Edetic Acid; D012973:Sodium Hypochlorite