An analysis in vivo of intracanal bacterial load before and after chemo-mechanical preparation: a comparative analysis of two irrigants and two activation techniques
Background: The goals of this randomized double-blind trial were to assess the antimicrobial activity
in vivo
of Sodium hypochlorite (NaOCl) vs. chlorhexidine gluconate (CHX) used in combination either with EndoActivator®
or IRRI S® files in patients with apical periodontitis.
Material and Methods: A total of 120 patients with apical periodontitis (in single or multiple root canals) were
randomly assigned to the four irrigation protocols outlined below: Group A: 5.25% sodium hypochlorite (NaOCl)
+ EndoActivator®; Group B: 5.25% NaOCl + IRRI S® files; Group C: 2% chlorhexidine gluconate (CHX) +
EndoActivator®; Group D: 2% CHX + IRRI S® files. Paper points were used to collect microbiological samples
before (1A samples) and after (1B samples) irrigation. Viable colony-forming units (CFU) were quantified twice:
(1) without speciation, and (2) only for
Enterococcus Faecalis
(
EF
). Statistical analysis was performed using SPSS
22.0 for Windows.
Results: No significant differences were observed between NaOCl and CHX in the reduction of CFU; in fact, reduction was > 93% for the two irrigants. Conversely, statistically significant differences were found between the two
activation techniques (sonic and ultrasonic) in the reduction of
Enterococcus faecalis
(
EF
). Thus, the effectiveness
of ultrasonic activation was significantly higher (> 93%; p=0.012) as compared to sonic activation. Following the
combination of the two irrigants with the two activation techniques (groups A, B, C and D), significant differences
were observed between group A and B (
p
=0.025) in the reduction of
EF
populations, reaching up to 94%.
Conclusions: NaClO and CHX are effective in reducing intracanal bacterial load. Ultrasonic activation is the most
effective activation technique in reducing
EF
populations
