Evaluation of Microbial Reduction in Root Canals Instrumented with Reciprocating and Rotary Systems

Svrha: Ovim istraživanjem in vitro željela se procijeniti učinkovitost dezinfekcije korijenskih kanala nakon instrumentacije sistemom ReciprocTM i ProTaper UniversalTM, uz irigaciju 1-postotnim natrijevim hipokloritom (NaOCl). Materijali i metode: Četrdeset kanala jednokorijenskih mandibularnih premolara inficirano je bakterijama Enterococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus i Candida albicans, a dvadeset kanala ostavljeno je bez infekcije. Uzorci su nasumično podijeljeni u šest grupa (n = 10): grupa 1: ProTaper UniversalTM + 1-postotni NaOCl; grupa 2 (pozitivna kontrola): ProTaper UniversalTM + fiziološka otopina; grupa 3 (negativna kontrola bez mikroorganizama): ProTaper UniversalTM + fiziološka otopina; grupa 4: ReciprocTM + 1-postotni NaOCl; grupa 5 (pozitivna kontrola): ReciprocTM + fiziološka otopina; grupa 6 (negativna kontrola bez mikroorganizama): ReciprocTM + fiziološka otopina. Rezultati: Kombinacija sistema ProTaper UniversalTM i 1-postotnog natrijeva hipoklorita potpuno je eliminirala sve mikroorganizme. Rast mikroorganizama uočen je pri korištenju sistema ReciprocTM i 1-postotnog natrijeva hipoklorita. Zaključak: Protokoli provedeni u ovom istraživanju pokazali su da sistem ReciprocTM uz 1-postotni NaOCl nije uspio u cijelosti eliminirati iz korijenskih kanala E. faecalis, P. aeruginosa, S. aureus i C. albicans.Objective: This in vitro study aimed to evaluate the efficacy of the disinfection of root canal systems carried out with ReciprocTM and ProTaper UniversalTM systems using 1% sodium hypochlorite (NaOCl). Methods: Forty human single-rooted mandibular premolars were infected with Enterococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans, and twenty were not infected. The specimens were randomly divided into 6 groups (n = 10): Group 1: ProTaper UniversalTM + 1% NaOCl; Group 2 (positive control): ProTaper UniversalTM + saline; Group 3 (negative control without microorganisms): ProTaper UniversalTM + saline; Group 4: ReciprocTM + 1% NaOCl; Group 5 (positive control): ReciprocTM + saline; Group 6 (negative control without microorganisms): ReciprocTM + saline. Samples were collected before and after the completion of specific treatments, and plated in specific media cultures. The Fisher exact test was used for the statistical analysis of differences in terms of presence or absence of microbial growth among groups. For all tested pathogens, significant differences (p < 0.001) were verified between the instrumentation systems used. Results: ProTaper UniversalTM associated with 1% NaOCl completely eliminated all microorganisms. Microbial growth, however, was observed when ReciprocTM was used associated with 1% NaOCl. Conclusion: According to the protocol executed for this study, the ReciprocTM system associated with 1% NaOCl was not able to completely eliminate E. faecalis, P. aeruginosa, S. aureus and C. albicans from the root canal systems