Resumo

CAMARA, Andréa Cruz; ALBUQUERQUE, Miracy Muniz de; AGUIAR, Carlos Menezes  e  CORREIA, Ana Cristina Regis de Barros. Antimicrobial activity of chlorhexidine in root canals instrumented with the ProTaper Universal^TM System. Braz. J. Oral Sci. [online]. 2010, vol.9, n.3, pp. 402-409. ISSN 1677-3225.

AIM: The purpose of the present study was to evaluate the antimicrobial activity of 0.2%, 1%, and 2% chlorhexidine in root canals instrumented with the ProTaper Universal^TM system. METHODS: Fifty human mandibular premolar teeth were infected with a mixture of Candida albicans, Pseudomonas aeruginosa, Enterococcus faecalis and Staphylococcus aureus. The specimens were randomly divided into 5 groups with 10 root canals according to the irrigant used. All root canals were instrumented with the ProTaper Universal^TM system. Assessment of the antimicrobial action of the irrigant was performed before, during, and after instrumentation. Data were analyzed statistically by Chi-squared test and the Fisher exact test at 5% significance level. RESULTS: The 0.2% chlorhexidine solution was ineffective against all test microorganisms. The 1% chlorhexidine solution was effective in eliminating P. aeruginosa and C. albicans after the use of the F1 and F3 instruments, respectively. The 2% chlorhexidine solution was effective at killing S. aureus, P. aeruginosa and C. albicans after the use of the S1 instrument. There were statistically significant differences (p<0.05) between the concentrations of chlorhexidine and the instruments used. CONCLUSIONS: The 0.2% chlorhexidine solution in combination with rotary instrumentation was ineffective against all test microorganisms. The 1% chlorhexidine solution was ineffective against S. aureus and E. faecalis. The 2% chlorhexidine solution was not sufficient to inactivate E. faecalis.

Palavras-chave : antimicrobial activity; chlorhexidine; ProTaper Universal^TM; root canal irrigant; rotary instrumentation.