Evaluation of the mono instrument (Wave One) mechanical action on the bacterial load reduction: In vitro study of 32 permanent human teeth.

Context: Enterococcus faecalis is the most common bacteria found in infected root canals.

Aim: The purpose of this study was to evaluate the effect of the mono instrument (wave-one® ) on the reduction of E. faecalis in root canals.

Materials and Methods: Thirty-two human monoroot teeth were used. After sterilization by autoclave, the teeth were infected by E. faecalis and incubated for 24 h. Each tooth underwent sampling before and after the root canal shaping. After serial dilution, samples were incubated, and colony-forming units were counted.

Results: The mono instrument technique reduced infection by E. faecalis in root canals of 30 teeth. The mean bacterial load (log10 ) was 3.98 before treatment and 1.20 after treatment. The paired t -test showed a significant mean difference (log10 ) of the bacterial load before and after treatment ( P < 0.0001).

Conclusion: This study found that the mono instrument (Wave One® ) significantly decreases bacterial load in root canals. However, the instrument alone is not enough to eradicate infections; thus, the use of a complementary antimicrobial is required.