The primary goal of endodontic therapy is the reduction of microorganisms and their products from the root canal. Endodontic dental treatment is a procedure consisting of mechanical instrumentation, chemical treatment with flushing irrigation fluids, and root canal filling. Regardless of the instrumentation technique, manual or machine, a large part of the root canal remains uninstrumented due to its anatomical specificities such as accessory and lateral canals, istmus, enlargements. Therefore, flushing irrigation fluids with antimicrobial activity and ability to dissolve residual tissue should be used. There is no irrigant that combines all the ideal characteristics, and the combination of sodium hypochlorite and ethylene diaminoacetic acid is most commonly used. Irrigans work effectively when in direct contact with the root canal wall, which is especially important in the apical part of the root. The conventional rinsing method, syringe and needle, does not effectively remove the residual layer of the apical third of the root canal versus the ultrasonic activated rinsing fluid. During ultrasonic irrigation, energy is transferred from the oscillating instrument to the irrigant, increasing the degree of purity of the root canal by creating the phenomenons of acoustic microstreaming and cavitation. The literature reference compared the effectiveness of conventional and ultrasonic root canal rinsing.