@article{singh_uppoor_nayak_2012,  title={A comparative evaluation of the efficacy of manual, magnetostrictive and piezoelectric ultrasonic instruments: an in vitro profilometric and SEM study},  volume={20},  ISSN={1678-7757},  url={https://doi.org/10.1590/S1678-77572012000100005},  DOI={10.1590/S1678-77572012000100005},  number={1},  journal={Journal of Applied Oral Science},  publisher={Faculdade De Odontologia De Bauru - USP},  author={Singh, Sumita and Uppoor, Ashita and Nayak, Dilip},  year={2012},  month={Jan},  pages={21–26} }