@article{souza junior_silva_brito_lucena_morais_2021,  title={Association between Pell and Gregory classification and the difficulty of the extraction of the lower third parties},  volume={69},  ISSN={1981-8637},  url={https://doi.org/10.1590/1981-86372021002120190101},  DOI={10.1590/1981-86372021002120190101},  journal={RGO - Revista Gaúcha de Odontologia},  publisher={Faculdade São Leopoldo Mandic},  author={SOUZA JUNIOR, Erasmo Freitas de and SILVA, Janielma Azevedo and BRITO, José Iago Pereira de and LUCENA, Eudes Euler de Souza and MORAIS, Hecio Henrique Araújo de},  year={2021},  pages={e20210021} }