@article{chagas_almeida_lisboa_ferreira_mattos_mucha_2018,  title={Duration of effectiveness of Botulinum toxin type A in excessive gingival display: a systematic review and meta-analysis},  volume={32},  ISSN={1806-8324},  url={https://doi.org/10.1590/1807-3107bor-2018.vol32.0030},  DOI={10.1590/1807-3107bor-2018.vol32.0030},  journal={Brazilian Oral Research},  publisher={Sociedade Brasileira de Pesquisa Odontológica - SBPqO},  author={Chagas, Taísa Figueiredo and Almeida, Natalia Valli de and Lisboa, Cinthia Oliveira and Ferreira, Daniele Masterson Tavares Pereira and Mattos, Claudia Trindade and Mucha, José Nelson},  year={2018},  pages={e30} }