Comparison of debris extruded apically and working time used by ProTaper Universal rotary and ProTaper retreatment system during gutta-percha removal . J Appl Oral Sci [Internet]. 2010 Dec. 1 [cited 2024 Jun. 2];18(6):542-5. Available from: https://www.revistas.usp.br/jaos/article/view/3842