Valdez, RMA. Detection of Gram-negative periodontopathogenic microorganisms and quantification of endotoxin in orthodontic metallic brackets, with or without use of an antimicrobial agent-An in vivo study. [dissertação]. Ribeirão Preto: FORP-Universidade de São Paulo; 2009. Using the biomolecular technique Checkerboard DNA-DNA Hybridization and the Limulus Amebocyte Lysate (LAL) assay, the purposes of the present randomized