[1] Univ Fed Rio de Janeiro, Inst Microbiol, BR-21941 Rio De Janeiro, Brazil
[2] Univ Fed Rio de Janeiro, Div Grad Periodont, Dept Dent Clin, BR-21941 Rio De Janeiro, Brazil
[3] Goldman Sch Med, Dept Oral Biol, Boston, MA USA
[4] Forsyth Inst, Dept Microbiol, Cambridge, MA USA
[5] Harvard Univ, Sch Dent Med, Boston, MA 02115 USA