Efficacy of double antibiotics in hydroxypropyl methylcellulose for bactericidal activity against Enterococcus faecalis and Streptococcus gordonii in biofilm.

Objective: This study aimed to investigate the efficacy of double antibiotics, including ciprofloxacin and metronidazole, in a new vehicle, hydroxypropyl methylcellulose (HPMC), against Enterococcus faecalis and Streptococcus gordonii grown in biofilm.

Design: Human mandibular premolars were prepared and divided into four groups: (i) negative control, (ii) positive control, (iii) infected with E. faecalis and S.