Evaluation of the antibacterial potential of tetracycline or erythromycin mixed with calcium hydroxide as intracanal dressing against Enterococcus faecalis in vivo.

Objective: We evaluated the intracanal antibacterial potential of tetracycline or erythromycin mixed with calcium hydroxide (CH) against enterococci in vivo.

Study Design: Fifty-five teeth in which enterococci were present were dressed for 1 month with either tetracycline (28 teeth) or erythromycin (27 teeth) mixed with CH.

Results: The tetracycline mixture was effective against enterococci in 22 teeth (79%). In 7 teeth, other microorganisms were recovered, resulting in a total antimicrobial effect of 54%. The corresponding results for erythromycin were 96% and 56%.

Conclusions: The antimicrobial treatment of CH in combination with either erythromycin or tetracycline had a significant effect on enterococci, but the overall antimicrobial effect was relatively weak. Erythromycin mixed with CH seems to be a valuable option in the battle against monoinfections of enterococci.