Introduction

One of the primary objectives of root canal therapy is the removal of microbial species within the canal system. Such goal is accomplished by cleansing, disinfecting and shaping of the canals through mechanical instrumentation, irrigation and the use of intracanal medicaments.

Purpose

To compare the effectiveness in inhibiting the growth of Fusobacterium nucleatum of 3 intracanal medicaments: chlorhexidine (CHX), calcium hydroxide (Ca(OH)2) and iodine potassium iodide (IKI) used individually and in various combinations.

Methods

F. nucleatum subspecies nucleatum was grown on agar plates. Paper filter disks were immersed in each medicament and placed on the agar surface. Plates were incubated in an anaerobic chamber for 7 days. The radius of growth-inhibition zones was recorded in millimeters.

Results

Antimicrobial effect was greater for CHX, followed by IKI and Ca(OH)2. 2% CHX inhibited significantly better the bacterial growth than 4% + 2% IKI (p < 0.05). Two percent CHX also exhibited a significantly greater antimicrobial effect than either of the concentrations of Ca(OH)2 tested. None of the combinations of medicaments exhibited a greater antimicrobial effect than 4% and 2% CHX tested individually.

Conclusions

4%, 2% and 1% CHX individually, exhibited the greatest antimicrobial effect followed by IKI with a moderate effect and Ca(OH)2 which exhibited only a discrete antimicrobial activity against F. nucleatum. The combination of intracanal medicaments did not increase the antimicrobial effects of the medicaments evaluated individually.