[A evaluation of chlorhexidine as an endosonic irrigan]

Chlorhexidine has been utilized as a root canal irrigant since 1971. It is a broad-spectrum antimicrobial agent with minimal toxicity and residual long-term antibacterial capability. Although a sodium hypochlorite solution has been shown to have a better antimicrobial effect than chlorhexidine, its corrosive effect has prevented its further use especially since the in vitro antimicrobial effect of chlorhexidine has been shown to not be much less. However, the efficacy of chlorhexidine as an endodontic irrigant and intracanal medicament, requires further research in vivo. Therefore, in this study, the clinical effects of chlorhexidine were evaluated by comparing its antimicrobial properties with other endodontic irrigants. One hundred and fifty teeth were selected and evenly divided into 6 groups according to their pathological status. The root cancals were prepared with conventional hand filing or ultrasonic filing, respectively, and were rinsed singly with either chlorhexidine, EDTA or distilled water. The contents of each root canal before or after debridement were cultured in an incubator. The results showed that chlorhexidine with hand filing in one week and with endosonics in 48 hours had a better antimicrobial effect than did EDTA. As compared with the control group (distilled water), chlorhexidine showed marked antimicrobial effect in both hand and endosonic filing. It is concluded that chlorhexidine has an antibacterial effect as an endodontic irrigant in clinical applications.