Assessment of the Antibacterial Activity of Calcium Hydroxide Combined with Chlorhexidine Paste and Other Intracanal Medications against Bacterial Pathogens

Abstract

Objectives: The purpose of this study was to assess the in vitro antibacterial activity of four formulations of calcium hydroxide [Ca(OH)2] pastes against Enterococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa and Streptococcus mutans. Methods: A broth dilution test was performed, and the lengths of time for different pastes to kill the microbial cells were recorded and statistically analyzed. The following medications were assessed: Group I – Ca(OH)2 + 2.0% chlorhexidine (CHX) gel; Group II – Ca(OH)2 + camphorated paramonochlorophenol (CMCP) and propylene glycol; Group III – Ca(OH)2 + propylene glycol; Group IV – Ca(OH)2 + saline. Results: The results showed that E. faecalis was the most resistant microorganism. Groups II and III eliminated all the microbial cells in 15 seconds. Group I took 45 seconds to eliminate E. faecalis. Conclusions: Under the conditions of this study, it was concluded that all the intracanal medications tested showed antibacterial activity. However, the association of Ca(OH)2 and PMCC or Ca(OH)2 and propylene glycol showed a better performance, since Groups II and III took a shorter length of time than the other groups to eliminate S. aureus and E. faecalis. (Eur J Dent 2011;5:1-7)

Nonsurgical endodontic therapy along with minimal invasive treatment utilizing Bhasker's hypothesis for the management of infected radicular cystic lesion: A rare case report

“…Chlorhexine may also present residual antimicrobial activity on the dentine surface after prolonged contact within root canal and also improve antimicrobial efficacy against calcium hydroxide resistant microorganisms. [9] Therefore, used as root canal irrigants and as an intracanal dressing for asepsis of root canal in the present case.…”

Diffusion of Hydroxyl Ions from Calcium Hydroxide and Aloe vera Pastes

“…This drug was introduced in Endodontics in 1920 by Hermann and has been used in different clinical situations since then (2). The effects of CH include antimicrobial activity (2)(3)(4)(5), mechanical blocking to avoid re-infection of the root canal (5,6), capacity to limit root resorption (7,8), induces formation of mineralized tissue (5,6) and promotes repair of periapical and adjacent tissues (2,4).…”

“…Tronstad et al (8) suggested that CH in the root canals promotes a pH increase on the external root surface, thus promoting alkalinization of resorption areas on the root surface, by diffusion of hydroxyl ions through the dentinal tubules. Other important characteristic of the dissociation of CH into hydroxyl ions is the ability to inactivate bacterial lipopolysaccharide (LPS), a toxin produced by Gram-negative bacteria commonly found in the root canal system (4,6).…”

“…Different vehicles are added to improve the qualities of CH, which may influence its diffusion and dissociation through the root canal system (5,6,10,11). The vehicle used for this association should allow efficient dissociation of hydroxyl ions for a satisfactory action of CH (2,4,12,13).…”

Antibacterial activity of calcium hydroxide combined with chitosan solutions and the outcomes on the bond strength of RealSeal sealer to radicular dentin

“…Nevertheless, E. faecalis has been found to be resistant to this effect due to its capability to go through the dentinal tubules and adapt to altering environments[11]. Various antibacterial agents have been introduced, such as chlorohexidine, metronidazole, bioactive glass, or their combination with Ca(OH) 2 , which were found to be more efficient than Ca(OH) 2 alone in minimizing the number of E. faecalis , with varying degrees of success[12],[13]. Consequently, the discovery and development of the medicaments to control the infection of root canal is urgently needed.…”