Endodoncia

doi:10.1111/j.1365-2591.2006.01197.x

REVIEW

Antibacterial efficacy of calcium hydroxide intracanal dressing: a systematic review and meta-analysis

C. Sathorn, P. Parashos & H. Messer
Endodontic Unit, School of Dental Science, The University of Melbourne, Melbourne,Vic. Australia

Abstract
Sathorn C, Parashos P, Messer H. Antibacterial efficacy of
calcium hydroxide intracanal dressing:a systematic review and meta-analysis. International Endodontic Journal, 40, 2–10, 2007.

Aim To determine to what extent does calcium hydroxide intracanal medication eliminate bacteria from human root canals, compared with the same canals before medication, as measured by the number of positive cultures, in patients undergoing root canal treatment for apical periodontitis (teeth with aninfected root canal system). Methodology CENTRAL, MEDLINE and EMBASE databases were searched. Reference lists from identified articles were scanned. A forward search was undertaken on the authors of the identified articles. Papers that had cited these articles were also identified through the Science Citation Index to identify potentially relevant subsequent primary research. Review methods The includedstudies were pre-/ post-test clinical trials comparing the number of

positive bacterial cultures from treated canals. Data in those studies were independently extracted. Risk differences of included studies were combined using the generic inverse variance and random effect method. Results Eight studies were identified and included in the review, covering 257 cases. Sample size varied from 18 to 60cases; six studies demonstrated a statistically significant difference between pre- and post-medicated canals, whilst two did not. There was considerable heterogeneity among studies. Pooled risk difference was )21%; 95% CI: )47% to 6%. The difference between pre- and post-medication was not statistically significant (P ¼ 0.12). Conclusions Calcium hydroxide has limited effectiveness in eliminatingbacteria from human root canal when assessed by culture techniques. Keywords: canal disinfection, infection control, microbiology.
Received 28 April 2006; accepted 3 August 2006

Introduction
Calcium hydroxide has been used in dentistry for almost a century (Siqueira & Lopes 1999). Its use in root canal treatment as an intracanal medication has been associated with periradicular healing(Sjogren ¨ et al. 1990) and few adverse reactions (De Moor & De Witte 2002). Its use in root canal treatment was
Correspondence: Dr Chankhrit Sathorn, 720 Swanston Street, Melbourne, Vic. 3010, Australia (Tel.: +613 9341 1521; fax: +613 9341 1599; e-mail: chankhrit@gmail.com).

promoted by a series of papers (Bystrom & Sundqvist ¨ 1985, Bystrom et al. 1985) documenting the antibac¨ terial efficacy ofcalcium hydroxide in human root canals. Subsequent studies substantiated these reports (Ørstavik et al. 1991, Sjogren et al. 1991), and the ¨ routine use of calcium hydroxide as an inter-appointment intracanal medicament became widespread. Apical periodontitis is caused by bacteria within the canal space (Kakehashi et al. 1965, Moller et al. ¨ 1981). The treatment of apical periodontitis should,therefore, aim at bacterial eradication. Because cleaning and shaping procedures alone do not reliably

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International Endodontic Journal, 40, 2–10, 2007

ª 2006 International Endodontic Journal

Sathorn et al. Antibacterial efficacy of calcium hydroxide

eliminate bacteria (Bystrom & Sundqvist 1981, ¨ Dalton et al. 1998), it seems logical to medicate canals with an antibacterial agentafter canal preparation. Recently, the ability of calcium hydroxide medication to eradicate completely bacterial species from the root canal has been questioned. For example, ex vivo studies have shown that dentine can inactivate the antibacterial activity of calcium hydroxide (Haapasalo et al. 2000, Portenier et al. 2001) and one clinical study (Peters et al. 2002) has shown that the number of...