Calcium hydroxide sealers

Leakage around calcium hydroxide sealers has been studied experimentally, and findings have generally been satisfactory [34-36]. However, there have been some adverse reports [37], and these variations have been attributed to crucial differences in experimental methods [38]. Leakage appears to be related to both the solubility of the material and the questionable adhesion to both the dentine walls and the gutta percha points. The calcium hydroxide sealer Apexit, for example, was found to have a high solubility when set compared with other types of endodontic sealer [39] and, in some studies, sealer particles have been found to occur with the tissues at a considerable distance from the sample [40,41],... 

A particular advantage of calcium hydroxide sealers is their anti-bacterial nature, a feature which is related to their high pH. Several in vitro studies have demonstrated that these show considerable anti-bacterial activity [42-44]. Despite their biocidal character, these materials are less toxic than zinc oxide-eugenol sealers towards human periodontal ligament cells [40,41]. 

The epoxy sealer AH26 Plus has been shown to have reasonable anti-bacterial properties [43]. In a comparative study of several different types of endodontic sealer, it was found to be as effective as Grossman s sealer in reducing the number of cultivable cells of Enterococcus faecalis. By contrast, the calcium hydroxide sealers Apexit and Sealapex were not effective at aU in reducing the number of these cells. 

F. Sleder, M. Ludlow, J. Bohacek, Long-term sealing ability of a calcium hydroxide sealer, J. Endod. 17 (1991) 541-543. 

Huang, T.H., Lee, H., and Kao, C.T., Evaluation of the genotoxicity of zinc oxide eugenol-based, calcium hydroxide-based, and epoxy resin-based root canal sealers by comet assay, J. Endod., 27,744,2001. 

L. Tronstad, F. Barnett, M. Flax, Solubility and biocompatibility of calcium hydroxide-containing root canal sealers, Endod. Dent. Traumatol. 4 (1988) 152-159. 

As described in Chapter 9, the main use of calcium hydroxide is as a pulp capping material. It is also used as a medicament for intra-canal treatment and in some apexification procedures [30], In addition, following pioneering studies in the late 1970s [31], it has also become used as the main active component of a group of proprietary root canal sealers. 

The physical properties of calcium hydroxide materials are acceptable for their use as endodontic sealers. They flow well in their unset state, so they can reach and seal the apical foramen of the affected tooth, and also adapt to the shape of any irregularities of the dentinal wall. 

Overall, calcium hydroxide materials appear satisfactory as endodontic sealers in clinical service [47,48], though they are not outstanding in this application [30]. Established brands continue to be made available for practitioners, and clearly find favour with certain members of the profession. They must be... 

L.S. Desai, N. Chandler, Calcium hydroxide-based root canal sealers a review, J. Endod. 35 (2009) 475 80. 

I. Soares, F. Goldberg, E. Massone, I.M. Soares, Periapical tissue response to two calcium hydroxide containing endodontic sealers, J. Endod. 16 (1990) 166-169. 

Z. Fuss, E. Weiss, M. Shalhav, Antimicrobial activity of calcium hydroxide containing endodontic sealers in Enterococcus faecalis in vitro, Int. Endod. J. 30 (1997) 397 02. 

F. Huang, K. Tai, M. Chou, Y. Chang, Cytotoxicity of resin zinc oxide-eugenol and calcium hydroxide based root canal sealers on human periodontal ligament cells and permanent V79 cells, Int. Endod. J. 35 (2002) 153-158. 

---