Root canal obturation

D. 0rstavik, Materials used for root canal obturation technical, biological and clinical testing, Endod. Topics 12 (2005) 25-38. 

E.O. Onay, M. Ungor, H. Orucoglu, An in vitro evaluation of the apical sealing ability of a new resin-based root canal obturation system, J. Endod. 32 (2006) 976-978. 

Alternative polymer systems have been developed for root canal obturation. These include a degradable polymer (polycaprolactone) and a bioactive glass (Elzubair et al., 2006). Similar to gutta percha, these materials are thermoplastic and can be heated and injected into the root canal. As before, however, there appears to be no rheological information about them in the literature. 

The most widely used means of obturating tooth roots following extirpation of the pulp is with gutta percha points which can be compressed into irregularly shaped root canals using either lateral or vertical compaction techniques (Fig. 10.1). These gutta percha points are usually warmed with a heated plugger, with an initial master point placed first, followed by accessory points as necessary to complete obturation [6]. 

C.R. Barthel, J. Moshonov, G. Shuping, D. 0rstavik, Bacterial leakage versus dye leakage in obturated root canals, InL Endod. J. 32 (1999) 370-375. 

M. Pawinska, A. Kierklo, G. Marczuk-Kolada, New technology in endodontics - the Resilon-Epiphany system for obturation of root canals, Adv. Med. Sci. 51 (Suppl. 1) (2006)154-157. 

In endodontic treatment, the aim is to completely seal the root canal. Traditionally this has been carried out with cones of gutta percha, also containing added zinc oxide, barium sulfate, plasticizers and coloring agents (Friedman et al, 1975), packed into the canal with a sealer - usually a cement containing zinc oxide and eugenol. A concern with this material system is that there is no adhesion between gutta percha and the sealer, or between the sealer and the tooth dentin. Further, complete adaptation of the material to completely obturate the root canal is not always achieved. 

Injectable thermoplasticized gutta percha systems have been developed in attempts to achieve good obturation - currently available systems have been reviewed by GUckman et al. (2000, 2001). These systems can be successful, but do not eliminate the need for careful shaping and cleaning of the root canal prior to filling. 

Several different types of material have been employed with varying degrees of clinical success in attempts to create a clinically effective impervious seal at the apex of the tooth root. The most successful and widely used approach is to use a combination of pre-formed obturating points and some sort of canal-sealing material. The latter are placed as high viscosity liquids that set more or less rapidly to form rigid materials that establish a close fit to the interior of the root that ideally seals the root. 

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