Research Article Discoloration of Roots Caused by Residual Endodontic Intracanal Medicaments Belinda Kuan-Jung Chen, 1 Roy George, 1 and Laurence James Walsh 2 1 School of Dentistry and Oral Health, Grifth University, Gold Coast Campus, Southport 4215, Australia 2 Te School of Dentistry, University of Queensland, Brisbane, QLD 4000, Australia Correspondence should be addressed to Roy George; drroygeorge@gmail.com Received 31 August 2013; Accepted 26 November 2013; Published 9 February 2014 Academic Editors: S. R. Fidel and G. Plotino Copyright © 2014 Belinda Kuan-Jung Chen et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Aims. Tis study examined the extent to which intervisit corticosteroid-based antibiotic pastes (CAP) medicaments contribute to staining of tooth structure afer attempted removal by irrigation techniques. Methods. A total of 140 roots were prepared and the canals were flled with Ledermix paste (demeclocycline), Odontopaste (clindamycin), and Doxypaste (doxycycline). Te pastes were removed afer 2 or 4 weeks of storage in the dark using EDTA and NaOCl with either a 27-gauge-slotted needle or an EndoActivator (Dentsply). Te roots were then exposed to an intense light source for 30 minutes each week and photographed afer a further 1, 3, or 6 months. Digital images were standardized and data for changes in luminosity were analysed using repeated measures ANOVA and a post hoc test. Results. Removal of the medicament did not prevent later discolouration. Tere was no signifcant diference between the paste removal methods. Ledermix paste caused the greatest darkening compared to the untreated controls, for both application periods and both methods of removal. Doxypaste and Odontopaste caused less darkening than Ledermix. Conclusion. Medicaments that stain teeth may continue to discolour teeth despite best attempts to remove them. Tis study stresses the importance of material selection and minimising contact of Ledermix within the coronal aspects of teeth. 1. Introduction Corticosteroid-based antibiotic-containing pastes (CAP) are used as short- and medium-term intracanal medicaments because they exert both anti-infammatory and antibiotic actions [1–11], which are useful in managing periapical infammation and root resorption [1, 2, 10, 12–18]. Difusion of triamcinolone and demeclocycline from the CAP product Ledermix (Lederle Pharmaceuticals, Wolfratshausen, Ger- many), which contains 1% triamcinolone acetonide and 3.21% demeclocycline HCl, through radicular dentine occurs readily, reaching a peak afer only two hours [19]. Te rate of release of demeclocycline falls to less than one-tenth of the initial release rate by the 7th day [1, 3, 6, 19, 20]. Binding of demeclocycline from CAP to dentine and its subsequent photooxidation when exposed to light can cause intense staining [7, 19, 21]. To address this potential problem, other CAP have been developed, including Odontopaste (Australian Dental Manufacturing, Brisbane, Australia) with 1% triamcinolone acetonide and 5% clindamycin HCl and Doxypaste (Ozdent, Castle Hill, Australia) with 1% triam- cinolone acetonide and 3% doxycycline hyclate. All three pastes contain the same underlying vehicle of polyethylene glycol to which various excipients and fllers are added, which do not exert antimicrobial activities. Compared with demeclocycline, doxycycline is more active as an antibiotic [22, 23] and poses less risk of staining [24]. Past laboratory studies of root discolouration from use of Ledermix CAP demonstrated an efect of ambient sunlight [9, 10], but the irradiation parameters could not be controlled rigidly in terms of irradiance and fuence. Clinical studies likewise demonstrate discolouration of replanted avulsed teeth over 12 months from Ledermix CAP placed into the root for 60–90 days [15]. Recommendations for use of CAP range from two weeks to two months [25]. It is unknown whether existing methods of removing CAP, such as fushing the root canal system using Hindawi Publishing Corporation e Scientific World Journal Volume 2014, Article ID 404676, 7 pages http://dx.doi.org/10.1155/2014/404676