Original Research. An in vitro comparison between the apical sealing abilities of resilon with Epiphany sealer and gutta-percha with AH plus sealer

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1 Original Research An in vitro comparison between the apical sealing abilities of resilon with Epiphany sealer and gutta-percha with AH plus sealer Rajan T Lambor, Ida de Noronha de Ataide, Paul Chalakkal 1, Francis Akkara 2, Suhail Ahamed Shariff 3, Kristlee Sabrin Fernandes Departments of Conservative Dentistry and Endodontics, 1 Pedodontics and Preventive Dentistry, 2 Oral and Maxillofacial Surgery, Goa Dental College and Hospital, Bambolim, Goa, 3 Department of Prosthodontics, Yogita Dental College and Hospital, Ratnagiri, Maharashtra, India Received : Review completed : Accepted : ABSTRACT Context: The study assesses the apical sealing ability of two obturating materials (resilon and gutta-percha) with their sealants by means of the dye penetration method using India ink. Aims: To compare the resistance to apical dye penetration between resilon (with Epiphany sealer; Epiphany, Pentron clinical technologies, USA) and gutta-percha (with AH Plus sealer; Dentsply, Maillefer, Germany). It was hypothesized that there would be no difference between the two groups with regard to apical dye penetration. Settings and design: Hundred mandibular first premolars from individuals aged between 20 to 25 years were selected after their lengths were standardized. Materials and Methods: Instrumentation was performed with NiTi hand protaper files (Dentsply, Maillefer) using EDTA paste and copious irrigation with 2.5% sodium hypochlorite. Experimental group 1 consisted of roots that were treated with Epiphany primer and obturated with resilon (with Epiphany sealer). Experimental group 2 consisted of those obturated with gutta-percha using AH Plus sealer. The samples were immersed in blue India Ink and cleared using 5% nitric acid. Dye penetration was assessed under a stereomicroscope. Statistical analysis: Mann-Whitney U test. Results: Roots obturated with resilon core material and Epiphany sealer exhibited lesser mean apical dye penetration (1.281 mm; SD: 0.742) in comparison to those obturated with gutta-percha and AH plus sealer (2.154 mm; SD: 0.814). The difference was found to be highly significant (P<0.0025). Conclusion: Resilon (with Epiphany sealer) provided better radicular apical sealing in comparison to gutta percha (with AH Plus sealer). Key words: AH plus, Epiphany, gutta-percha, resilon, sealer A complete three-dimensional obturation of the root canal system is widely accepted as a critical factor for long term success of endodontic therapy. [1] The inability to fill and seal the root canal system has been reported to account for nearly 60% of root canal failures. [2] Address for correspondence: Dr. Paul Chalakkal atomheartpaul@yahoo.com Quick Response Code: Access this article online Website: PMID: *** DOI: / Gutta-percha is considered as the gold standard filling material for obturating root canals due to its biocompatibility, dimensional stability, compactibility, thermo plasticity and ease of removal. A sealer is used along with gutta-percha to fill the anatomical variations that cannot be mechanically debrided or chemically irrigated totally However, numerous studies have indicated that gutta-percha along with sealer are unable to seal the root canal system meticulously. [3-5] Hovland and Dumsha stated that all root canal sealers leak, but there is probably a critical level of leakage that is unacceptable which might lead to endodontic failure. They also found that leakage could occur at the interface between the sealer and dentin; sealer and gutta-percha; through the sealer itself; or by dissolution of the sealer. [6] Torabinejad et al. showed that when gutta-percha obturated canals were challenged by bacteria, 50% allowed bacterial

2 penetration through the entire length of the canal within 30 days. [7] Shipper and Trope showed that the use of the Fiberfill obturator (Pentron Clinical Technologies, Wallingford, CT; a resin fiber post with 5-8 mm of guttapercha apically) with a resin bonding sealer, resulted in 50% improvement in preventing bacterial leakage compared with standard gutta-percha techniques. They also suggested that a resin core root canal filling that could bond to the root canal walls would be desirable. [2] In order to improve obturation of the root canal system, new techniques and materials have been developed. One such material is resilon. The Resilon system (Epiphany, Pentron clinical technologies, USA) consists of a self-etch dentin primer, a dual-cure resin sealer and polyester polymer cones or pellets in various sizes. Resilon is a new thermoplastic, synthetic obturating material based on polyester chemistry that performs handles and looks like gutta-percha. The technique for using resilon is similar to most other bonding systems. Leakage tests are an accepted method to compare the seal of filling materials, even though a universally acceptable model does not exist. [8] The purpose of this study was to compare the resistance to apical dye penetration between resilon (with Epiphany sealer; Epiphany, Pentron clinical technologies, USA) and gutta-percha (with AH Plus sealer; Dentsply, Germany). MATERIALS AND METHODS Hundred mandibular first premolars (extracted for Orthodontic treatment) from individuals aged between 20 to 25 years were selected after they fulfilled the following criteria: All the teeth were single rooted with single canals; they were free of caries, cracks, resorption, malformed roots, calcified root canals and open apices. All teeth were thoroughly cleaned to remove calculus and stains. The teeth were then immersed in 5% sodium hypochlorite for 15 minutes to dissolve any tissue following which tissue remnants were mechanically debrided using a curette. All teeth were then stored in a solution of 0.2% thymol in normal saline. The crown of each tooth was removed at the cemento-enamel junction with a tapered fissure diamond bur (No. 852) to permit ideal access to the root canal. All roots were reduced to a standard length of 14 mm from the coronal surface to the apex of the root. An operating microscope (Carl Zeiss surgical Inc Thornwood, NY) was used to inspect the roots for cracks under magnification. The procedure for preparation and obturation was standardized for all groups and performed by the same operator by using hand instruments. The coronal access preparation for each tooth was made with an endo-access bur on a high-speed hand piece with water spray. The working length was determined by passing a # 15 K file into the canal until the tip was just visible at the apical foramen, and then subtracting 1 mm from this length. The apical stop was prepared at this level. Instrumentation was performed using the crown down technique with NiTi hand Protaper files (Dentsply, Maillefer). Apical gauging was done with#20 K file and canal preparation was carried out with Protaper files until finishing file F1. Instrumentation was performed with EDTA paste and copious irrigation with 2.5% sodium hypochlorite (NaOCl). The irrigant was delivered through a 25 gauge needle, which was placed as far as possible into the canal without letting it touch the canal walls. After cleaning and shaping, the canals were irrigated with 5ml of 17% EDTA for 1-2 minutes to remove any smear layer. On completion of instrumentation, a # 10 K file was passed through the apical foramen by 1 mm to ensure patency. The teeth were randomly divided into two experimental groups (groups 1 and 2) of 30 teeth each and four control groups (groups 3, 4, 5 and 6) of 10 teeth each. The canals were dried with paper points, and gutta-percha or resilon points that fitted with tug back at the working length were selected as master points. Group 1 (lateral condensation of resilon with epiphany sealer) After instrumentation, the self-etching Epiphany primer was placed into the canal with an applicator tip and excess primer was removed with paper points. Next, Epiphany sealer was placed using a lentulo spiral and the roots were obturated with resilon core material and Epiphany sealer. The Epiphany system was used according to the manufacturer s instructions. Lateral condensation with fine accessory resilon (0.06 taper; size 20-30) cones was performed until the root canal was filled. The coronal surface of the root filling was light-cured for 40 seconds to polymerize the surface of the dual cure sealer. Group 2 (lateral condensation of gutta-percha with AH plus sealer) These roots were filled with gutta-percha and AH Plus sealer (Dentsply, Maillefer, Germany) using cold lateral condensation technique. AH plus sealer was mixed and placed in the canal using a lentulo spiral after which gutta-percha cones (Kerr) were coated with the sealer and placed into the root canal up to working length. Lateral condensation with fine accessory gutta-percha cones (Dentsply, Maillefer) was performed until the root canal was completely filled. Group 3 (control resilon without sealer) In this group, roots were obturated with Resilon by lateral condensation without the Epiphany sealer. Group 4 (control gutta-percha without sealer) In this group, roots were obturated with gutta-percha by lateral condensation without the AH plus sealer.

3 Group 5 (control resilon group completely coated with nail polish) Similar to group 1 Group 6 (control gutta-percha group completely coated with nail polish) Similar to group 2 Roots from all groups were restored with glass ionomer cement (GC 9, GC Corporation, Tokyo, Japan) at the coronal end (to a depth of 3mm). Two layers of nail polish were painted over the root surfaces to seal them except for the apical 2 mm. However, the root surfaces of teeth in groups 5 and 6 were completely covered with nail polish. All samples were stored in saline solution at 37 C for 48 hours, following which tooth samples from each group were immersed in 40 ml of India ink at 37 C for 3 days. Thereafter they were thoroughly washed with physiological serum. Nail polish was removed carefully with a lecron carver, and the teeth were dried for 24 hours before clearing. The samples were cleared by placing them in 5% nitric acid to decalcify. The acid was changed daily and agitated three times a day. After decalcification, the samples were rinsed in running tap water. The dehydration process consisted of a series of 80% ethyl alcohol rinses for 12 hours, and 100% ethyl alcohol rinse for 24 hours to complete the dehydration process. The dehydrated samples were then placed in methyl salicylate till they were clear and transparent. The quality of apical seal of each specimen [Figures 1 and 2] was observed under a stereomicroscope with micrometer eye piece (Olympus SZX12, Japan). The amount of dye penetration was measured from the tip of the master cone to the most coronal extent of dye penetration within the root canal space. The amount of dye penetration was measured and recorded to the nearest 0.1 mm. Statistical analysis was performed using the Mann-Whitney U test for calculating ranks of dye penetration and the sum of ranks [P<0.0025; Tables 1 and 2]. RESULTS The roots that constituted the control groups (3 and 4) revealed leakage throughout the length of the root canal. The roots that constituted the control groups (5 and 6) revealed absence of penetration of the die into the canals. Roots obturated with resilon core material and Epiphany sealer exhibited lesser mean apical dye penetration [1.281 mm; SD: 0.742; Table 3] in comparison to those obturated with gutta-percha and AH plus sealer [2.154 mm; SD: 0.814; Table 3]. The difference was found to be highly significant [P<0.0025; Tables 1 and 2]. DISCUSSION Microleakage, whether coronally or apically, adversely affects the success of root canal therapy. [9] Many parameters influence microleakage during the course of root canal treatment like: isolation, patient cooperation, canal Table 1: Ranks of dye penetration (Mann-Whitney U Test) Groups Dye penetration Mann-Whitney U 167 P value Table 2: Sum of ranks (Mann-Whitney U Test) Groups Number Mean Rank Sum of Ranks Resilon and Epiphany Gutta-Percha and AH Plus Total 60 Table 3: Mean and standard deviation of dye penetration Groups Number Mean Std. Deviation Resilon and Epiphany sealer Gutta-Percha and AH Plus Figure 1: Stereomicroscopic view of apical dye penetration through a root canal obturated with gutta-percha and AH Plus sealer Figure 2: Stereomicroscopic view of apical dye penetration through a root canal obturated with resilon and Epiphany sealer

4 anatomy, root morphology, operator skill, root canal sealing, and the choice of filling material. [9,10] Achieving a hermetic seal is considered to be a major prerequisite for success after root canal treatment. According to accepted definitions, hermetic refers to-sealed against the escape or entry of air or made airtight by fusion or sealing. [11] The commonly used term hermetic seal is inaccurate because it is not air, but fluid that is present at the periapical region. The term Impermeable, would be more accurate. [12] According to Gutman, complete sealing of the root canal system is impossible with currently accepted materials. [13] Lateral condensation has been the most widely used method for obturating root canals. The advantages of this technique include its predictability; relative ease of use; and controlled placement of material. Resilon a thermoplastic synthetic polymer based root canal filling material has been developed, which has the same handling properties of gutta-percha. Resilon contains bioactive glass, bismuth oxychloride and barium sulphate. The overall filler content is approximately 65% by weight. Dual curable Epiphany sealer has a resin matrix that contains Bis GMA, ethoxylated Bis GMA, Urethane dimethacrylate and hydrophilic difunctional methacrylates. It contains filler composed of calcium hydroxide, barium sulphate, barium glass and silica. The total filler content in the sealer is approximately 70% by weight. Forty seconds of light cures the coronal 2mm of the canal, thereafter the entire filling self cures in approximately 15 to 30 minutes. Resilon can be softened and dissolved like gutta-percha with solvents like chloroform. [14] In this study, both the control groups exhibited complete dye penetration within 24 hours due to complete absence of sealers. Both the root canal filling materials and their associated sealers allowed some amounts of dye penetration. The mean value through resilon (with Epiphany sealer) was lower than that for gutta-percha (with AH Plus sealer). This difference was found to be highly significant (P<0.0025; Mann-Whitney U test), probably because of the attachment of Epiphany sealer to the root canal walls through its bonding agent. Adhesion to both, the obturation material and the dentin may also have contributed to its sealing property. The results of this study are in accordance with that of Shipper et al., who found that bacterial leakage through resilon and Epiphany sealer was significantly lesser than that through gutta-percha and AH plus sealer. [15] In another study, Shipper et al. compared bacterial leakage between gutta-percha (with AH Plus sealer) and resilon (with Epiphany sealer). The study utilized Enterococcus faecalis in addition to Streptococcus mutans. Again leakage was found to be significantly more through the former than the latter. [2] In an in vivo study by Shipper et al. in dog teeth, the periapical inflammatory response to microbial inoculation was lesser for those filled with resilon and Epiphany sealer, than those filled with gutta-percha and AH Plus sealer. [16] However, in a study by Tay et al., both Resilon (with Epiphany sealer) and gutta-percha (with AH Plus sealer) showed equivalent apical leakage which worsened if the smear layer was not removed. They also concluded that the quality of apical seal achieved with resilon and Epiphany sealer was not superior to that of gutta-percha and epoxyresin sealer. [17] In a recent study, there were no differences found between the different filling materials (gutta-percha/ Grossman sealer and Resilon/Epiphany) and obturation techniques (lateral condensation and system B technique) with respect to coronal or apical leakages. [18] In a study by Gesi et al., it was found that gutta-percha exhibited higher interfacial strength than Resilon. [19] Resilon is a relatively new material with several advantages like: It undergoes minimal shrinkage due to monoblock adhesion; enhances root strength; and superior sealing ability. It has also recently been found to increase the in vitro resistance to fracture of single canal teeth in comparison with those filled with gutta-percha. [20] Several methods have been employed to evaluate the apical sealing abilities of obturating materials, the most popular being the dye penetration method. However, certain drawbacks of using the methylene blue dye penetration method has been reported. [21] It has been found to get discolored while in contact with materials like amalgam, calcium hydroxide, Cavit, MTA and zinc oxide eugenol. [22] However, none of these materials were used in this study. It has also been shown that entrapment of air in root canals can cause failure in dye penetration. [23,24] Dye penetration into root canals is influenced by tooth age, which indirectly affects root dentin permeability. [25] However, in this study the teeth were obtained from young individuals aged between 20 and 25 years. India ink (2% methylene blue) has been shown to be a suitable indicator in evaluating root canal seal. [26] It has also been shown to be a more reliable tracer than 1% methylene blue, because no dissolution of sealers occur in contact with India ink. [27] The results from this study showed that the Epiphany obturating system has superior sealing properties in comparison to gutta-percha and AH plus sealer. However, the disadvantage of it being an in vitro study might not provide a conclusive comparison. Future in vivo studies comparing these materials are suggested. CONCLUSION Resilon obturating material (used with Epiphany sealer) provided better radicular apical sealing in comparison to gutta percha (used with AH Plus sealer).

5 REFERENCES 1. Kuhre AN, Kessler JR. Effect of moisture on the apical seal of laterally condensed gutta-percha. J Endod 1993;19: Shipper G, Trope M. In vitro microbial leakage of endodontically treated teeth using new and standard obturation techniques. J Endod 2004;30: de Oliveira DP, Barbizam JV, Trope M, Teixeira FB. Comparison between gutta-percha and resilon removal using two different techniques in endodontic retreatment. J Endod 2006;32: Weine FS, Wenckus CS. Canal filling with semisolid materials. In: Weine FS, editor. Endodontic Therapy. 6 th ed. St Louis: Mosby; p Smith JJ, Montgomery S. A comparison of apical seal: Chloroform versus halothane-dipped gutta-percha cones. J Endod 1992;18: Hovland EJ, Dumsha TC. Leakage evaluation in vitro of the root canal sealer cement Sealapex. Int Endod J 1985;18: Torabinejad M, Ung B, Kettering JD. in vitro bacterial penetration of coronally unsealed endodontically treated teeth. J Endod 1990;16: Ali Ghamdi A, Wennberg A. Testing of sealing ability of endodontic filling materials. Endod Dent Traumatol 1994;10: Beatty RG, Baker PS, Haddix J, Hart F. The efficacy of four root canal obturation techniques in preventing apical dye penetration. J Am Dent Assoc 1989;119: Schwartz RS, Fransman R. Adhesive dentistry and endodontics: Materials, clinical strategies and procedures for restoration of access cavities: A review. J Endod 2005;31: Johnson WT, Gutmann JL. Obturation of the cleaned and shaped root canal system. In: Cohen S, Hargreaves KM, editors. Pathways of the pulp. 9 th ed. St. Louis: Mosby; p Ingle JI, Newton CW, West JD, Gutmann JL, Glickman GN, Korzon B et al. Obturation of the radicular space. In: Ingle JI, Bakland LK, editors. Endodontics. 5 th ed. Canada: BC Decker; p Gutmann JL, Hovland EJ. Problem in root canal obturation. In: Gutman JL, Dumsha TC, Lovdahl PE, Hovland EJ, editors. Problem solving in endodontics.3 rd ed. St. Louis: Mosby; p Trope M, Debelian GJ. Root canal therapy: Clinical procedure. In: Trope M, Debelian GJ, editors. Endodontics manual for the general dentist. London: Quintessence Publishing; p Shipper G, Ørstavik D, Teixeira FB, Trope M. An evaluation of microbial leakage in roots filled with a thermoplastic synthetic polymer-based root canal filling material (Resilon). J Endod 2004;30: Shipper G, Teixeira FB, Arnold RR, Trope M. Periapical inflammation after coronal microbial inoculation of dog roots filled with gutta-percha or resilon. J Endod 2005;31: Tay FR, Loushine RJ, Weller RN, Kimbrough WF, Pashley DH, Mak YF et al. Ultra structural evaluation of the apical seal in roots filled with a polycaprolactone-based root canal filling material. J Endod 2005;31: de Almeida-Gomes F, Manigllia-Ferreira C, de Morais Vitoriano M. Ex vivo evaluation of coronal and apical microbial leakage of root canal filled with gutta-percha or Resilon/Epiphany root canal filling material. Indian J Dent Res 2010;21: Gesi A, Raffaelli O, Goracci C, Pashley DH, Tay FR, Ferrari M. Interfacial strength of Resilon and gutta-percha to intra radicular dentin. J Endod 2005;31: Baba SM, Grover SI, Tyagi V. Fracture resistance of teeth obturated with Gutta percha and Resilon: An in vitro study. J Conserv Dent 2010;13: Souza EM, Pappen FG, Shemesh H, Bonanato-Estrela C, Bonetti-Filho I. Reliability of assessing dye penetration along root canal fillings using methylene blue. Aust Endod J 2009;35: Wu MK, Kontakiotis EG, Wesselink PR. Decoloration of 1% methylene blue solution in contact with dental filling materials. J Dent 1998;26: Wu MK, De Gee AJ, Wesselink PR. Fluid transport and dye penetration along root canal fillings. Int Endod J 1994;27: Goldman M, Simmonds S, Rush R. The usefulness of dye-penetration studies reexamined. Oral Surg Oral Med Oral Pathol 1989;67: Thaler A, Ebert J, Petschelt A, Pelka M. Influence of tooth age and tooth section on root dentine dye penetration. Int Endod J 2008;41: Yoshikawa M, Noguchi K, Toda T. Effect of particle sizes in India ink on its use in evaluation of apical seal. J Osaka Dent Univ 1997;31: Oztan MD, Ozgey E, Zaimoglu L, Erk N. The effect of various root canal sealers on India ink and different concentrations of methylene blue solutions. J Oral Sci 2001;43: How to cite this article: Lambor RT, de Ataide Id, Chalakkal P, Akkara F, Shariff SA, Fernandes KS. An in vitro comparison between the apical sealing abilities of resilon with Epiphany sealer and gutta-percha with AH plus sealer. Indian J Dent Res 2012;23:694. Source of Support: Nil, Conflict of Interest: None declared.