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DOI: 10.4103/2278-9626.112317
Evaluation of root canal smear layer removal by two types of lasers: A scanning electron microscopy study
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Abstract
Objective: This study was to compare the effects of Erbium: Yttrium-Aluminium-Garnet (Er: YAG), and Neodimium: Yttrium-Aluminium-Garnet (Nd: YAG) lasers on removing the smear layer using scanning electron microscopy. Background: Removing Smear layer and exposure of dentinal tubules facilitate a tight-fitting root canal filling, which is necessary for a successful endodontic treatment and one of the proposed methods for removing the smear layer is the use of lasers. Materials and Methods: In this experimental study, 55 human single-rooted teeth were examined. Instrumentation was done using the step-back technique with hand files up to file #40 at the apical area and file #80 at the coronal area. The samples were divided into three groups: Samples irradiated by the Er: YAG laser (1 W, 10 Hz, 130.7 J/cm2 ) in Group 1 (n=25), the Nd: YAG laser (2 W, 15 Hz, 188.25 J/cm2 ) in Group 2 (n=25) and samples irrigated by 5.25% NaOCl as the control in Group 3 (n=5). Next, roots were bisected longitudinally and prepared for scanning electron microscopy. Data were analyzed using the Kruskal-Wallis, Mann-Whitney, Friedman and Wilcoxon tests (P<0.05). Results: The Er: YAG laser can remove more of the smear layer from the root canal wall than the Nd: YAG laser (P=0.000). Comparisons between three regions showed that both of the lasers proved less efficient in apical parts of the root canal. Conclusion: Based on the findings of the present study, irradiation by the Er: YAG laser was more effective in smear layer removal than the Nd: YAG laser.
Keywords
Erbium: Yttrium-Aluminium-Garnet laser - neodymium: Yttrium-aluminum-garnet laser - smear layerPublication History
Article published online:
01 November 2021
© 2013. European Journal of General Dentistry. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/.)
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References
- 1 Shokouhinejad N, Sharifian MR, Aligholi M, Assadian H, Tabor RK, Nekoofar MH. The sealing ability of resilon and gutta-parcha following different smear layer removal methods: An ex vivo study. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010;110:e45-9.
- 2 McComb D, Smith DC. A preliminary scanning electron microscopic study of root canals after endodontic procedures. J Endod 1975;1:238-42.
- 3 Mello I, Coil J, Antoniazzi JH. Does a final rinse to remove smear layer interfere on dentin permeability of root canals? Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009;107:e47-51.
- 4 Torabinejad M, Handysides R, Khademi AA, Bakland LK. Clinical implications of the smear layer in endodontics: A review. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2002;94:658-66.
- 5 Violich DR, Chandler NP. The smear layer in endodontics: A review. Int Endod J 2010;43:2-15.
- 6 Shahravan A, Haghdoost AA, Adl A, Rahimi H, Shadifar F. Effect of smear layer on sealing ability of canal obturation: A systematic review and meta-analysis. J Endod 2007;33:96-105.
- 7 Mancini M, Armellin E, Casaglia A, Cerroni L, Cianconi L. A comparative study of smear layer removal and erosion in apical intraradicular dentine with three irrigating solutions: A scanning electron microscopy evaluation. J Endod 2009;35:900-3.
- 8 Pérez-Heredia M, Ferrer-Luque CM, González-Rodríguez MP, Martín-Peinado FJ, González-López S. Decalcifying effect of 15% EDTA, 15% citric acid, 5% phosphoric acid and 2.5% sodium hypochlorite on root canal dentine. Int Endod J 2008;41:418-23.
- 9 DiVito E, Peters OA, Olivi G. Effectiveness of the erbium: YAG laser and new design radial and stripped tips in removing the smear layer after root canal instrumentation. Lasers Med Sci 2012;27:273-80.
- 10 Schoop U, Goharkhay K, Klimscha J, Zagler M, Wernisch J, Georgopoulos A, et al. The use of the erbium, chromium: Yttrium-scandium-gallium-garnet laser in endodontic treatment: The results of an in vitro study. J Am Dent Assoc 2007;138:949-55.
- 11 Moritz A, Gutknecht N, Goharkhay K, Schoop U, Wernisch J, Sperr W. In vitro irradiation of infected root canals with a diode laser: Results of microbiologic, infrared spectrometric, and stain penetration examinations. Quintessence Int 1997;28:205-9.
- 12 Onal B, Ertl T, Siebert G, Müller G. Preliminary report on the application of pulsed CO 2 laser radiation on root canals with AgCl fibers: A scanning and transmission electron microscopic study. J Endod 1993;19:272-6.
- 13 Takeda FH, Harashima T, Kimura Y, Matsumoto K. A comparative study of the removal of smear layer by three endodontic irrigants and two types of laser. Int Endod J 1999;32:32-9.
- 14 Harashima T, Takeda FH, Zhang C, Kimura Y, Matsumoto K. Effect of argon laser irradiation on instrumented root canal walls. Endod Dent Traumatol 1998;14:26-30.
- 15 Schoop U, Barylyak A, Goharkhay K, Beer F, Wernisch J, Georgopoulos A, et al. The impact of an erbium, chromium: Yttrium-scandium-gallium-garnet laser with radial-firing tips on endodontic treatment. Lasers Med Sci 2009;24:59-65.
- 16 Hibst R, Keller U. Experimental studies of the application of the Er: YAG laser on dental hard substances: I. Measurement of the ablation rate. Lasers Surg Med 1989;9:338-44.
- 17 Keller U, Hibst R. Ablative effect of an Er: YAG laser on enamel and dentin. Dtsch Zahnarztl Z 1989;44:600-2.
- 18 Hibst R. Lasereinsatz in der zahnmedizin. Med Tech 1999;4:18-23.
- 19 Keller U, Raab WH, Hibst R. Pulp reactions during Erbium YAG laser irradiation of hard tooth structure. Dtsch Zahnarztl Z 1991;46:158-60.
- 20 Keller U, Hibst R. Ablative effect of an Er: YAG laser on enamel and dentin. Dtsch Zahnarztl Z. 1989;44:600-2.
- 21 Schoop U, Moritz A, Kluger W, Patruta S, Goharkhay K, Sperr W, et al. The Er: YAG laser in endodontics: Results of an in vitro study. Lasers Surg Med 2002;30:360-4.
- 22 White JM, Goodis HE, Cohen JN. Bacterial reduction of contaminated dentine by Nd: YAG laser. J Dent Res 1991;70:412.
- 23 Khademi A, Yazdizadeh M, Feizianfard M. Determination of the minimum instrumentation size for penetration of irrigants to the apical third of root canal systems. J Endod 2006;32:417-20.
- 24 Kouchi Y, Ninomiya J, Yasuda H, Fukui K, Moriyama T, Okamoto H. Location of Streptococcus mutans in the dentinal tubules of open infected root canals. J Dent Res 1980;59:2038-46.
- 25 Berutti E, Marini R, Angeretti A. Penetration ability of different irrigants into dentinal tubules. J Endod 1997;23:725-7.
- 26 Sasaki KM, Aoki A, Ichinose S, Ishikawa I. Ultrastructural analysis of bone tissue irradiated by Er: YAG Laser. Lasers Surg Med 2002;31:322-32.
- 27 Lee BS, Lin CP, Hung YL, Lan WH. Structural changes of Er: YAG laser-irradiated human dentin. Photomed Laser Surg 2004;22:330-4.
- 28 Barbakow F, Peters O, Havranek L. Effects of Nd: YAG lasers on root canal walls: A light and scanning electron microscopic study. Quintessence Int 1999;30:837-45.
- 29 Kivanç BH, Ulusoy OI, Görgül G. Effects of Er: YAG laser and Nd: YAG laser treatment on the root canal dentin of human teeth: A SEM study. Lasers Med Sci 2008;23:247-52.
- 30 Goya C, Yamazaki R, Tomita Y, Kimura Y, Matsumoto K. Effects of pulsed Nd:YAG laser irradiation on smear layer at the apical stop and apical leakage after obturation. Int Endod J 2000;33:266-71.
- 31 Esteves-Oliveira M, de Guglielmi CA, Ramalho KM, Arana-Chavez VE, de Eduardo CP. Comparison of dentin root canal permeability and morphology after irradiation with Nd: YAG, Er: YAG, and diode lasers. Lasers Med Sci 2010;25:755-60.
- 32 Zhang C, Kimura Y, Matsumoto K, Harashima T, Zhou H. Effects of pulsed Nd: YAG laser irradiation on root canal wall dentin with different laser initiators. J Endod 1998;24:352-5.
- 33 White JM, Fagan MC, Goodis HE. Intrapulpal temperatures during pulsed Nd: YAG laser treatment of dentin, in vitro. J Periodontol 1994;65:255-9.
- 34 Armengol V, Jean A, Rohanizadeh R, Hamel H. Scanning electron microscopic analysis of diseased and healthy dental hard tissues after Er: YAG laser irradiation: In vitro study. J Endod 1999;25:543-6.
- 35 Yasuda Y, Kawamorita T, Yamaguchi H, Saito T. Bactericidal effect of Nd: YAG and Er: YAG lasers in experimentally infected curved root canals. Photomed Laser Surg 2010;28:S75-8.