Push-out bond strength and fracture modes of MTA and bioactive glass-based sealers using different final irrigants: an in-vitro study

INTRODUCTION. The bond between gutta-percha and sealer is crucial for successful root canal (RC) filling, requiring sealers with optimal physical, chemical, and biological characteristics. Newer sealers aim to improve clinical outcomes, especially when smear layer removal enhances sealer flow and adhesion. This study compares the push-out bond strength (POBS) and failure modes of an MTA-based bioceramic sealer and a bioactive glass (BG)-based sealer using four different final irrigants.

MATERIALS AND METHODS. Eighty single-rooted mandibular premolars were decoronated to a length of 16 mm and prepared using ProTaper Gold rotary files with intermittent irrigation using 5.25% NaOCl. Samples were categorised into two main groups depending on the sealer employed [n = 40 (Nishika Canal Sealer BG and MTA Fillapex)] and further into four sub-groups according to the final irrigant [n = 10 (10% glycolic acid, MTAD, 18% Etidronic acid and normal saline). Following obturation with gutta-percha, the specimens were incubated at 37°C and 95% humidity. POBS was evaluated using a universal testing machine, and failure modes were analysed under a scanning electron microscope.

RESULTS. POBS obtained from the study were in the following order: Nishika Canal Sealer BG + Etidronic acid > MTA Fillapex + etidronic acid > Nishika canal sealer BG + glycolic acid > MTA Fillapex + glycolic acid > Nishika canal sealer BG + Normal saline > MTA Fillapex + MTAD > MTA Fillapex + normal saline > Nishika canal sealer BG + MTAD.

CONCLUSIONS. All irrigants used allowed proper setting of both sealers. This study indicates that the choice of chelating agent affects bond strength, with etidronic acid showing the highest dislodgement resistance for both sealers, while MTAD showed the lowest.

1. Trivedi S., Chhabra S., Bansal A., Kukreja N., Mishra N., Trivedi A. et al. Evaluation of sealing ability of three root canal sealers: An in vitro study. J Contemp Dent Pract. 2020;21(3):291–295. https://doi.org/10.5005/jp-journals-10024-2768

2. Huang G., Liu S.Y., Qiu D., Dong Y.M. Effect of a bioactive glass-based root canal sealer on root fracture resistance ability. J Dent Sci. 2023;18(1):27–33. https://doi.org/10.1016/j.jds.2022.08.004

3. Jafari F., Samadi Kafil H., Jafari S., Aghazadeh M., Momeni T. Antibacterial activity of MTA Fillapex and AH 26 root canal sealers at different time intervals. Iran Endod J. 2016;11(3):192–197. https://doi.org/10.7508/iej.2016.03.009

4. Washio A., Morotomi T., Yoshii S., Kitamura C. Bioactive glass-based endodontic sealer as a promising root canal filling material without semisolid core materials. Materials. 2019;12(23):3967. https://doi.org/10.3390/ma12233967

5. Alamoudi R.A. The smear layer in endodontic: To keep or remove – an updated overview. Saudi Endodontic Journal. 2019;9(2):71–81. https://doi.org/10.4103/sej.sej_95_18

6. Taşan A., Özlek E. Effects of ethylenediaminetetraacetic acid, citric acid, and etidronic acid on root dentin mineral content and bond strength of a bioceramic-based sealer: A scanning electron microscopyenergy dispersive spectroscopy study. J Dent Res Dent Clin Dent Prospects. 2024;18(1):37–43. https://doi.org/10.34172/joddd.40798

7. Neelakantan P., Varughese A.A., Sharma S., Subbarao C.V., Zehnder M., De-Deus G. Continuous chelation irrigation improves the adhesion of epoxy resin-based root canal sealer to root dentine. Int Endod J. 2012;45(12):1097–1102. https://doi.org/10.1111/j.1365-2591.2012.02073.x

8. Gupta K., Shetty S.S., Tandale A.B., Srikurmam M., Nihalani H. Comparative evaluation of continuous and sequential chelation on the dentinal tubule penetration of bioceramic-based sealer – A confocal laser scanning microscopic study. J Conserv Dent Endod. 2024;27(9):935–941. https://doi.org/10.4103/JCDE.JCDE_288_24

9. Arias-Moliz M.T., Ordinola-Zapata R., Baca P., Ruiz-Linares M., Ferrer-Luque C.M. Antimicrobial activity of a sodium hypochlorite/etidronic acid irrigant solution. J Endod. 2014;40(12):1999–2002. https://doi.org/10.1016/j.joen.2014.07.031

10. Srikumar G.P., Sekhar K.S., Nischith K.G. Mixture tetracycline citric acid and detergent – A root canal irrigant. A review. J Oral Biol Craniofac Res. 2013;3(1):31–35. https://doi.org/10.1016/j.jobcr.2012.09.001

11. Barcellos D.P.D.C., Farina A.P., Barcellos R., Souza M.A., Borba M., Bedran-Russo A.K. et al. Effect of a new irrigant solution containing glycolic acid on smear layer removal and chemical / mechanical properties of dentin. Sci Rep. 2020;10(1):7313. https://doi.org/10.1038/s41598-020-64450-1

12. Rebolloso de Barrio E., Pérez-Higueras J.J., García-Barbero E., Gancedo-Caravia L. Effect of exposure to etidronic acid on the bond strength of calcium silicate-based cements after 1 and 21 days: an in vitro study. BMC Oral Health. 2021;21(1):591. https://doi.org/10.1186/s12903-021-01959-5

13. Błaszczyk-Pośpiech A., Struzik N., Szymonowicz M., Sareło P., Wiśniewska-Wrona M., Wiśniewska K. et al. Endodontic sealers and innovations to enhance their properties: A current review. Materials. 2025;18(18):4259. https://doi.org/10.3390/ma18184259

14. Jaganath B.M., Rudranaik S., Krishnegowda S.C., Nirmala K.B., Nagashetty Y.H. Comparative evaluation of push-out bond strength and mode of failure of three different obturating materials: An in vitro study. J Conserv Dent Endod. 2024;27(6):608–612. https://doi.org/10.4103/JCDE.JCDE_186_24

15. Wang Y., Tang M., Yang X., Yang J. Evaluating the penetration, interfacial adaptation, and push-out bond strength of four bioceramic-based root canal sealers. BMC Oral Health. 2025;25(1):748. https://doi.org/10.1186/s12903-025-06124-w

16. Santana F.-R., Soares C.-J., Ferreira J.-M., Valdivi A.-D.-C., Souza J.-B., Estrela C. Effect of root canal sealer and artificial accelerated aging on fibreglass post bond strength to intraradicular dentin. J Clin Exp Dent. 2014;6(4):e350–e356. https://doi.org/10.4317/jced.51465

17. Khabadze Z., Mordanov O., Mehta V., Aggarwal S. Analysis of the effect of artificial aging on the phase composition of zirconia dominated by the cubic and tetragonal phases with polished and glazed surfaces: An in vitro study. J Conserv Dent Endod. 2025;28(7):647–653. https://doi.org/10.4103/JCDE.JCDE_266_25

18. Al-Haddad A., Che Ab Aziz Z.A. Bioceramic-based root canal sealers: A review. Int J Biomater. 2016;2016:9753210. https://doi.org/10.1155/2016/9753210

19. Akcay M., Arslan H., Durmus N., Mese M., Capar I.D. Dentinal tubule penetration of AH Plus, iRoot SP, MTA fillapex, and guttaflow bioseal root canal sealers after different final irrigation procedures: A confocal microscopic study. Lasers Surg Med. 2016;48(1):70–76. https://doi.org/10.1002/lsm.22446

20. Caceres C., Larrain M.R., Monsalve M., Peña Bengoa F. Dentinal tubule penetration and adaptation of Bio-C Sealer and AH-Plus: A comparative SEM evaluation. Eur Endod J. 2021;6(2):216–220. https://doi.org/10.14744/eej.2020.96658

21. Kumar D.S., Sanjeev D.K., Sekar D.M. Evaluation of physico chemical properties, cell viability and mineralization potential of New Pozzolan (fly Ash)-Based Mineral Trioxide Aggregate cement. J Oral Biol Craniofac Res. 2022;12(6):847–852. https://doi.org/10.1016/j.jobcr.2022.09.014

22. Nikhil V., Bansal P., Sawani S. Effect of technique of sealer agitation on percentage and depth of MTA Fillapex sealer penetration: A comparative in-vitro study. J Conserv Dent. 2015;18(2):119–123. https://doi.org/10.4103/0972-0707.153073

23. Chang S.W. Chemical characteristics of mineral trioxide aggregate and its hydration reaction. Restor Dent Endod. 2012;37(4):188–193. https://doi.org/10.5395/rde.2012.37.4.188

24. Mohammadi Z., Shalavi S., Jafarzadeh H. Ethylenediaminetetraacetic acid in endodontics. Eur J Dent. 2013;7(Suppl. 1):S135–S142. https://doi.org/10.4103/1305-7456.119091

25. Novozhilova N., Babina K., Polyakova M., Sokhova I., Sherstneva V., Zaytsev A. et al. The effect of different compositions and concentrations of etidronate-containing irrigants on the antibacterial activity of sodium hypochlorite against Enterococcus faecalis and Candida albicans. Dent J. 2024;12(3):46. https://doi.org/10.3390/dj12030046

26. Shetty N., Shetty P., Bhat R., D’cunha K., Shanavaz M.I. Etidronic acid as a root canal irrigant: A systematic review of its efficacy in disinfection and potential to enhance endodontic treatment outcomes. South East Eur J Public Health, 2024;25(S2):1519–1529. Available at: https://www.seejph.com/index.php/seejph/article/view/2922 (accessed: 13.12.2025).

27. Tartari T., Duarte Junior A.P., Silva Júnior J.O., Klautau E.B., Silva E Souza Jr M.H., Silva E Souza Jr P.A. Etidronate from medicine to endodontics: effects of different irrigation regimes on root dentin roughness. J Appl Oral Sci. 2013;21(5):409–415. https://doi.org/10.1590/1679-775720130201

28. El-Desoki H.S., Sadek H.S., Morsy D.A. Effect of glycolic acid as single irrigant versus sodium hypochlorite and EDTA on enterococcus faecalis count and smear layer removal in single-rooted teeth (an in vitro study). Int J Appl Dent Sci. 2023;9(2):109–118. https://doi.org/10.22271/oral.2023.v9.i2b.1720

29. Bello Y.D., Farina A.P., Souza M.A., Cecchin D. Glycolic acid: Characterization of a new final irrigant and effects on flexural strength and structural integrity of dentin. Mater Sci Eng C Mater Biol Appl. 2020;106:110283. https://doi.org/10.1016/j.msec.2019.110283

30. Kalaiselvam R., Govindaraju L., Thiyagarajan J., Perumal S., Rajendran M.R. Influence of glycolic acid as a chelating agent for smear layer removal and its effect on the microhardness of root canal dentin – A systematic review. J Conserv Dent Endod. 2025;28(2):112–118. https://doi.org/10.4103/JCDE.JCDE_679_24

31. Sayin T.C., Cehreli Z.C., Deniz D., Akcay A., Tuncel B., Dagli F. et al. Time-dependent decalcifying effects of endodontic irrigants with antibacterial properties. J Endod. 2009;35(2):280–283. https://doi.org/10.1016/j.joen.2008.11.016

32. Fiorillo L., D’Amico C., Meto A., Mehta V., Lo Giudice G., Cervino G. Sodium hypochlorite accidents in endodontic practice: Clinical evidence and state of the art. J Craniofac Surg. 2024;35(7):e636–e645. https://doi.org/10.1097/SCS.0000000000010407

33. Zand V., Lotfi M., Soroush M.H., Abdollahi A.A., Sadeghi M., Mojadadi A. Antibacterial efficacy of different concentrations of sodium hypochlorite gel and solution on enterococcus faecalis biofilm. Iran Endod J. 2016;11(4):315–319. https://doi.org/10.22037/iej.2016.11

34. Azgari E., Özden İ., Gökyar M., Öveçoğlu H.S. Effect of different cleaning methods on surface contamination of unused endodontic files: a scanning electron microscopy analysis. BMC Oral Health. 2025;25(1):1371. https://doi.org/10.1186/s12903-025-06757-x

35. Ertas H., Sagsen B. Comparison of the effect of MTAD and conventional irrigation agents on apical leakage and push-out bond strength of root canal filling. Scanning. 2015;37(6):393–398. https://doi.org/10.1002/sca.21208