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Influence of Sodium Hypochlorite Corrosion on Stainless Steel K-file and Pro Taper Rotary Nickel- Titanium Instrument

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Asaduzzaman Rakib
Asaduzzaman Rakib
Asaduzzaman Rakib
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Mohammad Ali l Asgor Moral at Bangabandhu Sheikh Mujib Medical University
Mohammad Ali l Asgor Moral
Abdul Gafur
Abdul Gafur
Abdul Gafur
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Mst. Dil Afroz Bhuiyan at Bangabandhu Sheikh Mujib Medical University
Mst. Dil Afroz Bhuiyan
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Abstract and Figures

In this work, the corrosion of stainless-steel K-file and pro taper rotary NiTi-file instruments was evaluated and compared about the effects of 5.25% sodium hypochlorite solution. Thirty new Pro Taper NiTi rotary files (D# 20, 25, and 30) and thirty stainless steel K-files (D# 20, 25, and 30) were subjected to a 5-minute immersion in 5.25% NaOCl at 50°C. Every file was put through the corrosion test, which involved recording the open circuit potential (OCP). Corrosion current, corrosion rate, and corrosion potential were all assigned to each file's recording. A potentiated and a standard calomel electrode reference were used to calculate the percentage of open circuit potential (OCP). The frequency of corrosion that may be seen visually was also studied using a scanning electron microscope (SEM). The findings indicated that the corrosion rate for stainless steel has the following mean and standard deviation: The CR of stainless steel pipes with diameters of # 20, # 25, and # 30 is 5.48 0.81 mpy, 5.23 0.84 mpy, and 5.81 1.04 mpy, respectively. The CR of #20, #25, and #30 diameters of Niti files, on the other hand, are 2.61 0.36 mpy, 4.53 0.65 mpy, and 5.38 0.65 mpy, respectively. Statistics showed that the findings between the two files were significant. Additionally, both files had pitting and crevice corrosion, as seen by scanning electron microscopy (SEM) analysis.NiTi files demonstrated a lower rate of corrosion than stainless steel files.
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North American Academic Research.2023,6(10),https://doi.org/10.5281/zenodo.10143858 Monthly Journal by TWASP, USANAAR Home (twasp.info)
Research
Influence of Sodium Hypochlorite Corrosion on
Stainless Steel K-file and Pro Taper Rotary Nickel-
Titanium Instrument
Asaduzzaman Rakib1, Mohammad Ali Asgor Moral1, Abdul Gafur2, Mst. Dil
AfrozBhuiyan1, Mozammal Hossain1*
1Department of Conservative Dentistry & Endodontics, Faculty of dentistry, Bangabandhu Sheikh Mujib Medical
University, Shahbagh, Dhaka-1000, Bangladesh
2Pilot Plant and Processing Development Center, Bangladesh Council for Scientific and Industrial Research (BCSIR)
Dr. Kudrat-E-Khoda Road, Dhanmondi, Dhaka-1205
Abstract: In this work, the corrosion of stainless-steel K-file and pro taper rotary NiTi-file instruments was evaluated
and compared about the effects of 5.25% sodium hypochlorite solution. Thirty new Pro Taper NiTi rotary files (D#
20, 25, and 30) and thirty stainless steel K-files (D# 20, 25, and 30) were subjected to a 5-minute immersion in 5.25%
NaOCl at 50°C. Every file was put through the corrosion test, which involved recording the open circuit potential
(OCP). Corrosion current, corrosion rate, and corrosion potential were all assigned to each file's recording. A
potentiated and a standard calomel electrode reference were used to calculate the percentage of open circuit potential
(OCP). The frequency of corrosion that may be seen visually was also studied using a scanning electron microscope
(SEM). The findings indicated that the corrosion rate for stainless steel has the following mean and standard
deviation: The CR of stainless steel pipes with diameters of # 20, # 25, and # 30 is 5.48 0.81 mpy, 5.23 0.84 mpy, and
5.81 1.04 mpy, respectively. The CR of #20, #25, and #30 diameters of Niti files, on the other hand, are 2.61 0.36 mpy,
4.53 0.65 mpy, and 5.38 0.65 mpy, respectively. Statistics showed that the findings between the two files were
significant. Additionally, both files had pitting and crevice corrosion, as seen by scanning electron microscopy (SEM)
analysis.NiTi files demonstrated a lower rate of corrosion than stainless steel files.
Keywords: Corrosion, Stainless steel file, NiTi file
*Corresponding Author
Accepted: 30 October, 2023; Published: 16 November, 2023
How to cite this article: Asaduzzaman Rakib, Mohammad Ali Asgor Moral, Abdul Gafur, Mst. Dil AfrozBhuiyan, Mozammal Hossain
(2023). Influence of Sodium Hypochlorite Corrosion on Stainless Steel K-file and Pro Taper Rotary Nickel-Titanium Instrument. North
American Academic Research, 6(10), 121-126. doi:https://doi.org/10.5281/zenodo.10143858
Conflicts of Interest: There are no conflicts to declare.
Publisher’s Note:NAAR stays neutral about jurisdictional claims in published maps/image and institutional affiliations.
Copyright:©2023by the authors. Author(s) are fully responsible for the text, figure, data in this manuscript submitted for possible open access publication under the
terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
NAAR,October 2023,Volume 6, Issue 10, 121-126 122 of 126
Introduction
By using chemo-mechanical instruments, root canal therapy seeks to achieve a high level of root canal system
disinfection. By allowing sodium hypochlorite (NaOCl) to enter up to the apical region of the canal and conduct its
bactericidal action,1 by dissolving the organic materials,2 the use of varying diameters of files aids in the development
of a continuous and gradually tapered shape for the root canal.
Traditionally, a stainless-steel K file was used to clean and shape the root canal, but this has many drawbacks, including
a propensity for corrosion and breakage. Because of this, the endodontic field now has access to rotary instruments with
a larger taper and super-elastic and high-strength properties thanks to freshly developed NiTi instruments.3
Additionally, this file achieves good taper with less risk of canal transfer and better preservation of tooth structure than
was feasible with manual files.4 However, when using NiTi Rotary tools in a clinical setting, several variables could
result in an unanticipated fracture.5
Numerous researches also looked at the corrosion of root canal files. When these instruments are disinfected with
NaOCl, 6, 7 or when the solution is used to instrument and irrigate the pulp chamber and root canal, corrosion may
happen.8 NaOCl can also selectively remove alloys from the surface, leading to micro pitting because it is corrosive to
alloys.9,10 These microstructural flaws can cause pockets of stress to build up and cracks to occur, damaging the
instrument's structure.11
The concentration of the NaOCl solution affects how quickly NiTi filings corrode as well. It was discovered that after
coming into contact with 5.25% NaOCl solution, Ni-Ti instruments can begin to corrode within 1–12 hours, and visible
evidence of corrosion can start to appear after 30 minutes of immersion in 5% NaOCl solution. In addition, Oshida et
al.12 discovered a high corrosion rate by heating the 5.25% sodium hypochlorite solution to a temperature of 37°C during
the test. While being used in a clinical setting, nickel-titanium rotary instruments can still be separated without showing
any symptoms or obvious surface changes. NiTi rotary tools' surfaces may corrode or develop surface imperfections as
a result of the irrigation agents used during root canal procedures or the sterilization procedures utilized after root canal
procedures. During clinical use, these flaws and distortions might cause instruments to break.13,14 The issue becomes
serious when the instrument rotates despite having its tip fastened into the root canal or when it is repeatedly subjected
to compression and tensile loads at a level that exceeds metal fatigue while rotating in a curved root canal. Because
different corrosion evaluation techniques were used in the earlier research, the corrosion pattern is still up for debate.
It has been suggested to use a variety of techniques, including atomic force microscopy (AFM) and scanning electron
microscopy (SEM), to investigate the corrosion surface morphology of stainless steel and NiTi instrument surfaces.15,16
To compare and analyze the corrosion susceptibility of stainless steel and NiTi endodontic files submerged in NaOC1,
open circuit potential (OCP) and scanning microscopic examination were used.
NAAR,October 2023,Volume 6, Issue 10, 121-126 123 of 126
Fig. 1: Representative photographs of scanning electron microscopic observation
Research Methodology
This Experimental study was performed in the Department of Conservative Dentistry and Endodontics, Faculty of
Dentistry, Bangabandhu Sheikh Mujib Medical University (BSMMU), Shahbag Dhaka and Bangladesh & PP and PDC
BCSIR, Dhaka Bangladesh during the period from September 2020 to August 2021.
Study sample:
Stainless Steel K file (Sybrone Endo, Made in Mexico) and Pro Taper NiTi Rotary instrument (Dentsply Made in
Switzerland). The inclusion criteria was use of new stainless steel k-file
Study procedure:
5.25% NaOCl was applied to 30 brand-new Pro Taper NiTi rotary files (D # 20, 25 and 30) and 30 stainless steel K-files
(D # 20, 25 and 30) for 5 minutes at 50°C. Every file was put through the corrosion test, which involved recording the
open circuit potential (OCP). Each file's strip chart recording was assigned a stability score. Corrosion current, rate, or
potential are the three types of corrosion. A GAMRY Instrument reference 3000 was used to determine the percentage
of OCP. Scanning electron microscope (SEM) Model: Evo 18 was used to further analyze the frequency of corrosion that
NAAR,October 2023,Volume 6, Issue 10, 121-126 124 of 126
could be seen visually. The maker is Curl Ziess.UK.
Statistical analysis
Data was collected and analyzed by computer based statistical software SPSS version 20. The differences between the
percentage of open circuit potential and visually observed corrosion of stainless steel and NiTi files were assessed by
Chi-square test and a value of p<0.05 will be considered as statistically significant.
Result:
Following immersion in a NaOCl solution, Table 1 displayed the corrosion current, corrosion potential, and corrosion
rate of stainless steel and NiTi files of # 20, 25, and 30. Stainless steel files exhibit higher levels of corrosion current (IC),
rate, and potential than NiTi files, and these differences are statistically significant. In both files, scanning electron
microscopic examination also revealed crevice/pitting corrosion (Figure 1).
Author Contributions: Mozammal Hossain (Supervisor), Mohammad Ali Asgor Moral and Abdul Gafur (prepare the
design of study), Mst. Dil Afroz Bhuiyan (Collect data), Asaduzzaman Rakib (Collect data & create manuscrip)
Approval: All authors have read and agreed to the published version of the manuscript.
Funding: BSMMU & Sellf
Institutional Review Board Statement: Not applicable.
Informed Consent Statement: Not applicable.
Data Availability Statement: Not applicable
Acknowledgments: This study is supported by grants for MS student of Bangabandhu Sheikh Mujib Medical
University
Conflicts of Interest: Authors declare no conflict of interest
References
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rotary instrumentation, 5.25% NaOCl, EDTA, and Ca (OH)2. Journal of Endodontics, 31(5), pp.359-363.
2. Wright, P.P., Scott, S., Kahler, B. and Walsh, L.J., 2020.Organic tissue dissolution in clodronate and etidronate
mixtures with sodium hypochlorite. Journal of endodontics, 46(2), pp.289-294.
3. Yang, H., Sakai, K., Shizuka, H., Kurebayashi, Y., Hayakawa, K. and Nagare, T., 2021. Experimental investiga-
tion of the effects of super-elasticity on the machinability of NiTi alloys. The International Journal of Advanced
Manufacturing Technology, 115(1), pp.581-593.
4. Baruah, K., Augustine, V., Tiwari, R.V., Singh, S., Dixit, H. and Thmpala, V.K., 2017.Advances in rotary endo-
dontics-a review. Journal of Advanced Medical and Dental Sciences Research, 5(7), p.17.
5. Plotino, G., Grande, N.M., Melo, M.C., Bahia, M.G., Testarelli, L. and Gambarini, G., 2010.Cyclic fatigue of NiTi
rotary instruments in a simulated apical abrupt curvature. International Endodontic Journal, 43(3), pp.226-230.
6. Berutti, E., Angelini, E., Rigolone, M., Migliaretti, G. and Pasqualini, D., 2006. Influence of sodium hypochlorite
on fracture properties and corrosion of ProTaper Rotary instruments. International endodontic journal, 39(9),
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7. Sonntag, D. and Peters, O.A., 2007.Effect of prion decontamination protocols on nickel-titanium rotary sur-
faces. Journal of endodontics, 33(4), pp.442-446.
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8. Neelakantan, P., Khan, K., Ng, G.P.H., Yip, C.Y., Zhang, C. and Cheung, G.S.P., 2018. Does the orifice-directed
dentin conservation access design debride pulp chamber and mesial root canal systems of mandibular molars
similar to a traditional access design?. Journal of endodontics, 44(2), pp.274-279.
9. Sağlam, B.C., Koçak, S., Koçak, M.M. and Topuz, Ö., 2012. Effects of irrigation solutions on the surface of ProTa-
per instruments: A microscopy study. Microscopy research and technique, 75(11), pp.1534-1538
10. Restrepo-Restrepo, F.A., Holguín-Vásquez, V.A., Cañas-Jiménez, S.J., Villa-Machado, P.A., Ochoa-Soto, S.,
Ossa-Orozco, C.P. and Tobón-Arroyave, S.I., 2021. Microstructural, microchemical, and mechanical changes
associated with the clinical reuse of two nickel–titanium endodontic instruments. Dental Research Journal, 18(1),
p.48.
11. Pedulla, E., Grande, N.M., Plotino, G., Pappalardo, A. and Rapisarda, E., 2011.Cyclic fatigue resistance of three
different nickel-titanium instruments after immersion in sodium hypochlorite. Journal of endodontics, 37(8),
pp.1139-1142.
12. Oshida, Y. and Tominaga, T., 2020.Corrosion and oxidation.In Nickel-Titanium Materials. pp. 297-388.
13. Parashos, P. and Messer, H.H., 2006. Rotary NiTi instrument fracture and its consequences. Journal of endodon-
tics, 32(11), pp.1031-1043.
14. Coelho, M.S., de Azevêdo Rios, M. and da SilveiraBueno, C.E., 2018. Separation of nickel-titanium rotary and
reciprocating instruments: a mini-review of clinical studies. The open dentistry journal, 12, p.864.
15. Bonaccorso, A., Tripi, T.R., Rondelli, G., Condorelli, G.G., Cantatore, G. and Schäfer, E., 2008. Pitting corrosion
resistance of nickel–titanium rotary instruments with different surface treatments in seventeen percent eth-
ylenediaminetetraacetic acid and sodium chloride solutions. Journal of endodontics, 34(2), pp.208-211.
16. Toloei, A., Guo, M. and Rotermund, H.H., 2015.The effect of surface morphology on corrosion performance of
SS 316 LVM biomedical devices. Journal of Materials Engineering and Performance, 24(10), pp.3726-3736.
Mozammal Hossain
PhD, Japan, Professor
Department of Conservative Dentistry & Endodontics, Faculty of dentistry
Bangabandhu Sheikh Mujib Medical University, Shahbagh, Dhaka-1000, Bangladesh.
NAAR,October 2023,Volume 6, Issue 10, 121-126 126 of 126
Asaduzzaman Rakib
MS, (Conservative Dentistry & Endodontics), BDS (DU), Medical Officer (BSMMU)
Department of Conservative Dentistry & Endodontics,Faculty of dentistry
Bangabandhu Sheikh Mujib Medical University, Shahbagh, Dhaka-1000, Bangladesh.
ResearchGate has not been able to resolve any citations for this publication.
Microstructural, microchemical, and mechanical changes associated with the clinical reuse of two nickel–titanium endodontic instruments
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ADVANCES IN ROTARY ENDODONTICS-A REVIEW
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Organic Tissue Dissolution in Clodronate and Etidronate Mixtures with Sodium Hypochlorite
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Introduction: Mixtures of clodronate with sodium hypochlorite (NaOCl) better maintain free available chlorine (FAC) than etidronate-hypochlorite mixtures. This research aimed to compare organic tissue dissolution and residual FAC between clodronate and etidronate mixtures. Additionally, clodronate-hypochlorite mixtures lose no FAC over several hours. The second aim was to examine how well such mixtures dissolve organic material 6 hours from mixing. Methods: Soon after mixing, porcine palatal mucosa samples were added to 32°C solutions containing 0.26 mol/L clodronate and 5% NaOCl (0.26 mol/L-5% NaOCl), 0.26 mol/L etidronate-5% NaOCl, 5% NaOCl, 0.26 mol/L clodronate, 0.26 mol/L etidronate, or phosphate-buffered saline. Weights and FAC, where applicable, were recorded initially and at 15 minutes. FAC was measured by iodometric titration. Secondly, 6 hours after mixing, mucosa was added to 0.26 mol/L clodronate-2.5% NaOCl, 2.5% NaOCl, 0.52 mol/L clodronate-5% NaOCl, 5% NaOCl, or phosphate-buffered saline. Sample weights at 0, 5, 10, and 15 minutes were recorded. Analysis of variance was used for statistical analyses (α < .05). Results: Soon after mixing, 0.26 mol/L clodronate-5% NaOCl dissolved mucosa as well as 5% NaOCl and better than 0.26 mol/L etidronate-5% NaOCl compared with which it retained more FAC. At 6 hours after mixing, 0.26 mol/L clodronate-2.5% NaOCl dissolved organic material as well as 2.5% NaOCl. However, 0.52 mol/L clodronate-5% NaOCl dissolved less mucosa than 5% NaOCl. Conclusions: Soon after mixing, clodronate mixtures better dissolve organic material than etidronate mixtures and have higher residual FAC. Six hours from mixing, 0.26 mol/L clodronate-2.5% NaOCl mixtures dissolve organic material similarly to controls.
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Does the Orifice-directed Dentin Conservation Access Design Debride Pulp Chamber and Mesial Root Canal Systems of Mandibular Molars Similar to a Traditional Access Design?
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Article
  • Aug 2015
In this study, in order to investigate the relationship between surface roughness and the corrosion resistance of the SS 316 LVM wires, samples have been prepared with different surface roughness by using different grits of SiC papers. In order to simulate the environment of implanted biomedical devices, a three-electrode electrochemical cell with 0.9% (by mass) NaCl solution has been used to test the corrosion resistance of the samples by potentiodynamic method and anodic polarization tests. SEM, EDS, and XPS have been performed to analyze the surfaces appearance and chemical elements on the surface before and after the corrosion. AFM was also used to get 3D images of the surface and to show the change in roughness of the samples after corrosion testing. Background-subtracted contrast-enhanced microscopy has been performed in situ to detect the pitting process happening on the surface of stainless steel samples. It was concluded that a relatively smoother surface can result in higher corrosion resistance and larger potential of stable pitting, whereas a rougher surface can easily go into stable pitting with lower pitting potentials. Rougher surfaces also showed a shorter time for the formation of stable pits. Microscopy observations illustrated more corrosion on rougher surfaces, and EDS showed more chloride ion remained on these surfaces.
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Effects of irrigation solutions on the surface of ProTaper instruments: a microscopy study
Article
  • Nov 2012
  • MICROSC RES TECHNIQ
The aim of this study was to evaluate the effects of sodium hypochlorite (NaOCl), chlorhexidine digluconate (CHX), and mixture of tetracycline, citric acid, and detergent (MTAD) solutions on the surfaces of nickel titanium (NiTi) rotary files with scanning electron microscopy (SEM) and atomic force microscopy (AFM). Irrigation solutions including 2.5% NaOCl, 5% NaOCl, 2% CHX, and MTAD were used. Four new ProTaper rotary NiTi files (F3) were immersed in each four irrigation solutions for 10 min, separately. One untreated NiTi file was used as a control specimen. The surface analysis was performed with SEM and AFM. The surface analysis in AFM was performed on 12 different regions located between first and second millimeters from the tip. SEM images were taken with different magnifications. No surface alteration was recorded under SEM evaluation. AFM revealed that the root mean square (RMS) values of all treated specimens were statistically higher than the control sample (P < 0.05). The sample which was treated with CHX showed lowest RMS values in test groups. All tested solutions caused surface alterations. CHX demonstrated limited surface alterations when compared to the other tested solutions. Microsc. Res. Tech. © 2012 Wiley Periodicals, Inc.
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