Effect of Cellular Radiation on Nickel Release from Fixed Orthodontic wires: An In Vitro Study

Effect of Cellular Radiation on Nickel Release from Fixed Orthodontic wires: An In Vitro Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Effect of Cellular Radiation on Nickel Release from Fixed Orthodontic wires: An In Vitro Study Gargi Sivadasan, Arun S Urala, Adith Venugopal, Kalyana Chakravarthy Pentapati, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9343210/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Around 90 percent of the global population are constantly exposed to the electromagnetic radiation from handheld mobile phones. Due to the proximity of mobile phones to the oral cavity during the conversation period, the radiation emitted might influence the environment of the oral cavity. Few studies showed there was a time-dependent increase in nickel release among patients undergoing in orthodontic treatment who were exposed to cellular radiation. The increase in nickel was attributed to increased salivary flow due to mobile phone radiation. This in vitro study was carried out to analyse if nickel released is due to a direct effect of mobile radiation rather than due to increased flow of the saliva. This invitro study was planned with four groups containing five pairs of 18 x 25 Nickel titanium (NiTi) and Stainless steel (SS) orthodontic wires. These wires were immersed in 40 ml of artificial saliva. The experimental group (NiTi and SS) was exposed to cellular radiation (900 Hz) with help of an GTEM cell. The nickel release was assessed the 1st, 7th, 14th, 21st, and the 28th day using atomic mass Spectrometry. The NiTi Orthodontic wires exposed to cellular radiation showed significantly higher mean Nickel concentration on day 7th and 28th day (P = 0.016 and 0.028) when compared to NiTi Orthodontic wires unexposed to cellular radiation. However, on day 21, NiTi Orthodontic wires unexposed to cellular radiation showed higher mean Nickel concentration than those exposed to cellular radiation (P = 0.009). The SS Orthodontic wires unexposed to cellular radiation showed significantly higher mean Nickel concentration on day 14th and 21st day (P = 0.028 and 0.028) when compared to SS Orthodontic wires exposed to cellular radiation. The findings of this study showed that increased Nickel concentrations in artificial saliva among NiTi orthodontic wires exposed to cellular radiation. Health sciences/Health care Physical sciences/Materials science Health sciences/Medical research Arch wires Cell Phones Electromagnetic Radiation Mass Spectrometry Nickel Titanium Stainless Steel Figures Figure 1 Figure 2 Figure 3 Figure 4 INTRODUCTION Communication has existed in various forms and has changed significantly over time. Cell phones have evolved from their original purposes as business tools and are now primarily used as personal communication tool¹. Signals from cellular phones are transmitted in the form of radio waves, which form a part of the non-ionising region of the electromagnetic spectrum. Radio communication in mobile phones uses microwave frequencies of 900 or 1800 MHz, where voice information is transmitted through small variations in the wave’s frequency². A handset in use also produces a low-frequency magnetic field. Notably, Time Division Multiple Access (TDMA) based mobile phones emit pulses at about 217 Hz during active calls and around 8.34 Hz when in standby mode². Various in vitro and animal studies have shown that exposure to electromagnetic radiation can cause DNA damage³ − ⁵. The International Agency for Research on Cancer (IARC) has classified cellular radiation as possibly carcinogenic to humans. The other adverse health effects of cellular radiation have also been under constant investigation. The oral cavity has considerable exposure to cellular radiation when one considers the proximity of the same. Studies carried out on functional and volumetric changes in salivary flow⁶, histopathological evaluation⁷ , ⁸ of the parotid gland cells to electromagnetic radiation have yielded positive results, implying the potential risk cellular radiation. Fixed orthodontic treatment consists of a wide range of metal components that are fabricated with nickel-containing alloys. These intra orally placed wires or components are exposed continuously to the oral cavity ⁹, resulting in the release of metals. Saliva, environmental factors (mouth breathing), oral micro flora, manufacturing process⁹ can also influence the corrosive process and subsequent metal release. Increase in corrosive nature of the components can result in increased friction, inability to express torque or super elastic properties¹⁰. The major metallic ions that leach out of the orthodontic appliances are Fe, Cr, and Ni. All the three elements potentially have adverse effects. But Ni and Cr with reported potential for producing allergic, toxic, carcinogenic effects have received the most attention⁹. Nickel has found to be carcinogenic in both in its free form as well as in complexes (chloride and sulphide). Nickel is said to have potential to induce oxidative stress through mechanisms such as induction of Cap43 (hypoxia-regulated gene), induction of HIF (Hypoxia Inducible Factors), elevation of lipid peroxidation, release of lactate dehydrogenase, increased acetaldehyde formation, histone hydrolysis and inhibition of histone H4 acetylation¹⁰. It is also hypothesized that nickel can cause potential DNA damage through the promotion of DNA strand scission (single strand breaks), induction of p53 and K-Ras alterations, inhibition of DNA repair enzymes, increase in DNA methylation, induction of silent gene expression by chromatin condensation, incorporation of critical genes into heterochromatin, and methylation of DNA resulting in silencing genetic activity necessary for the maintenance of normal cellular functions.¹⁰ Being potent allergens or haptens, nickel ions can penetrate epithelial cells and produce various cytokines or chemokines that can result in activation of antigen presenting cells and T cells. Delayed hypersensitivity reaction after 48–72 hours is seen following exposure.¹¹ A recent study done by Saghiri et al.¹², showed that in orthodontic patients with fixed appliances, cell phone radiation can influence the concentration of nickel in saliva in a time dependant manner. The increased presence of nickel ions was attributed to the increased flow of saliva due to radiation exposure from the cellular phones. With an increasing percentage of cell phone subscribers among the population and with regards adverse nature of the nickel ions, further research seems to be inevitable. Within this background, it could be implied that nickel ions leach into the oral cavity and may have potential implications for the patients undergoing orthodontic treatment. The present in vitro study investigated relationship between mobile phone radiation and the release of nickel ions among two groups of wires. The null hypothesis was that there would no difference in the nickel ions release with or without cellular radiation exposure. METHODS Ethical committee approval was obtained from the institutional ethical committee (IEC no.654/2015) before the commencement of the study. The study included four groups consisting of five pairs of 0.018 x 0.025 inch Orthodontic arch wires immersed in artificial saliva. They were divided into four groups (Table 1 ). Each group had five pairs of Orthodontic wires. The length of the arch wire 13 was determined with the help of an ideal typodont set, measured distally from the second molar tube of the right quadrant to the second molar tube on the left quadrant. The upper arch wire measured about 12.3 cm and the lower arch wire measured about 11.8 cm in length. The wires were employed in their “as received” condition after being cut to their specific lengths. Table 1 Description of four study groups Group I (Control Group) 0.018 x 0.025 NiTi arch wires; not exposed to cellular radiation Group II (Control Group) 0.018x0.025 Stainless steel arch wires; not exposed to cellular radiation Group III (Experimental Group) 0.018x0.025 NiTi arch wires which were exposed to cellular radiation Group IV (Experimental Group) 0.018x0.025 Stainless Steel arch wires which were exposed to cellular radiation Preparation of artificial saliva was carried out which is specific in nature to study the corrosive nature of dental materials. 14 Table 2 mention the ingredients used in preparation of artificial saliva. Table 2 Composition of Artificial Saliva Ingredient Quantity(mmol/l) Na 15.33 K 5.37 Ca 5.40 Mg 0.02 Cl 23.02 PO 4 4.23 Urea 16.65 Na 2 S 15.34 P 2 O 7 0.01 The prepared artificial saliva (pH of 5.5–6.0) was stored under refrigeration till the time of usage. Samples were housed in Glass petri dishes of dimensions 18x15 mm (Borosil, India) which facilitated the passage of radiation as well as which could hold the arch wires without inducing deformation. Both control and experimental group samples were immersed in 40 ml of artificial saliva and were stored at 37 degree Celsius. The petri dish was always covered with the help of a lid except during the time of radiation exposure to prevent evaporation of the immersion media (Fig. 1 ). The experimental groups were exposed to cellular radiation (900 Hertz) for a period of one hour everyday with help of a Gigahertz Transverse Electro Magnetic (GTEM) cell (Figs. 2 and 3 ) which was fabricated based on the specifications given by Clemens 15 . It is an expanded transmission line which operates in the Transverse Electro Magnetic (TEM mode), with a characteristic impedance of 50Ω to avoid reflections. It is a pyramidal-shaped, tapered, dual-terminated section with its outer cell measuring about 220 cm (L) X 120 cm (B) X 80 cm (H), which provides a controllable and shielded environment for studying the effect of electromagnetic radiation in cellular and animal models. The EMF radiation source consists of a signal generator. It operates at a frequency range of 40MHz to 4.4GHz, a direction coupler and power meter (-30 to + 20dbm). The EMF chamber is equipped with RF absorbers. These further reduce the possibility of any reflections. On days 1, 7, 14, 21, and 28, the entire 40 ml of artificial saliva was agitated prior to removal. The samples were analysed within a period of half an hour with the help of atomic absorption spectrometry (AAS ICE 3300, Thermo Fisher Scientific, USA – Fig. 4 ). It is an analytical technique that measures the concentrations of elements present in a solution. This technique works on the principle of specific wavelength absorption by an element. Replacement with a freshly prepared artificial saliva was carried out (on days 1,7,14, and 21) to avoid saturation of the ions in the medium as suggested by previous studies 13 . AAS has the following three components: a light source, a sample cell to produce gaseous atoms, and a means to measure the specific light absorbed. There are several lamps present, which are held on a rotating turret specific to each element. With the help of a monochromator, a specific wavelength of light known as the spectral line is chosen, which is absorbed by the sample. A photomultiplier tube helps in producing an electrical signal that is proportional to the intensity of light absorbed. The sample, when atomised, is converted into ground state free atoms in the vapour state after which a beam of electromagnetic radiation is passed through the vaporised sample. The greater the number of atoms of a particular element, the greater the amount of radiation absorbed. The concentrations of the known samples are first tested, after which a calibration curve is constructed. The amount of standard absorbed is then used to calculate the concentration of the element in the unknown sample. Atomisation of the study samples was carried out by means of aspiration of the solution onto the flame. This process converts the samples into their free atoms; irrespective of their initial state, the chemical form of the element is not of much significance. Working Standard solutions of nickel with a concentration of 1,3,5,7 mg/L were tested and calibrated prior to the testing of samples. Each study sample was aspirated and then tested thrice, after which the mean value was recorded. About 100 study samples in total were analysed in a period of one month. STATISTICAL ANALYSIS All the analysis was done using SPSS version 26. A p-value of < 0.05 was considered statistically significant. Normality of the data was assessed using Shapiro Wilks test. Comparison of mean values between the groups was done using Mann-Whitney U test. RESULTS The NiTi Orthodontic wires exposed to cellular radiation showed significantly higher mean Nickel concentration on day 7th and 28th day (P = 0.016 and 0.028) when compared to NiTi Orthodontic wires unexposed to cellular radiation. However, on day 21, NiTi Orthodontic wires unexposed to cellular radiation showed higher mean Nickel concentration than those exposed to cellular radiation (P = 0.009). The SS Orthodontic wires unexposed to cellular radiation showed significantly higher mean Nickel concentration on day 14th and 21st day (P = 0.028 and 0.028) when compared to SS Orthodontic wires exposed to cellular radiation (Table 3 ) Table 3 Mean and Standard deviation for the rates of Nickel release in mg/dl at days 1,7,14,21 and 28 Control Experiment P-value Mean SD Mean SD NiTi Day 1 .0280 .0093 .0401 .0104 0.076 NiTi Day 7 .0116 .0028 .0186 .0039 0.016 NiTi Day 14 .0154 .0072 .0187 .0027 0.347 NiTi Day 21 .0290 .0124 .0030 .0016 0.009 NiTi Day 28 .0064 .0023 .0241 .0297 0.028 SS Day 1 .0411 .0095 .0525 .0088 0.075 SS Day 7 .0166 .0015 .0211 .0099 0.600 SS Day 14 .0136 .0022 .0064 .0042 0.028 SS Day 21 .0104 .0080 .0032 .0012 0.028 SS Day 28 .0109 .0031 .0136 .0012 0.117 DISCUSSION Orthodontic treatment involves the usage of fixed appliances which consists of arch wires, bands, brackets and other auxiliaries that are fabricated with nickel containing alloys, which when placed in the oral cavity with a constantly reactive and changing environment can lead to corrosion of the metal components. 9 Placement of any material in the body creates an interface that is a site of many dynamic interactions between the body and the material or vice versa. The dynamics in these interactions will determine both the biological response to the material as well as the ability of the material to resist or survive corrosion in the body. Local and systematic effects produced by the material are modulated by substances that are released from it and the biological response to the same. 16 Various in vitro and in vivo studies have investigated the release of metal ions such as nickel, chromium, iron, molybdenum from orthodontic appliances. Nickel is said to be a strong immunologic sensitizer, cytotoxic and also mutagenic in nature and hence has been a subject of concern to many researchers. 16 Many individuals worldwide are exposed to radiofrequency waves from cellular phones and other personal communication devices whose effect might be potentially detrimental to health. 17 During the period of usage, cellular phone lies near the head and the oral cavity. The presence of metallic components in the oral cavity of an orthodontic patient, compel the need to study the effect of cellular radiation on the same. An in vivo study carried out by Saghiri et al 12 showed that exposure to Radio Frequency Electro Magnetic Radiation emitted by mobile phones can result in time dependant increase in the nickel released from the fixed appliances. They attributed the increased nickel release to the greater flow rate of saliva and lower concentration of components in saliva which in turn resulted in more nickel released from fixed appliances into saliva. According to the study, heat which is generated by the mobile phones can influence the properties, flow rate, pH, of saliva which can influence the corrosion rate of the orthodontic appliance. If there would be an increase in the flow rate of saliva due to cellular radiation, could a diluting effect on the concentration of corrosion products be anticipated rather than an increase of the same? Is there a possibility that the cellular radiation might have a direct effect on the increased rate of nickel release? Thus, this in vitro study was carried out to quantify nickel release from commonly used orthodontic wires exposed to cellular radiation. The findings of the present study indicate that cellular radiation can produce a statistical significant increase in the concentration of nickel ions. Higher mean concentration of nickel was attained on the 1st and on the 21st day in the NiTi control group and was about 0.028 mg/dl and 0.029 mg/dl respectively. The highest concentration of nickel in the NiTi experimental group was about 0.04 mg/dl attained on the 1st day. The highest concentration of nickel in the SS experimental group was about 0.050 mg/dl attained on the 1st day as compared to 0.041 in the SS control group. Intergroup comparison between SS control (Group 2) and SS experimental (Group 4) shows a statistically significant increase in the concentration of nickel on days 14,21. The increase of nickel concentration was by about 53.3%,69% respectively in the experimental group. From the above findings, one can note that exponential increase to nickel concentration resulted from exposure to radiation which was more evident in Group 3 than in Group 4 where the increase was observed only on days 14 and 21. The decrease in nickel release noted in the experimental groups at day 21 may be explained by the enhanced rate of corrosion in the early stages, leading to a depletion of nickel ions from the surface. This may have been followed by a temporary repassivation of the alloy surface. In contrast, a delay in corrosion was noted in the control groups, leading to a higher release of nickel ions at this time point. The increase noted in nickel release from day 28 may be attributed to a destabilization effect of the passive film because of prolonged irradiation which can be called as Non linear, time dependent corrosion phenomenon. We can categorize this dynamic process in to three phases – early surface activation Day 1 to 7 (disruption of the passive oxide layer which releases the nickel into the saliva – increase burst of nickel due to irradiation, surface depletion stage – where surface nickel has leached out very less active nickel available which may result in the temporary reduction in the corrosion rate. Obviously in the controlled group there is delayed corrosion going on so at this point the control group shows more than the experimental group at Day 21. After this phase 3 – Destabilization stage (secondary corrosion – Day 28) continuous irradiation in the experimental group has caused destabilization of the repassivated layer has induced microstructural damage. This may be the reason we see spike in the Experimental group on day 28. Statistically significant results were obtained in this in vitro study, which was not affected by the increased flow, diluting effect of the macromolecules present or due to an alteration of the pH of the saliva produced by the salivary gland after exposure to cellular radiation. Could the increase in the concentration of nickel be attributed to a direct effect of cellular radiation on the arch wire samples? Cellular radiation is nonionizing, electromagnetic in nature 2 . The resultant radiation can only result in excitation of the matter when it passes through. Could this excitation of atoms result in increase in the temperature of the matter resulting in increased corrosion of the same? Dielectric effect 18 of a material result when exposed to microwave and radiofrequency waves, in which heating occurs due to interaction of electric and magnetic fields with the material. Induced diploes can result which can lead to a rise in temperature. But the dielectric effect depends upon the dielectric properties of the material, material volume, and penetration depth of the waves used. Nickel nano fillers 19 have been used to increase the dielectric properties of composites in various engineering applications. Can the positive findings of the study be attributed to a possible dielectric effect? An increase in temperature affects the resistance to localized corrosion by reducing the ability of the material to repassivate 12 , thus contributing to increased nickel release in the arch wire samples exposed to radiation in this study In a study done by Barrett et al 13 , the overall release pattern of nickel was similar for both Nickel titanium and Stainless-steel appliances. A peak in nickel concentration was seen at day 7 followed by steady decline. Nickel release was greater in the stainless-steel appliances on day 14th (statistically significant).The average release of nickel during the four week period averaged 13.05 µg/day (single arch). Shearer and Park 20 reported that the corrosion of orthodontic appliances reached plateau after a period of 6 days and did not increase after that. In this present study, the mean concentration of NiTi control (Group 1) and SS control (Group 2) peaked on the 1st day and declined after that except for day 21 in the NiTi Control (Group 1).Could the difference in the release kinetics be attributed to manufacturing process which could also play a role according to Eliades et al. Another interesting finding of this study is that average release during the period of one month were similar in all the four groups (0.017 mg/dl, 0.018 mg/dl, 0.016 mg/dl,0.019 mg/dl respectively). But there existed significant difference of the means during specific time intervals between the control and the experimental group. Could the exposure to cellular radiation cause an increased depletion of nickel ions from the surface of the arch wires during those time intervals? The dietary allowance of nickel is about 200–300 µg per day 13 . Though the levels obtained during various in vitro investigations are lower than the above, the resultant might be sufficient to produce biological effects in the oral mucosa. 21 Cellular radiation is said to be genotoxic, cyotoxic and co -carcionogenic in nature 17 . According to the results of this study, cellular radiation can cause increased release of nickel ions from orthodontic arch wires in a direct manner. Emphasis must be given to the findings of the study that cellular radiation can potentially present with a co - carcinogenic effect on the oral cavity in conjunction with increased release of nickel ions. CONCLUSION The effect of cellular radiation on Nickel release was evaluated in both Nickel Titanium and Stainless-steel arch wires. Mobile phone radiation can have a direct effect on the release of nickel ions from orthodontic arch wires. There seems to be an exponential increase in the concentration or the release of nickel to mobile phone radiation Declarations Funding: No funding was obtained for this study Acknowledgements: None Data Availability: Included in the paper or Supplementary Information (for raw data, not summary data such as means and variances). All data supporting the findings of this study are available within the paper and its Supplementary Information. Author Contribution G S: Conceptualization, Data Curation, Formal Analysis, Methodology; ASU: Conceptualization, Project Administration;A V: Writing – Review & Editing; KCP: Results ; KG: Supervision, Resources; ATP: Writing – Review & Editing; S D: Original Draft Preparation, Writing – Review & Editing. Acknowledgement None Data Availability Included in the paper or Supplementary Information (for raw data, not summary data such as means and variances).All data supporting the findings of this study are available within the paper and its Supplementary Information. References Aoki, K. & Downes, E. J. An analysis of young people’s use of and attitudes toward cell phones. Telematics Inform. 20 (4), 349–364 (2003). Hyland, G. J. Physics and biology of mobile telephony. Lancet 356 (9244), 1833–1836 (2000). Lai, H. & Singh, N. P. Acute low-intensity microwave exposure increases DNA single‐strand breaks in rat brain cells. Bioelectromagnetics 16 (3), 207–210 (1995). Lai, H. N. Single-and double-strand DNA breaks in rat brain cells after acute exposure to radiofrequency electromagnetic radiation. Int. J. Radiat. Biol. 69 (4), 513–521 (1996). Lourencini da Silva, R., Albano, F., Lopes dos Santos, L. R., Tavares, A. D. Jr & Felzenszwalb, I. The effect of electromagnetic field exposure on the formation of DNA lesions. Redox Rep. 5 (5), 299–301 (2000). Bhargava, S., Motwani, M. B. & Patni, V. M. Effect of handheld mobile phone use on parotid gland salivary flow rate and volume. Oral surgery, oral medicine, oral pathology and oral radiology. ; 114 (2):200–206. (2012). Daroit, N. B., Visioli, F., Magnusson, A. S., Vieira, G. R. & Rados, P. V. Cell phone radiation effects on cytogenetic abnormalities of oral mucosal cells. Brazilian oral Res. 29 (1), 1–8 (2015). Souza, L. D., Cerqueira, E. D. & Meireles, J. R. Assessment of nuclear abnormalities in exfoliated cells from the oral epithelium of mobile phone users. Electromagn. Biol. Med. 33 (2), 98–102 (2014). Eliades, T. & Athanasiou, A. E. In vivo aging of orthodontic alloys: implications for corrosion potential, nickel release, and biocompatibility. Angle Orthod. 72 (3), 222–237 (2002). Eliades, T. & Bourauel, C. Intraoral aging of orthodontic materials: the picture we miss and its clinical relevance. Am. J. Orthod. Dentofac. Orthop. 127 (4), 403–412 (2005). Saito, M. et al. Molecular mechanisms of nickel allergy. Int. J. Mol. Sci. 17 (2), 202 (2016). Saghiri, M. A., Orangi, J., Asatourian, A., Mehriar, P. & Sheibani, N. Effect of mobile phone use on metal ion release from fixed orthodontic appliances. Am. J. Orthod. Dentofac. Orthop. 147 (6), 719–724 (2015). Barrett, R. D., Bishara, S. E. & Quinn, J. K. Biodegradation of orthodontic appliances. Part I. Biodegradation of nickel and chromium in vitro. Am. J. Orthod. Dentofac. Orthop. 103 (1), 8–14 (1993). Leung, V. W. H. & Darvell, B. W. Artificial salivas for in vivo studies of dental materials. J. Dent. 25 (6), 475–484 (1997). Icheln, C. The construction and application of a GTEM cell. HUT Hmaburg Nov 1. (1995). Anusavice, K. J. & Kenneth, J. Phillips’ science of dental materials (Mo: Saunders., 2003). Behari, J. Biological responses of mobile phone frequency exposure. Indian J. Exp. Biol. 48 (10), 959–981 (2010). Roussy, G. & Pearce, J. A. Foundations and industrial applications of microwave and radio frequency fields: physical and chemical processes. (No Title). Jun 6. (1995). Jamal, E. M., Mohanan, P., Joy, P. A., Kurian, P. & Anantharaman, M. R. Effect of nickel nanofillers on the dielectric and magnetic properties of composites based on rubber in the X-band. Appl. Phys. A . 97 (1), 157–165 (2009). Park, H. Y. & Shearer, T. R. In vitro release of nickel and chromium from simulated orthodontic appliances. Am. J. Orthod. 84 (2), 156–159 (1983). Natarajan, M., Padmanabhan, S., Chitharanjan, A. & Narasimhan, M. Evaluation of the genotoxic effects of fixed appliances on oral mucosal cells and the relationship to nickel and chromium concentrations: an in-vivo study. Am. J. Orthod. Dentofac. Orthop. 140 (3), 383–388 (2011). Additional Declarations No competing interests reported. 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Siddalingappa","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA5klEQVRIiWNgGAWjYDCCwxBKDkQcYGCwAFIJxGkxhmqRIELLAQiV2AChidDCd5zHTOIHQ1362vazBw8X1Egw8LPnGODVInmYx0yyh+Fw7rYzeQmHZxyTYJDseYNfi8FhtjQJHoYDudsO5Bgc5mGTYDC4QcAWkBbJP0CHmZ1/A9TyT4LBnrAW5mPSPAzMCWZAlYd524C2SBD0C/NhaxmDw4bbbgBtmdknwSNx5lkBXi185w823nxTUSdvdj7H+HPBNxs5/vbkDXi1AAEL0DEQFjMQ8xBSDlb4Ac4iRvkoGAWjYBSMPAAAmVdFBYp/aVEAAAAASUVORK5CYII=","orcid":"","institution":"Manipal College of Dental Sciences, Manipal Academy of Higher Education","correspondingAuthor":true,"prefix":"","firstName":"Divya","middleName":"","lastName":"Siddalingappa","suffix":""}],"badges":[],"createdAt":"2026-04-07 10:10:29","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9343210/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9343210/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":108182005,"identity":"d944c193-63f1-48fb-9924-e6a10cfb6fad","added_by":"auto","created_at":"2026-04-30 08:59:04","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":715373,"visible":true,"origin":"","legend":"\u003cp\u003ePlacement of the study samples in petri dishes\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-9343210/v1/428b1668f579395bb9fc1502.jpeg"},{"id":108072532,"identity":"9e463b23-3caa-4a75-9809-516b3e71ad2d","added_by":"auto","created_at":"2026-04-29 06:14:09","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":511771,"visible":true,"origin":"","legend":"\u003cp\u003eGTEM cell\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-9343210/v1/382568a1be38044390cbd34a.jpeg"},{"id":108182624,"identity":"e8c16f34-aaa7-4742-a838-bd4ca50dc741","added_by":"auto","created_at":"2026-04-30 08:59:28","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":499946,"visible":true,"origin":"","legend":"\u003cp\u003ePlacement of the study samples for radiation exposure inside the GTEM cell\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-9343210/v1/4e29380e266a7643263c49de.jpeg"},{"id":108072534,"identity":"f8f91b09-32df-46b8-b001-d2fe9d5f7f1c","added_by":"auto","created_at":"2026-04-29 06:14:09","extension":"jpeg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":138563,"visible":true,"origin":"","legend":"\u003cp\u003eAtomic Absorption Spectrometry\u003c/p\u003e","description":"","filename":"floatimage4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-9343210/v1/533050c0aba2f68d7f2d5751.jpeg"},{"id":108490831,"identity":"2363c5ac-fade-4ba3-bcb6-d02dc4ca73f4","added_by":"auto","created_at":"2026-05-05 09:49:03","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2128598,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9343210/v1/cc6d949d-2bca-488f-9af1-3a858972867d.pdf"},{"id":108072530,"identity":"ecfd0552-a5e9-4117-b590-31d0c706f9cc","added_by":"auto","created_at":"2026-04-29 06:14:09","extension":"xlsx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":6270,"visible":true,"origin":"","legend":"","description":"","filename":"14426.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-9343210/v1/c516312a8dbb4858cc637ff4.xlsx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Effect of Cellular Radiation on Nickel Release from Fixed Orthodontic wires: An In Vitro Study","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eCommunication has existed in various forms and has changed significantly over time. Cell phones have evolved from their original purposes as business tools and are now primarily used as personal communication tool\u0026sup1;. Signals from cellular phones are transmitted in the form of radio waves, which form a part of the non-ionising region of the electromagnetic spectrum.\u003c/p\u003e \u003cp\u003eRadio communication in mobile phones uses microwave frequencies of 900 or 1800 MHz, where voice information is transmitted through small variations in the wave\u0026rsquo;s frequency\u0026sup2;. A handset in use also produces a low-frequency magnetic field. Notably, Time Division Multiple Access (TDMA) based mobile phones emit pulses at about 217 Hz during active calls and around 8.34 Hz when in standby mode\u0026sup2;.\u003c/p\u003e \u003cp\u003eVarious in vitro and animal studies have shown that exposure to electromagnetic radiation can cause DNA damage\u0026sup3;\u003csup\u003e\u0026minus;\u003c/sup\u003e⁵. The International Agency for Research on Cancer (IARC) has classified cellular radiation as possibly carcinogenic to humans. The other adverse health effects of cellular radiation have also been under constant investigation.\u003c/p\u003e \u003cp\u003eThe oral cavity has considerable exposure to cellular radiation when one considers the proximity of the same. Studies carried out on functional and volumetric changes in salivary flow⁶, histopathological evaluation⁷\u003csup\u003e,\u003c/sup\u003e⁸ of the parotid gland cells to electromagnetic radiation have yielded positive results, implying the potential risk cellular radiation.\u003c/p\u003e \u003cp\u003eFixed orthodontic treatment consists of a wide range of metal components that are fabricated with nickel-containing alloys. These intra orally placed wires or components are exposed continuously to the oral cavity ⁹, resulting in the release of metals. Saliva, environmental factors (mouth breathing), oral micro flora, manufacturing process⁹ can also influence the corrosive process and subsequent metal release. Increase in corrosive nature of the components can result in increased friction, inability to express torque or super elastic properties\u0026sup1;⁰.\u003c/p\u003e \u003cp\u003eThe major metallic ions that leach out of the orthodontic appliances are Fe, Cr, and Ni. All the three elements potentially have adverse effects. But Ni and Cr with reported potential for producing allergic, toxic, carcinogenic effects have received the most attention⁹. Nickel has found to be carcinogenic in both in its free form as well as in complexes (chloride and sulphide).\u003c/p\u003e \u003cp\u003eNickel is said to have potential to induce oxidative stress through mechanisms such as induction of Cap43 (hypoxia-regulated gene), induction of HIF (Hypoxia Inducible Factors), elevation of lipid peroxidation, release of lactate dehydrogenase, increased acetaldehyde formation, histone hydrolysis and inhibition of histone H4 acetylation\u0026sup1;⁰.\u003c/p\u003e \u003cp\u003eIt is also hypothesized that nickel can cause potential DNA damage through the promotion of DNA strand scission (single strand breaks), induction of p53 and K-Ras alterations, inhibition of DNA repair enzymes, increase in DNA methylation, induction of silent gene expression by chromatin condensation, incorporation of critical genes into heterochromatin, and methylation of DNA resulting in silencing genetic activity necessary for the maintenance of normal cellular functions.\u0026sup1;⁰\u003c/p\u003e \u003cp\u003eBeing potent allergens or haptens, nickel ions can penetrate epithelial cells and produce various cytokines or chemokines that can result in activation of antigen presenting cells and T cells. Delayed hypersensitivity reaction after 48\u0026ndash;72 hours is seen following exposure.\u0026sup1;\u0026sup1;\u003c/p\u003e \u003cp\u003eA recent study done by Saghiri et al.\u0026sup1;\u0026sup2;, showed that in orthodontic patients with fixed appliances, cell phone radiation can influence the concentration of nickel in saliva in a time dependant manner. The increased presence of nickel ions was attributed to the increased flow of saliva due to radiation exposure from the cellular phones. With an increasing percentage of cell phone subscribers among the population and with regards adverse nature of the nickel ions, further research seems to be inevitable. Within this background, it could be implied that nickel ions leach into the oral cavity and may have potential implications for the patients undergoing orthodontic treatment. The present in vitro study investigated relationship between mobile phone radiation and the release of nickel ions among two groups of wires. The null hypothesis was that there would no difference in the nickel ions release with or without cellular radiation exposure.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cp\u003eEthical committee approval was obtained from the institutional ethical committee (IEC no.654/2015) before the commencement of the study. The study included four groups consisting of five pairs of 0.018 x 0.025 inch Orthodontic arch wires immersed in artificial saliva.\u003c/p\u003e \u003cp\u003eThey were divided into four groups (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Each group had five pairs of Orthodontic wires. The length of the arch wire\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e was determined with the help of an ideal typodont set, measured distally from the second molar tube of the right quadrant to the second molar tube on the left quadrant. The upper arch wire measured about 12.3 cm and the lower arch wire measured about 11.8 cm in length. The wires were employed in their \u0026ldquo;as received\u0026rdquo; condition after being cut to their specific lengths.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDescription of four study groups\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGroup I (Control Group)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.018 x 0.025 NiTi arch wires; not exposed to cellular radiation\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGroup II (Control Group)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.018x0.025 Stainless steel arch wires; not exposed to cellular radiation\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGroup III (Experimental Group)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.018x0.025 NiTi arch wires which were exposed to cellular radiation\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGroup IV (Experimental Group)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.018x0.025 Stainless Steel arch wires which were exposed to cellular radiation\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003ePreparation of artificial saliva was carried out which is specific in nature to study the corrosive nature of dental materials.\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e mention the ingredients used in preparation of artificial saliva.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComposition of Artificial Saliva\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIngredient\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eQuantity(mmol/l)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNa\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e15.33\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eK\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e5.37\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCa\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e5.40\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCl\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e23.02\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO\u003csub\u003e4\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e4.23\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUrea\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e16.65\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNa\u003csub\u003e2\u003c/sub\u003eS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e15.34\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eP\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e7\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe prepared artificial saliva (pH of 5.5\u0026ndash;6.0) was stored under refrigeration till the time of usage. Samples were housed in Glass petri dishes of dimensions 18x15 mm (Borosil, India) which facilitated the passage of radiation as well as which could hold the arch wires without inducing deformation.\u003c/p\u003e \u003cp\u003eBoth control and experimental group samples were immersed in 40 ml of artificial saliva and were stored at 37 degree Celsius. The petri dish was always covered with the help of a lid except during the time of radiation exposure to prevent evaporation of the immersion media (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe experimental groups were exposed to cellular radiation (900 Hertz) for a period of one hour everyday with help of a Gigahertz Transverse Electro Magnetic (GTEM) cell (Figs.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) which was fabricated based on the specifications given by Clemens\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e. It is an expanded transmission line which operates in the Transverse Electro Magnetic (TEM mode), with a characteristic impedance of 50Ω to avoid reflections.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIt is a pyramidal-shaped, tapered, dual-terminated section with its outer cell measuring about 220 cm (L) X 120 cm (B) X 80 cm (H), which provides a controllable and shielded environment for studying the effect of electromagnetic radiation in cellular and animal models. The EMF radiation source consists of a signal generator. It operates at a frequency range of 40MHz to 4.4GHz, a direction coupler and power meter (-30 to +\u0026thinsp;20dbm). The EMF chamber is equipped with RF absorbers. These further reduce the possibility of any reflections.\u003c/p\u003e \u003cp\u003eOn days 1, 7, 14, 21, and 28, the entire 40 ml of artificial saliva was agitated prior to removal. The samples were analysed within a period of half an hour with the help of atomic absorption spectrometry (AAS ICE 3300, Thermo Fisher Scientific, USA \u0026ndash; Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). It is an analytical technique that measures the concentrations of elements present in a solution. This technique works on the principle of specific wavelength absorption by an element. Replacement with a freshly prepared artificial saliva was carried out (on days 1,7,14, and 21) to avoid saturation of the ions in the medium as suggested by previous studies\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eAAS has the following three components: a light source, a sample cell to produce gaseous atoms, and a means to measure the specific light absorbed. There are several lamps present, which are held on a rotating turret specific to each element. With the help of a monochromator, a specific wavelength of light known as the spectral line is chosen, which is absorbed by the sample. A photomultiplier tube helps in producing an electrical signal that is proportional to the intensity of light absorbed.\u003c/p\u003e \u003cp\u003eThe sample, when atomised, is converted into ground state free atoms in the vapour state after which a beam of electromagnetic radiation is passed through the vaporised sample. The greater the number of atoms of a particular element, the greater the amount of radiation absorbed. The concentrations of the known samples are first tested, after which a calibration curve is constructed. The amount of standard absorbed is then used to calculate the concentration of the element in the unknown sample.\u003c/p\u003e \u003cp\u003eAtomisation of the study samples was carried out by means of aspiration of the solution onto the flame. This process converts the samples into their free atoms; irrespective of their initial state, the chemical form of the element is not of much significance. Working Standard solutions of nickel with a concentration of 1,3,5,7 mg/L were tested and calibrated prior to the testing of samples. Each study sample was aspirated and then tested thrice, after which the mean value was recorded. About 100 study samples in total were analysed in a period of one month.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eSTATISTICAL ANALYSIS\u003c/h2\u003e \u003cp\u003eAll the analysis was done using SPSS version 26. A p-value of \u0026lt;\u0026thinsp;0.05 was considered statistically significant. Normality of the data was assessed using Shapiro Wilks test. Comparison of mean values between the groups was done using Mann-Whitney U test.\u003c/p\u003e \u003c/div\u003e"},{"header":"RESULTS","content":"\u003cp\u003eThe NiTi Orthodontic wires exposed to cellular radiation showed significantly higher mean Nickel concentration on day 7th and 28th day (P\u0026thinsp;=\u0026thinsp;0.016 and 0.028) when compared to NiTi Orthodontic wires unexposed to cellular radiation. However, on day 21, NiTi Orthodontic wires unexposed to cellular radiation showed higher mean Nickel concentration than those exposed to cellular radiation (P\u0026thinsp;=\u0026thinsp;0.009). The SS Orthodontic wires unexposed to cellular radiation showed significantly higher mean Nickel concentration on day 14th and 21st day (P\u0026thinsp;=\u0026thinsp;0.028 and 0.028) when compared to SS Orthodontic wires exposed to cellular radiation (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMean and Standard deviation for the rates of Nickel release in mg/dl at days 1,7,14,21 and 28\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eControl\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eExperiment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMean\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSD\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMean\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSD\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNiTi Day 1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e.0280\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.0093\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.0401\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.0104\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.076\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNiTi Day 7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e.0116\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.0028\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.0186\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.0039\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.016\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNiTi Day 14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e.0154\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.0072\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.0187\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.0027\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.347\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNiTi Day 21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e.0290\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.0124\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.0030\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.0016\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.009\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNiTi Day 28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e.0064\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.0023\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.0241\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.0297\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.028\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSS Day 1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e.0411\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.0095\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.0525\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.0088\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.075\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSS Day 7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e.0166\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.0015\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.0211\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.0099\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.600\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSS Day 14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e.0136\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.0022\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.0064\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.0042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.028\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSS Day 21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e.0104\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.0080\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.0032\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.0012\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.028\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSS Day 28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e.0109\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.0031\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.0136\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.0012\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.117\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eOrthodontic treatment involves the usage of fixed appliances which consists of arch wires, bands, brackets and other auxiliaries that are fabricated with nickel containing alloys, which when placed in the oral cavity with a constantly reactive and changing environment can lead to corrosion of the metal components.\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003ePlacement of any material in the body creates an interface that is a site of many dynamic interactions between the body and the material or vice versa. The dynamics in these interactions will determine both the biological response to the material as well as the ability of the material to resist or survive corrosion in the body. Local and systematic effects produced by the material are modulated by substances that are released from it and the biological response to the same.\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eVarious in vitro and in vivo studies have investigated the release of metal ions such as nickel, chromium, iron, molybdenum from orthodontic appliances. Nickel is said to be a strong immunologic sensitizer, cytotoxic and also mutagenic in nature and hence has been a subject of concern to many researchers.\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eMany individuals worldwide are exposed to radiofrequency waves from cellular phones and other personal communication devices whose effect might be potentially detrimental to health.\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e During the period of usage, cellular phone lies near the head and the oral cavity. The presence of metallic components in the oral cavity of an orthodontic patient, compel the need to study the effect of cellular radiation on the same.\u003c/p\u003e \u003cp\u003eAn in vivo study carried out by Saghiri et al\u003csup\u003e12\u003c/sup\u003e showed that exposure to Radio Frequency Electro Magnetic Radiation emitted by mobile phones can result in time dependant increase in the nickel released from the fixed appliances. They attributed the increased nickel release to the greater flow rate of saliva and lower concentration of components in saliva which in turn resulted in more nickel released from fixed appliances into saliva.\u003c/p\u003e \u003cp\u003eAccording to the study, heat which is generated by the mobile phones can influence the properties, flow rate, pH, of saliva which can influence the corrosion rate of the orthodontic appliance. If there would be an increase in the flow rate of saliva due to cellular radiation, could a diluting effect on the concentration of corrosion products be anticipated rather than an increase of the same? Is there a possibility that the cellular radiation might have a direct effect on the increased rate of nickel release? Thus, this in vitro study was carried out to quantify nickel release from commonly used orthodontic wires exposed to cellular radiation.\u003c/p\u003e \u003cp\u003eThe findings of the present study indicate that cellular radiation can produce a statistical significant increase in the concentration of nickel ions. Higher mean concentration of nickel was attained on the 1st and on the 21st day in the NiTi control group and was about 0.028 mg/dl and 0.029 mg/dl respectively. The highest concentration of nickel in the NiTi experimental group was about 0.04 mg/dl attained on the 1st day.\u003c/p\u003e \u003cp\u003eThe highest concentration of nickel in the SS experimental group was about 0.050 mg/dl attained on the 1st day as compared to 0.041 in the SS control group.\u003c/p\u003e \u003cp\u003eIntergroup comparison between SS control (Group 2) and SS experimental (Group 4) shows a statistically significant increase in the concentration of nickel on days 14,21. The increase of nickel concentration was by about 53.3%,69% respectively in the experimental group.\u003c/p\u003e \u003cp\u003eFrom the above findings, one can note that exponential increase to nickel concentration resulted from exposure to radiation which was more evident in Group 3 than in Group 4 where the increase was observed only on days 14 and 21.\u003c/p\u003e \u003cp\u003eThe decrease in nickel release noted in the experimental groups at day 21 may be explained by the enhanced rate of corrosion in the early stages, leading to a depletion of nickel ions from the surface. This may have been followed by a temporary repassivation of the alloy surface. In contrast, a delay in corrosion was noted in the control groups, leading to a higher release of nickel ions at this time point. The increase noted in nickel release from day 28 may be attributed to a destabilization effect of the passive film because of prolonged irradiation which can be called as Non linear, time dependent corrosion phenomenon.\u003c/p\u003e \u003cp\u003eWe can categorize this dynamic process in to three phases \u0026ndash; early surface activation Day 1 to 7 (disruption of the passive oxide layer which releases the nickel into the saliva \u0026ndash; increase burst of nickel due to irradiation, surface depletion stage \u0026ndash; where surface nickel has leached out very less active nickel available which may result in the temporary reduction in the corrosion rate. Obviously in the controlled group there is delayed corrosion going on so at this point the control group shows more than the experimental group at Day 21. After this phase 3 \u0026ndash; Destabilization stage (secondary corrosion \u0026ndash; Day 28) continuous irradiation in the experimental group has caused destabilization of the repassivated layer has induced microstructural damage. This may be the reason we see spike in the Experimental group on day 28.\u003c/p\u003e \u003cp\u003eStatistically significant results were obtained in this in vitro study, which was not affected by the increased flow, diluting effect of the macromolecules present or due to an alteration of the pH of the saliva produced by the salivary gland after exposure to cellular radiation. Could the increase in the concentration of nickel be attributed to a direct effect of cellular radiation on the arch wire samples?\u003c/p\u003e \u003cp\u003eCellular radiation is nonionizing, electromagnetic in nature\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e. The resultant radiation can only result in excitation of the matter when it passes through. Could this excitation of atoms result in increase in the temperature of the matter resulting in increased corrosion of the same?\u003c/p\u003e \u003cp\u003eDielectric effect\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e of a material result when exposed to microwave and radiofrequency waves, in which heating occurs due to interaction of electric and magnetic fields with the material. Induced diploes can result which can lead to a rise in temperature. But the dielectric effect depends upon the dielectric properties of the material, material volume, and penetration depth of the waves used. Nickel nano fillers\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e have been used to increase the dielectric properties of composites in various engineering applications. Can the positive findings of the study be attributed to a possible dielectric effect?\u003c/p\u003e \u003cp\u003eAn increase in temperature affects the resistance to localized corrosion by reducing the ability of the material to repassivate\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e, thus contributing to increased nickel release in the arch wire samples exposed to radiation in this study\u003c/p\u003e \u003cp\u003eIn a study done by Barrett et al\u003csup\u003e13\u003c/sup\u003e, the overall release pattern of nickel was similar for both Nickel titanium and Stainless-steel appliances. A peak in nickel concentration was seen at day 7 followed by steady decline. Nickel release was greater in the stainless-steel appliances on day 14th (statistically significant).The average release of nickel during the four week period averaged 13.05 \u0026micro;g/day (single arch).\u003c/p\u003e \u003cp\u003eShearer and Park \u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e reported that the corrosion of orthodontic appliances reached plateau after a period of 6 days and did not increase after that. In this present study, the mean concentration of NiTi control (Group 1) and SS control (Group 2) peaked on the 1st day and declined after that except for day 21 in the NiTi Control (Group 1).Could the difference in the release kinetics be attributed to manufacturing process which could also play a role according to Eliades et al.\u003c/p\u003e \u003cp\u003eAnother interesting finding of this study is that average release during the period of one month were similar in all the four groups (0.017 mg/dl, 0.018 mg/dl, 0.016 mg/dl,0.019 mg/dl respectively). But there existed significant difference of the means during specific time intervals between the control and the experimental group. Could the exposure to cellular radiation cause an increased depletion of nickel ions from the surface of the arch wires during those time intervals?\u003c/p\u003e \u003cp\u003eThe dietary allowance of nickel is about 200\u0026ndash;300 \u0026micro;g per day\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e. Though the levels obtained during various in vitro investigations are lower than the above, the resultant might be sufficient to produce biological effects in the oral mucosa.\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eCellular radiation is said to be genotoxic, cyotoxic and co -carcionogenic in nature\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e. According to the results of this study, cellular radiation can cause increased release of nickel ions from orthodontic arch wires in a direct manner. Emphasis must be given to the findings of the study that cellular radiation can potentially present with a co - carcinogenic effect on the oral cavity in conjunction with increased release of nickel ions.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eThe effect of cellular radiation on Nickel release was evaluated in both Nickel Titanium and Stainless-steel arch wires. Mobile phone radiation can have a direct effect on the release of nickel ions from orthodontic arch wires. There seems to be an exponential increase in the concentration or the release of nickel to mobile phone radiation\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eFunding:\u003c/h2\u003e \u003cp\u003eNo funding was obtained for this study\u003c/p\u003e \u003cp\u003eAcknowledgements: None\u003c/p\u003e \u003cp\u003eData Availability: Included in the paper or Supplementary Information (for raw data, not summary data such as means and variances).\u003c/p\u003e \u003cp\u003eAll data supporting the findings of this study are available within the paper and its Supplementary Information.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eG S: Conceptualization, Data Curation, Formal Analysis, Methodology; ASU: Conceptualization, Project Administration;A V: Writing \u0026ndash; Review \u0026amp; Editing; KCP: Results ; KG: Supervision, Resources; ATP: Writing \u0026ndash; Review \u0026amp; Editing; S D: Original Draft Preparation, Writing \u0026ndash; Review \u0026amp; Editing.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eNone\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eIncluded in the paper or Supplementary Information (for raw data, not summary data such as means and variances).All data supporting the findings of this study are available within the paper and its Supplementary Information.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAoki, K. \u0026amp; Downes, E. J. An analysis of young people\u0026rsquo;s use of and attitudes toward cell phones. \u003cem\u003eTelematics Inform.\u003c/em\u003e \u003cb\u003e20\u003c/b\u003e (4), 349\u0026ndash;364 (2003).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHyland, G. J. Physics and biology of mobile telephony. \u003cem\u003eLancet\u003c/em\u003e \u003cb\u003e356\u003c/b\u003e (9244), 1833\u0026ndash;1836 (2000).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLai, H. \u0026amp; Singh, N. P. Acute low-intensity microwave exposure increases DNA single‐strand breaks in rat brain cells. \u003cem\u003eBioelectromagnetics\u003c/em\u003e \u003cb\u003e16\u003c/b\u003e (3), 207\u0026ndash;210 (1995).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLai, H. N. Single-and double-strand DNA breaks in rat brain cells after acute exposure to radiofrequency electromagnetic radiation. \u003cem\u003eInt. J. Radiat. Biol.\u003c/em\u003e \u003cb\u003e69\u003c/b\u003e (4), 513\u0026ndash;521 (1996).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLourencini da Silva, R., Albano, F., Lopes dos Santos, L. R., Tavares, A. D. Jr \u0026amp; Felzenszwalb, I. The effect of electromagnetic field exposure on the formation of DNA lesions. \u003cem\u003eRedox Rep.\u003c/em\u003e \u003cb\u003e5\u003c/b\u003e (5), 299\u0026ndash;301 (2000).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBhargava, S., Motwani, M. B. \u0026amp; Patni, V. M. Effect of handheld mobile phone use on parotid gland salivary flow rate and volume. Oral surgery, oral medicine, oral pathology and oral radiology. ;\u003cb\u003e114\u003c/b\u003e(2):200\u0026ndash;206. (2012).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDaroit, N. B., Visioli, F., Magnusson, A. S., Vieira, G. R. \u0026amp; Rados, P. V. Cell phone radiation effects on cytogenetic abnormalities of oral mucosal cells. \u003cem\u003eBrazilian oral Res.\u003c/em\u003e \u003cb\u003e29\u003c/b\u003e (1), 1\u0026ndash;8 (2015).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSouza, L. D., Cerqueira, E. D. \u0026amp; Meireles, J. R. Assessment of nuclear abnormalities in exfoliated cells from the oral epithelium of mobile phone users. \u003cem\u003eElectromagn. Biol. Med.\u003c/em\u003e \u003cb\u003e33\u003c/b\u003e (2), 98\u0026ndash;102 (2014).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEliades, T. \u0026amp; Athanasiou, A. E. In vivo aging of orthodontic alloys: implications for corrosion potential, nickel release, and biocompatibility. \u003cem\u003eAngle Orthod.\u003c/em\u003e \u003cb\u003e72\u003c/b\u003e (3), 222\u0026ndash;237 (2002).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEliades, T. \u0026amp; Bourauel, C. Intraoral aging of orthodontic materials: the picture we miss and its clinical relevance. \u003cem\u003eAm. J. Orthod. Dentofac. Orthop.\u003c/em\u003e \u003cb\u003e127\u003c/b\u003e (4), 403\u0026ndash;412 (2005).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSaito, M. et al. Molecular mechanisms of nickel allergy. \u003cem\u003eInt. J. Mol. Sci.\u003c/em\u003e \u003cb\u003e17\u003c/b\u003e (2), 202 (2016).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSaghiri, M. A., Orangi, J., Asatourian, A., Mehriar, P. \u0026amp; Sheibani, N. Effect of mobile phone use on metal ion release from fixed orthodontic appliances. \u003cem\u003eAm. J. Orthod. Dentofac. Orthop.\u003c/em\u003e \u003cb\u003e147\u003c/b\u003e (6), 719\u0026ndash;724 (2015).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBarrett, R. D., Bishara, S. E. \u0026amp; Quinn, J. K. Biodegradation of orthodontic appliances. Part I. Biodegradation of nickel and chromium in vitro. \u003cem\u003eAm. J. Orthod. Dentofac. Orthop.\u003c/em\u003e \u003cb\u003e103\u003c/b\u003e (1), 8\u0026ndash;14 (1993).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLeung, V. W. H. \u0026amp; Darvell, B. W. Artificial salivas for in vivo studies of dental materials. \u003cem\u003eJ. Dent.\u003c/em\u003e \u003cb\u003e25\u003c/b\u003e (6), 475\u0026ndash;484 (1997).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIcheln, C. The construction and application of a GTEM cell. \u003cem\u003eHUT Hmaburg\u003c/em\u003e Nov 1. (1995).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAnusavice, K. J. \u0026amp; Kenneth, J. \u003cem\u003ePhillips\u0026rsquo; science of dental materials\u003c/em\u003e (Mo: Saunders., 2003).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBehari, J. Biological responses of mobile phone frequency exposure. \u003cem\u003eIndian J. Exp. Biol.\u003c/em\u003e \u003cb\u003e48\u003c/b\u003e (10), 959\u0026ndash;981 (2010).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRoussy, G. \u0026amp; Pearce, J. A. Foundations and industrial applications of microwave and radio frequency fields: physical and chemical processes. (No Title). Jun 6. (1995).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJamal, E. M., Mohanan, P., Joy, P. A., Kurian, P. \u0026amp; Anantharaman, M. R. Effect of nickel nanofillers on the dielectric and magnetic properties of composites based on rubber in the X-band. \u003cem\u003eAppl. Phys. A\u003c/em\u003e. \u003cb\u003e97\u003c/b\u003e (1), 157\u0026ndash;165 (2009).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePark, H. Y. \u0026amp; Shearer, T. R. In vitro release of nickel and chromium from simulated orthodontic appliances. \u003cem\u003eAm. J. Orthod.\u003c/em\u003e \u003cb\u003e84\u003c/b\u003e (2), 156\u0026ndash;159 (1983).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNatarajan, M., Padmanabhan, S., Chitharanjan, A. \u0026amp; Narasimhan, M. Evaluation of the genotoxic effects of fixed appliances on oral mucosal cells and the relationship to nickel and chromium concentrations: an in-vivo study. \u003cem\u003eAm. J. Orthod. Dentofac. Orthop.\u003c/em\u003e \u003cb\u003e140\u003c/b\u003e (3), 383\u0026ndash;388 (2011).\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Arch wires, Cell Phones, Electromagnetic Radiation, Mass Spectrometry, Nickel Titanium, Stainless Steel","lastPublishedDoi":"10.21203/rs.3.rs-9343210/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9343210/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eAround 90 percent of the global population are constantly exposed to the electromagnetic radiation from handheld mobile phones. Due to the proximity of mobile phones to the oral cavity during the conversation period, the radiation emitted might influence the environment of the oral cavity. Few studies showed there was a time-dependent increase in nickel release among patients undergoing in orthodontic treatment who were exposed to cellular radiation. The increase in nickel was attributed to increased salivary flow due to mobile phone radiation. This in vitro study was carried out to analyse if nickel released is due to a direct effect of mobile radiation rather than due to increased flow of the saliva.\u003c/p\u003e \u003cp\u003eThis invitro study was planned with four groups containing five pairs of 18 x 25 Nickel titanium (NiTi) and Stainless steel (SS) orthodontic wires. These wires were immersed in 40 ml of artificial saliva. The experimental group (NiTi and SS) was exposed to cellular radiation (900 Hz) with help of an GTEM cell. The nickel release was assessed the 1st, 7th, 14th, 21st, and the 28th day using atomic mass Spectrometry.\u003c/p\u003e \u003cp\u003eThe NiTi Orthodontic wires exposed to cellular radiation showed significantly higher mean Nickel concentration on day 7th and 28th day (P\u0026thinsp;=\u0026thinsp;0.016 and 0.028) when compared to NiTi Orthodontic wires unexposed to cellular radiation. However, on day 21, NiTi Orthodontic wires unexposed to cellular radiation showed higher mean Nickel concentration than those exposed to cellular radiation (P\u0026thinsp;=\u0026thinsp;0.009). The SS Orthodontic wires unexposed to cellular radiation showed significantly higher mean Nickel concentration on day 14th and 21st day (P\u0026thinsp;=\u0026thinsp;0.028 and 0.028) when compared to SS Orthodontic wires exposed to cellular radiation. The findings of this study showed that increased Nickel concentrations in artificial saliva among NiTi orthodontic wires exposed to cellular radiation.\u003c/p\u003e","manuscriptTitle":"Effect of Cellular Radiation on Nickel Release from Fixed Orthodontic wires: An In Vitro Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-29 06:14:05","doi":"10.21203/rs.3.rs-9343210/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"1ce12503-5fa3-466d-a344-219da2061103","owner":[],"postedDate":"April 29th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Rejected","date":"2026-04-30T17:47:07+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-30T12:02:56+00:00","index":48,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":67054860,"name":"Health sciences/Health care"},{"id":67054861,"name":"Physical sciences/Materials science"},{"id":67054862,"name":"Health sciences/Medical research"}],"tags":[],"updatedAt":"2026-04-30T17:54:01+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-29 06:14:05","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9343210","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9343210","identity":"rs-9343210","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}