{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T10:06:50Z","timestamp":1789726010208,"version":"4.0.1"},"reference-count":24,"publisher":"MJS Publishing, Medical Journals Sweden AB","license":[{"start":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T00:00:00Z","timestamp":1789689600000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["BIiD"],"abstract":"<jats:p>Objective: This in vitro study aimed to evaluate the effect of Streptococcus mutans on the force alteration of nickel\u2013titanium (NiTi) open-coil springs under constant compression.\nMaterials and methods: Sixty NiTi open-coil springs from three commercial brands (3M, Ormco, and American Orthodontics [AO]) were standardized to a resting length of 15 mm and compressed with a 240-g load using an Instron\u00ae universal testing machine. Each brand was divided into control (immersed in artificial saliva) and experimental (exposed to S. mutans in Brain Heart Infusion medium) conditions. Samples were incubated at 37\u00b0C for 30 days, after which force levels at 0.5, 3.25, and 6.5 mm displacements were remeasured. Data were analyzed with paired t-tests, one-way analysis of variance, and Tukey\u2019s post hoc tests (p &lt; 0.05).Results: All brands exhibited force increases after 30 days, though with heterogeneous patterns. 3M springs maintained relatively stable behavior, with consistent force increments across all displacements in both conditions. AO springs showed irregular responses, with losses at some displacements and substantial gains at others, especially under bacterial exposure. Ormco springs displayed the highest variability and most pronounced increases, with force gains exceeding 80 gf, suggesting possible microstructural modifications.Conclusions: Force stability in NiTi open-coil springs is brand-dependent and influenced by bacterial exposure. While 3M springs demonstrated predictable performance, AO and Ormco exhibited less consistent behavior, which may risk excessive force application during clinical use. These findings highlight the importance of considering biological and environmental factors in the selection and monitoring of NiTi coil springs.<\/jats:p>","DOI":"10.2340\/biid.v13.46766","type":"journal-article","created":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T09:36:50Z","timestamp":1789724210000},"page":"729-734","source":"Crossref","is-referenced-by-count":0,"title":["Impact of bacterial exposure on the mechanical behavior of nickel\u2013titanium open-coil springs"],"prefix":"10.2340","volume":"13","author":[{"given":"Diego Paul","family":"Hidalgo Mu\u00f1\u00f3z","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mauricio","family":"Aguirre Balseca","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marjory Elizabeth","family":"Vaca Zapata","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karina Maria Salvatore","family":"Freitas","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stalin Wladimir","family":"Tamami Tualombo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1183","published-online":{"date-parts":[[2026,9,18]]},"reference":[{"key":"168726","doi-asserted-by":"crossref","unstructured":"Alcaraz I, Moyano J, P\u00e0mies A, Ruiz G, Art\u00e9s M, Gil J, et al. 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Semin Orthod. 2017;23:382\u20139.","DOI":"10.1053\/j.sodo.2017.07.008"},{"key":"168730","doi-asserted-by":"crossref","unstructured":"Santos AC, Tortamano A, Naccarato SR, Dominguez-Rodriguez GC, Vigorito JW. An in vitro comparison of the force decay generated by different commercially available elastomeric chains and NiTi closed coil springs. Braz Oral Res. 2007;21:51\u20137.","DOI":"10.1590\/S1806-83242007000100009"},{"key":"168731","doi-asserted-by":"crossref","unstructured":"Vieira CIV, Reis J, Vaz LG, Martins LP, Martins RP. Deformation of nickel-titanium closed coil springs: an in vitro study. Dental Press J Orthod. 2017;22:38\u201346.","DOI":"10.1590\/2177-6709.22.1.038-046.oar"},{"key":"168732","doi-asserted-by":"crossref","unstructured":"Angolkar PV, Arnold JV, Nanda RS, Duncanson MG, Jr. Force degradation of closed coil springs: an in vitro evaluation. Am J Orthod Dentofacial Orthop. 1992;102:127\u201333.","DOI":"10.1016\/0889-5406(92)70024-5"},{"key":"168733","doi-asserted-by":"crossref","unstructured":"Ohara AT. Clinical importance of austenitic final point in the selection of nickel-titanium alloys for application in orthodontic-use arches. Rev Odontol Mex. 2016;20:e162\u20139.","DOI":"10.1016\/j.rodmex.2016.08.012"},{"key":"168734","doi-asserted-by":"crossref","unstructured":"Bahije L, Benyahia H, El Hamzaoui S, Ebn Touhami M, Bengueddour R, Rerhrhaye W, et al. Behavior of NiTi in the presence of oral bacteria: corrosion by Streptococcus mutans. Int Orthod. 2011;9:110\u201319.","DOI":"10.1016\/j.ortho.2010.12.001"},{"key":"168735","doi-asserted-by":"crossref","unstructured":"Abraham KS, Jagdish N, Kailasam V, Padmanabhan S. Streptococcus mutans adhesion on nickel titanium (NiTi) and copper-NiTi archwires: a comparative prospective clinical study. Angle Orthod. 2017;87:448\u201354.","DOI":"10.2319\/040516-270.1"},{"key":"168736","doi-asserted-by":"crossref","unstructured":"Banas JA, Drake DR. Are the mutans streptococci still considered relevant to understanding the microbial etiology of dental caries? BMC Oral Health. 2018;18:129.","DOI":"10.1186\/s12903-018-0595-2"},{"key":"168737","doi-asserted-by":"crossref","unstructured":"Titiz S, Keskin Erdo\u011fan Z, Hames Tuna EE, Aras A. Nickel release and the viability of Streptococcus mutans corresponding to low risk of dental caries in artificial saliva containing orthodontic appliances: in vitro study. Turk J Orthod. 2022;35:157\u201365.","DOI":"10.5152\/TurkJOrthod.2022.21142"},{"key":"168738","doi-asserted-by":"crossref","unstructured":"Oliveira DC, Thomson JJ, Alhabeil JA, Toma JM, Plecha SC, Pacheco RR, et al. In vitro Streptococcus mutans adhesion and biofilm formation on different esthetic orthodontic archwires. Angle Orthod. 2021;91:786\u201393.","DOI":"10.2319\/121220-998.1"},{"key":"168739","doi-asserted-by":"crossref","unstructured":"Yang L, Lv C, Li X, Feng J. Force degradation of two orthodontic accessories analyzed in vivo and in vitro. BMC Oral Health. 2023;23(1):1001.","DOI":"10.1186\/s12903-023-03737-x"},{"key":"168740","doi-asserted-by":"crossref","unstructured":"Duerig T. The metallurgy of nitinol as it pertains to medical devices. In: Froes FH, Qian M, editors. Titanium in medical and dental applications. Duxford: Woodhead Publishing; 2018. p. 555\u201370.","DOI":"10.1016\/B978-0-12-812456-7.00025-1"},{"key":"168741","doi-asserted-by":"crossref","unstructured":"Prado T, Guilherme Neves J, Correr-Sobrinho L, Carmo Menezes C, Cherubini Venezian G, Bortolazzo Correr A, et al. Evaluation of the force degradation and deformation of the open-closed and open springs of NiTi: an in vitro study. 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Comprehensive evaluation of the antibacterial and antibiofilm activities of NiTi orthodontic wires coated with silver nanoparticles and nanocomposites: an in vitro study. BMC Oral Health. 2024;24:1345.","DOI":"10.1186\/s12903-024-05104-w"},{"key":"168749","doi-asserted-by":"crossref","unstructured":"Nafarrate-Valdez RA, Martinez-Martinez RE, Zaragoza-Contreras EA, Ayala-Herrera JL, Dominguez-Perez RA, Reyes-Lopez SY, et al. Anti-adherence and antimicrobial activities of silver nanoparticles against serotypes C and K of Streptococcus mutans on orthodontic appliances. Medicina (Kaunas). 2022;58:877.","DOI":"10.3390\/medicina58070877"}],"container-title":["Biomaterial Investigations in Dentistry"],"original-title":[],"link":[{"URL":"https:\/\/medicaljournalssweden.se\/biid\/article\/download\/46766\/55532","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/medicaljournalssweden.se\/biid\/article\/download\/46766\/55532","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T09:37:03Z","timestamp":1789724223000},"score":1,"resource":{"primary":{"URL":"https:\/\/medicaljournalssweden.se\/biid\/article\/view\/46766"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,18]]},"references-count":24,"URL":"https:\/\/doi.org\/10.2340\/biid.v13.46766","relation":{},"ISSN":["2641-5275"],"issn-type":[{"value":"2641-5275","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,18]]}}}