Comparison of Preformed Orthodontic Archwires with Modified Dental Arch Forms: A Cross-Sectional Study

Comparison of Preformed Orthodontic Archwires with Modified Dental Arch Forms: A Cross-Sectional 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 Research Article Comparison of Preformed Orthodontic Archwires with Modified Dental Arch Forms: A Cross-Sectional Study Faris Al-Jobur, Ramy Ishaq, Mohammed Al‑Labani, Khalid Al‑Dhorae, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8309904/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 11 You are reading this latest preprint version Abstract Background Selecting an archwire that respects a patient’s native arch form is central to stability and periodontal safety. Evidence from the last five years shows substantial heterogeneity in arch dimensions across populations, with contemporary preformed nickel–titanium (NiTi) archwires often wider than natural arches at the canine level. [ 1 – 6 ] This study quantified Yemeni adult arch dimensions and predominant arch forms and compared them with commonly used preformed NiTi archwires using a bracket‑point–based reference graph. Methods In this cross‑sectional analysis, pretreatment casts from 222 subjects (Class I and II; 16–28 years) were digitized. Clinical bracket points defined transverse widths (intercanine, Wc; intermolar, Wm) and depths (Dc, Dm). Arch form was categorized as tapered, ovoid, or square. Twenty‑seven rectangular 0.019×0.025‑inch NiTi archwires from 11 manufacturers were traced on a CBP reference grid that incorporated bracket‑base offsets. Archwire widths at the canine (L3) and first‑molar (L6) levels were compared with sample means. Repeatability was assessed on a subsample. [ 7 – 13 ] Results Ovoid was the predominant arch form followed by tapered and square. Males exhibited larger transverse dimensions than females. Across brands, most preformed NiTi archwires were wider than natural arches at the canine level. Mean (archwire – arch) differences were approximately + 3.4 mm at maxillary canines and + 1.9 mm at maxillary first molars; in the mandible, + 4.1 mm at canines and + 1.5 mm at first molars. Closest overall matches were 3M Ortho Form I (tapered), Dentaurum Arch Form I (tapered), and Ormco Ortho Small. [ 3 , 5 , 6 , 14 – 18 ] Conclusions No single preformed archwire matched the Yemeni adult sample across arches and landmarks. Clinical selection should bias toward archwires ≈ 3–4 mm narrower at canines and ≈ 2 mm narrower at first molars to preserve patient‑specific arch forms, with individualized adjustments where needed. Reporting followed STROBE. [ 19 , 20 ] arch form preformed archwires nickel–titanium intercanine width intermolar width Yemeni population bracket points Figures Figure 1 Figure 2 Background Preservation of a patient’s original arch form is a cornerstone of orthodontic stability and periodontal safety. Recent evidence emphasizes that arch dimensions and shapes vary by sex and ancestry and are influenced by genetic and environmental factors. [ 1 , 2 , 21 – 23 ] Preformed NiTi archwires—engineered for favorable load‑deflection properties—are widely employed during alignment and leveling, yet their standardized shapes do not necessarily reflect the diversity of natural arches. [ 3 – 6 , 24 ] Multiple studies since 2020 have shown inconsistency between commercial archwire forms and clinical arch forms at key landmarks, especially at the canine level where standardized wires are commonly wider. [ 3 , 5 , 6 , 14 , 18 ] Moreover, the increasing adoption of digital workflows has improved the precision of arch form measurement and setup through three‑dimensional dental models. [ 8 – 11 , 25 – 27 ] NiTi metallurgy has continued to evolve, including heat‑activated and copper‑NiTi variants; nevertheless, randomized trials demonstrate similar early alignment efficiency across many NiTi types, shifting clinical emphasis toward wire form rather than solely alloy subtype. [ 4 , 28 – 31 ] Customized CAD/CAM appliances and robotic wire bending provide promising avenues for individualized archwire design, but preformed labial archwires remain dominant in daily practice. [ 12 , 32 – 36 ] For clinicians operating in under‑represented populations, such as Yemeni adults, local normative data remain essential to reduce unnecessary transverse expansion, minimize periodontal risk, and support long‑term stability. [ 21 , 22 ] This study reports population‑specific arch dimensions and predominant arch forms and benchmarks the fit of commonly used preformed NiTi archwires against a bracket‑point–based reference graph. Methods Study design and setting Design: Cross‑sectional study using pretreatment casts from university clinics and private practices in Sana’a, Yemen, following STROBE. [ 19 , 20 ] Participants: 222 subjects aged 16–28 years with permanent dentitions (excluding third molars), Angle Class I or II, no prior orthodontic treatment. Measurements: Clinical bracket points (CBPs) were used to compute Wc, Wm, Dc, Dm and proportional indices; arch forms were categorized (tapered, ovoid, square). Archwire benchmarking: Twenty‑seven 0.019×0.025‑inch NiTi preformed archwires (11 manufacturers) were traced on a CBP reference grid with bracket‑base offsets; widths at L3 and L6 were compared to sample means. Statistics: Group comparisons by t‑tests/ANOVA; repeatability assessed by ICC, consistent with contemporary guidance. [ 13 ] Sampling frame and sample size Sampling frame and size: Records from two university clinics and three private orthodontic practices were screened. A priori, we targeted ≥ 200 subjects to estimate mean transverse widths within ± 0.5 mm at 95% confidence, assuming SD ≈ 3 mm based on pilot data and contemporary literature. This also provided ≥ 80% power to detect sex‑related differences ≥ 1.5 mm in Wc and Wm using two‑sided α = 0.05. Eligibility criteria mirrored everyday case mix to enhance external validity while excluding conditions that distort landmarks (e.g., large restorations encroaching on CBPs). Participants and eligibility Design: Cross‑sectional study using pretreatment casts from university clinics and private practices in Sana’a, Yemen, following STROBE. [ 19 , 20 ] Participants: 222 subjects aged 16–28 years with permanent dentitions (excluding third molars), Angle Class I or II, no prior orthodontic treatment. Measurements: Clinical bracket points (CBPs) were used to compute Wc, Wm, Dc, Dm and proportional indices; arch forms were categorized (tapered, ovoid, square). Archwire benchmarking: Twenty‑seven 0.019×0.025‑inch NiTi preformed archwires (11 manufacturers) were traced on a CBP reference grid with bracket‑base offsets; widths at L3 and L6 were compared to sample means. Statistics: Group comparisons by t‑tests/ANOVA; repeatability assessed by ICC, consistent with contemporary guidance. [ 13 ] Model digitization and quality control Model digitization and quality control: Alginate impressions were poured within 30 minutes using vacuum‑mixed ISO Type 3 dental stone. Casts were scanned on a laboratory scanner with manufacturer‑specified trueness ≤ 20 µm; STL files were inspected for holes and artifacts. The occlusal plane was standardized by three‑point orientation (incisal midpoint and mesiobuccal cusp tips of first molars) to minimize projection bias. Landmarks were placed on CBPs identified as the midpoint of the bracket footprint per crown, consistent with current digital measurement guidance. [ 8 – 11 , 25 ] Landmarks and measurements Design: Cross‑sectional study using pretreatment casts from university clinics and private practices in Sana’a, Yemen, following STROBE. [ 19 , 20 ] Participants: 222 subjects aged 16–28 years with permanent dentitions (excluding third molars), Angle Class I or II, no prior orthodontic treatment. Measurements: Clinical bracket points (CBPs) were used to compute Wc, Wm, Dc, Dm and proportional indices; arch forms were categorized (tapered, ovoid, square). Archwire benchmarking: Twenty‑seven 0.019×0.025‑inch NiTi preformed archwires (11 manufacturers) were traced on a CBP reference grid with bracket‑base offsets; widths at L3 and L6 were compared to sample means. Statistics: Group comparisons by t‑tests/ANOVA; repeatability assessed by ICC, consistent with contemporary guidance. [ 13 ] Reference grid construction: The CBP reference grid comprised a sixth‑order polynomial representation of the clinical archwire path with superimposed bracket‑base thickness offsets (0.4–0.6 mm anterior, 0.6–0.8 mm posterior) to better emulate the wire trajectory rather than the enamel surface. Widths at L3 and L6 were computed as chord lengths between left/right CBPs; depths were orthogonal distances from the midline to the chord lines. Proportional indices (WDc, WDm) were recorded to capture anterior vs posterior fullness independent of absolute size. Reference grid and archwire evaluation Design: Cross‑sectional study using pretreatment casts from university clinics and private practices in Sana’a, Yemen, following STROBE. [ 19 , 20 ] Participants: 222 subjects aged 16–28 years with permanent dentitions (excluding third molars), Angle Class I or II, no prior orthodontic treatment. Measurements: Clinical bracket points (CBPs) were used to compute Wc, Wm, Dc, Dm and proportional indices; arch forms were categorized (tapered, ovoid, square). Archwire benchmarking: Twenty‑seven 0.019×0.025‑inch NiTi preformed archwires (11 manufacturers) were traced on a CBP reference grid with bracket‑base offsets; widths at L3 and L6 were compared to sample means. Statistics: Group comparisons by t‑tests/ANOVA; repeatability assessed by ICC, consistent with contemporary guidance. [ 13 ] Reference grid construction: The CBP reference grid comprised a sixth‑order polynomial representation of the clinical archwire path with superimposed bracket‑base thickness offsets (0.4–0.6 mm anterior, 0.6–0.8 mm posterior) to better emulate the wire trajectory rather than the enamel surface. Widths at L3 and L6 were computed as chord lengths between left/right CBPs; depths were orthogonal distances from the midline to the chord lines. Proportional indices (WDc, WDm) were recorded to capture anterior vs posterior fullness independent of absolute size. Archwire inventory: Eleven manufacturers were represented (e.g., 3M, Dentaurum, Ormco, American Orthodontics, Rocky Mountain Orthodontics, G&H, etc.). All wires were rectangular 0.019×0.025‑inch NiTi intended for finishing/working arch stages to ensure cross‑brand comparability; when a line offered multiple shapes, the most clinically used tapered/ovoid forms were prioritized. Width measurements were performed at bracket‑position coordinates derived from average tooth dimensions to reflect clinically engaged segments. [ 3 , 10 , 15 ] Arch form categorization Arch form categorization: Following contemporary practice, arches were categorized into tapered, ovoid, or square based on an automated best‑fit to canonical templates using root‑mean‑square (RMS) error minimization, then visually verified by two calibrated examiners. Disagreements were resolved by consensus; Cohen’s κ was computed for interrater agreement on form categories. Outcomes Primary outcomes were archwire–arch width differences at L3 and L6 for maxillary and mandibular arches; secondary outcomes included arch‑form distribution and sex differences in transverse dimensions. Statistical analysis Statistical plan: Normality was assessed by Shapiro–Wilk and homoscedasticity by Levene tests. Sex comparisons used independent‑samples t‑tests or Mann–Whitney U as indicated; arch form distribution by sex used χ² tests. For wire‑to‑arch comparisons, we summarized mean differences and their 95% CIs at L3 and L6 for each archwire model; one‑sample tests evaluated whether the mean difference deviated from 0 mm. Equivalence analyses used two one‑sided tests (TOST) with prespecified equivalence margins of ± 1.0 mm at L3 and ± 1.5 mm at L6, aligned with clinically acceptable bounds informed by contemporary orthodontic guidance. [ 4 , 13 ] Multiplicity was addressed by Benjamini–Hochberg FDR control (q = 0.10) given the benchmarking nature of the analysis. Reliability and repeatability Repeatability and reliability: Ten percent of casts were re‑landmarked and re‑measured after a two‑week washout period by the same examiner and by an independent examiner. We report ICC(2,1) for absolute agreement with 95% CIs for Wc, Wm, Dc, and Dm; Bland–Altman plots confirmed absence of systematic bias. [ 13 ] Category agreement for arch form used quadratic‑weighted κ and percent agreement; pre‑specified thresholds for acceptable reliability were ICC ≥ 0.90 and κ ≥ 0.80. Sensitivity analyses Sensitivity analyses: (1) Restriction to Class I subjects; (2) Stratification by sex; (3) Substitution of enamel‑based landmarks (FA points) for CBPs to evaluate robustness of width estimates. Results were directionally stable across sensitivity analyses (details available on request). Ethics Institutional approval and consent were obtained; full details are provided in Declarations. Results Ovoid arch form predominated. Males showed larger transverse dimensions. Mean benchmarks: Maxilla Wc 35.92 mm, Wm 54.54 mm; Mandible Wc 28.37 mm, Wm 48.85 mm. Most preformed NiTi archwires exceeded natural canine widths; mean archwire–arch differences were + 3.38 mm (maxillary L3), + 1.94 mm (maxillary L6), + 4.05 mm (mandibular L3), + 1.53 mm (mandibular L6). Best matches overall: 3M Ortho Form I (tapered), Dentaurum Arch Form I (tapered), Ormco Ortho Small. Discussion Findings align with recent literature reporting mismatch between commercial archwire geometries and clinical arch forms, notably at the canine level. [ 3 , 5 , 6 , 14 , 16 – 18 ] Given comparable alignment efficiency among NiTi subtypes, clinicians should prioritize wire form to preserve native arches, supplementing with individualized bends as needed. [ 4 , 28 – 31 ] Digital measurement reliability is high, and customized appliances can realize target forms accurately, though posterior overcorrection may be necessary. [ 7 – 12 , 25 – 27 ] For expansion therapies, predictability diminishes posteriorly and skeletal gains are unlikely; maintaining pretreatment intercanine width supports stability. [ 37 – 41 ] Strengths include sample size and CBP‑based 3D measurements; limitations include regional product availability and reliance on mean fits. Comparison with contemporary literature Our findings echo contemporary bench and clinical evidence. Force‑mapping studies demonstrate that wire geometry materially influences force vectors along the arch; narrower anterior segments reduce proclination forces at L3 while broader posterior segments can increase expansion moments at L6. [ 10 , 14 , 18 ] Recent AJODO work measuring preformed wire dimensions at bracket positions confirms nontrivial inter‑brand variation and highlights that nominally similar ‘tapered’ designs can diverge by several millimeters at key landmarks. [ 3 , 15 ] Systematic reviews on expansion with aligners and fixed appliances converge on higher predictability in premolar regions with diminishing returns posteriorly, aligning with our recommendation to avoid broad default forms without corroborating skeletal support. [ 1 , 37 , 38 ] Furthermore, long‑term studies associate excessive increases in intermolar width with greater relapse risk, whereas conservative maintenance of intercanine width tends to enhance anterior stability. [ 39 – 41 ] Compared with studies from East Asian and European cohorts, the Yemeni sample displayed similar qualitative distribution of arch forms (ovoid predominance) but smaller absolute intercanine widths, particularly in the mandible. This suggests that wire catalogs configured around North American/European averages may require additional narrow, tapered options for Middle Eastern populations to minimize unintended expansion. Population context and external validity The Yemeni adult cohort reflects a typical university/private‑practice case mix in an urban setting. While our results may generalize to neighboring populations with shared ancestry and environmental exposures, clinicians should consider local anthropometric data wherever possible. Genetic‑environmental interactions in arch development are increasingly recognized; heritability estimates for arch dimensions are moderate, but habits, diet consistency, and respiratory patterns also contribute. [ 2 , 21 , 22 ] Thus, the present normative values should be viewed as guidance to inform individualized selection rather than prescriptive targets. Practical workflow checklist for wire selection 1) Acquire calibrated digital models and standardize orientation; verify trueness and fill holes. [ 8 – 11 , 25 ] 2) Measure Wc/Wm and Dc/Dm at CBPs; categorize arch form against canonical templates (tapered, ovoid, square) and record sex and Angle class. 3) Screen manufacturer catalogs for the narrowest viable anterior dimension matching the patient’s Wc within ± 1–2 mm; prefer tapered forms when category is ambiguous. [ 3 , 5 , 6 , 15 ] 4) Evaluate posterior fit at L6; deviations up to ~ 2 mm may be acceptable in healthy periodontium but reassess in thin buccal bone phenotypes. [ 36 ] 5) If canine mismatch exceeds ~ 3–4 mm, add compensatory constriction bends or select a narrower archwire model; confirm incisor inclination targets to avoid iatrogenic proclination. 6) Reassess fit at finishing; introduce minor individualized bends rather than switching to broad forms that could undermine anterior stability. 7) Document measurements and rationale to support reproducibility and outcome auditing. Data robustness and quality assurance We adopted multiple safeguards to ensure data quality: laboratory scanning with high trueness, landmarking protocols aligned with digital reliability guidance, blinded repeat measurements, and pre‑registered equivalence bounds to discourage post‑hoc thresholding. Despite these safeguards, residual sources of imprecision include scanner stitching near interproximal contacts, CBP estimation on abraded enamel, and variations in bracket‑base thickness between products. However, the magnitude of observed wire‑arch mismatches (≈ 3–4 mm at L3) substantially exceeds plausible measurement error, strengthening the clinical signal. Clinical implications Archwire selection should begin with an assessment of the patient’s baseline arch form and transverse dimensions on calibrated digital models. If a preformed wire exceeds native Wc by > 3 mm, clinicians should consider a narrower tapered option or introduce compensatory constriction bends anteriorly to avoid proclination and periodontal strain. Posteriorly, deviations ≤ 2 mm at L6 are less likely to induce undesirable expansion, but caution is advised in reduced buccal bone thickness scenarios, where CBCT studies highlight potential dehiscence risk with broad forms. [ 36 ] In aligner therapy or hybrid protocols, recent systematic reviews indicate expansion predictability decreases posteriorly and skeletal effects are minimal; therefore, broad targets must be tempered by biological constraints. [ 37 , 38 ] For finishing phases using rectangular NiTi, minor customized bends can fine‑tune intercanine relationships while keeping overall wire geometry close to the patient’s pretreatment form. In practices with access to CAD/CAM or robotic wire‑bending, customized geometries can be derived directly from CBPs and verified with force‑mapping to ensure biologically sound loading. [ 7 , 10 , 12 , 32 – 35 ] Limitations and future research The benchmarking approach used mean arch values, which may obscure subject‑level mismatches; future work should conduct case‑matched wire fitting and prospectively evaluate periodontal and stability outcomes. Bracket prescription and wire slot size can alter the effective archwire path; although bracket‑base offsets were modeled, true in‑vivo trajectories may vary with adhesive thickness and torque play. The archwire portfolio reflects commonly available products in the study region; inclusion of additional global products could refine generalizability. Finally, while CBCT evidence suggests caution with buccal expansion in thin biotypes, direct imaging was beyond scope here. Randomized clinical trials that compare preformed vs customized archwire geometry with hard/soft tissue endpoints would be informative. Concluding clinical recommendations In daily practice, selecting a preformed archwire that respects native transverse dimensions is both feasible and impactful. For adult Yemeni patients similar to those studied here, we advise: (a) begin with a tapered archwire whose anterior width is within ~ 1–2 mm of the patient’s measured Wc; (b) avoid broad, square forms unless dentoalveolar expansion is specifically indicated and biologically supported; (c) verify posterior fit at L6 and limit default expansion to ≤ 2 mm in the absence of skeletal support; (d) leverage finishing bends to individualize rather than swapping to substantially broader stock forms; and (e) document measurements, chosen wire geometry, and rationale. These simple steps, grounded in 2020–2025 evidence and enabled by accessible digital tools, can help reduce iatrogenic proclination, preserve periodontal health, and support durable, esthetic outcomes. Finally, beyond the specific product matches identified herein, the overarching message is conceptual: preformed archwires should be treated as templates to be critically appraised against each patient’s anatomy rather than default trajectories. As digital orthodontics matures, routine integration of standardized CBP‑based measurements, transparent reliability reporting, and explicit equivalence margins in comparative evaluations will foster higher quality evidence and more consistent care. We encourage researchers to publish open measurement datasets and wire geometries to accelerate cumulative progress and enable independent replication. Conclusions Preformed NiTi archwires frequently over‑expand canine widths in Yemeni adults. Selecting narrower preformed forms at L3 and slightly narrower at L6 can better preserve individual arch forms. No single product matched all metrics; individualized adjustments remain necessary. Declarations Ethics approval and consent to participate: Approved by the University of Science and Technology Medical Ethical Committee (Sana’a, Yemen); written informed consent was obtained from all participants. Approval reference number: (EAC/UST172). Availability of data and materials: De‑identified data, archwire measurements, and analysis scripts are available from the corresponding author on reasonable request. Consent for publication: Not applicable (no identifiable individual data are included). Competing interests: None declared. Funding: None. Authors’ contributions: Conceptualization FJ; RI; methodology, FJ; ML; RI; software, FJ and RI; formal analysis, SH and FJ; investigation, SH; and KD; data curation, SA; and RI; writing original draft preparation SH and RI; writing, review and editing SH and KD; supervision RI and ML; funding acquisition, SH; administration: SH. All authors have read and agreed to the published version of the manuscript. Tables 1–4 are provided as a separate DOCX and CSV files to match BMC submission preferences. References Ma J, et al. Clinical outcomes of Invisalign therapy in arch expansion: a systematic review. BMC Oral Health. 2023;23:302. https://doi.org/10.1186/s12903-023-03302-6 . Giri J, et al. Heritability of dental arches and occlusal characteristics: a systematic review and meta–analysis. Eur J Orthod. 2023;45(6):854–67. https://doi.org/10.1093/ejo/cjad061 . Shigenobu Y, et al. The dimensions of preformed nickel–titanium archwires measured at bracket positions. 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Records: collection and management guidelines for digital models. 2022. https://bos.org.uk/professionals-members/advice-sheets-and-guidelines/ Tables Table 1 to 4 are available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files Table1.csv Table2.csv Table3.csv Table4.csv Tables.docx STROBEChecklist.docx Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 27 Jan, 2026 Reviews received at journal 12 Jan, 2026 Reviews received at journal 12 Jan, 2026 Reviewers agreed at journal 09 Jan, 2026 Reviewers agreed at journal 05 Jan, 2026 Reviewers agreed at journal 02 Jan, 2026 Reviewers invited by journal 31 Dec, 2025 Editor invited by journal 10 Dec, 2025 Editor assigned by journal 08 Dec, 2025 Submission checks completed at journal 08 Dec, 2025 First submitted to journal 08 Dec, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8309904","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":559360570,"identity":"e89eb563-6ed1-45fe-8d3f-5d642d5dc442","order_by":0,"name":"Faris Al-Jobur","email":"","orcid":"","institution":"University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Faris","middleName":"","lastName":"Al-Jobur","suffix":""},{"id":559360571,"identity":"278cfbb6-dcc6-4bb2-add1-e29940c0ca25","order_by":1,"name":"Ramy Ishaq","email":"","orcid":"","institution":"Sana'a University","correspondingAuthor":false,"prefix":"","firstName":"Ramy","middleName":"","lastName":"Ishaq","suffix":""},{"id":559360572,"identity":"b564f735-11f6-4ebd-8d68-235ea0168b8f","order_by":2,"name":"Mohammed Al‑Labani","email":"","orcid":"","institution":"University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Mohammed","middleName":"","lastName":"Al‑Labani","suffix":""},{"id":559360573,"identity":"aff07cd9-be7c-49ef-92ee-4eafe0024fce","order_by":3,"name":"Khalid Al‑Dhorae","email":"","orcid":"","institution":"Ibn Al-Nafis for Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Khalid","middleName":"","lastName":"Al‑Dhorae","suffix":""},{"id":559360574,"identity":"bcfe9480-59e6-4ef3-ac42-8c378630df1a","order_by":4,"name":"Salah M. Bin Hafedh","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABAElEQVRIie3RMWrDMBSA4Sc8eHnQjioadAWFgqC0JVexMWRyaKfWo4LBXZRkzUm81kHQKQcwqENNIVOHQBfTZqhCuto4W6H6Qdo+pCcB+Hx/skAFABWECiTshhFyJFiBJKuTSYBDAH9azz7v4ZVjmJfvN18lB5pU0GZlJxGbOGcr2I40vjxeThd2pOgkInpjuwnEiiEY8kxTyabaRuM6FQEpuglfNvm3I2PNPyS7cgTo3a6XQB0Xh1NiTVEyaA8khV4i6qa4RmESjZOHi7lys+BWrPtm4cvEWMzMrQ5NSdu95RAmzVub9Vzs9xGOkcJt55H7puHt3To7Bfh8Pt9/6AeyMljrg5+bbAAAAABJRU5ErkJggg==","orcid":"","institution":"Sana'a University","correspondingAuthor":true,"prefix":"","firstName":"Salah","middleName":"M. 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13:55:05","extension":"html","order_by":17,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":101584,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-8309904/v1/523e14513610fbc75d6838c8.html"},{"id":99238130,"identity":"77baf677-1f76-4e88-941f-bf1ae5f13abd","added_by":"auto","created_at":"2025-12-30 13:55:07","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":88947,"visible":true,"origin":"","legend":"\u003cp\u003eMeasurement landmarks and definitions at L3 (canine) and L6 (first‑molar) levels; Wc/Wm = transverse widths (horizontal chords), Dc/Dm = depths (vertical).\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-8309904/v1/0a9b81bad0921e2a45eb5a1d.png"},{"id":99238138,"identity":"adc146aa-eb99-4277-a818-ee6160fc1e37","added_by":"auto","created_at":"2025-12-30 13:55:07","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":226654,"visible":true,"origin":"","legend":"\u003cp\u003eParticipant screening and analysis flow with counts at each stage (assessed n=3,000; excluded n=2,778; included n=222).\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-8309904/v1/6f71f43531b486946a54ced7.png"},{"id":99788609,"identity":"513a683b-796b-4170-adb3-702bd9a7c53f","added_by":"auto","created_at":"2026-01-08 12:47:16","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":942941,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8309904/v1/68371ad0-8592-4f8e-85b6-6404492dd81d.pdf"},{"id":99238119,"identity":"9a89d1c4-ef3e-476e-98dd-a9a0b17ec884","added_by":"auto","created_at":"2025-12-30 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13:55:04","extension":"csv","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":158,"visible":true,"origin":"","legend":"","description":"","filename":"Table3.csv","url":"https://assets-eu.researchsquare.com/files/rs-8309904/v1/0ac559cce15643938f206643.csv"},{"id":99238133,"identity":"7d14c8ea-653b-44ef-ab66-9e9936e41b95","added_by":"auto","created_at":"2025-12-30 13:55:07","extension":"csv","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":186,"visible":true,"origin":"","legend":"","description":"","filename":"Table4.csv","url":"https://assets-eu.researchsquare.com/files/rs-8309904/v1/c55b0b91ddcb591758a5521f.csv"},{"id":99238121,"identity":"1016f876-e872-4772-a050-b54a18ca9992","added_by":"auto","created_at":"2025-12-30 13:55:05","extension":"docx","order_by":5,"title":"","display":"","copyAsset":false,"role":"supplement","size":37311,"visible":true,"origin":"","legend":"","description":"","filename":"Tables.docx","url":"https://assets-eu.researchsquare.com/files/rs-8309904/v1/d2a90a5e8134dac3953c8b34.docx"},{"id":99238129,"identity":"3221c507-6d31-4fc9-8265-0a8152a749fc","added_by":"auto","created_at":"2025-12-30 13:55:07","extension":"docx","order_by":6,"title":"","display":"","copyAsset":false,"role":"supplement","size":38658,"visible":true,"origin":"","legend":"","description":"","filename":"STROBEChecklist.docx","url":"https://assets-eu.researchsquare.com/files/rs-8309904/v1/74be7023f6b81eea1ffb97ac.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Comparison of Preformed Orthodontic Archwires with Modified Dental Arch Forms: A Cross-Sectional Study","fulltext":[{"header":"Background","content":"\u003cp\u003ePreservation of a patient\u0026rsquo;s original arch form is a cornerstone of orthodontic stability and periodontal safety. Recent evidence emphasizes that arch dimensions and shapes vary by sex and ancestry and are influenced by genetic and environmental factors. [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan additionalcitationids=\"CR22\" citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e] Preformed NiTi archwires\u0026mdash;engineered for favorable load‑deflection properties\u0026mdash;are widely employed during alignment and leveling, yet their standardized shapes do not necessarily reflect the diversity of natural arches. [\u003cspan additionalcitationids=\"CR4 CR5\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e] Multiple studies since 2020 have shown inconsistency between commercial archwire forms and clinical arch forms at key landmarks, especially at the canine level where standardized wires are commonly wider. [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] Moreover, the increasing adoption of digital workflows has improved the precision of arch form measurement and setup through three‑dimensional dental models. [\u003cspan additionalcitationids=\"CR9 CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan additionalcitationids=\"CR26\" citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eNiTi metallurgy has continued to evolve, including heat‑activated and copper‑NiTi variants; nevertheless, randomized trials demonstrate similar early alignment efficiency across many NiTi types, shifting clinical emphasis toward wire form rather than solely alloy subtype. [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan additionalcitationids=\"CR29 CR30\" citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e] Customized CAD/CAM appliances and robotic wire bending provide promising avenues for individualized archwire design, but preformed labial archwires remain dominant in daily practice. [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan additionalcitationids=\"CR33 CR34 CR35\" citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e] For clinicians operating in under‑represented populations, such as Yemeni adults, local normative data remain essential to reduce unnecessary transverse expansion, minimize periodontal risk, and support long‑term stability. [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e] This study reports population‑specific arch dimensions and predominant arch forms and benchmarks the fit of commonly used preformed NiTi archwires against a bracket‑point\u0026ndash;based reference graph.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy design and setting\u003c/h2\u003e \u003cp\u003eDesign: Cross‑sectional study using pretreatment casts from university clinics and private practices in Sana\u0026rsquo;a, Yemen, following STROBE. [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] Participants: 222 subjects aged 16\u0026ndash;28 years with permanent dentitions (excluding third molars), Angle Class I or II, no prior orthodontic treatment. Measurements: Clinical bracket points (CBPs) were used to compute Wc, Wm, Dc, Dm and proportional indices; arch forms were categorized (tapered, ovoid, square). Archwire benchmarking: Twenty‑seven 0.019\u0026times;0.025‑inch NiTi preformed archwires (11 manufacturers) were traced on a CBP reference grid with bracket‑base offsets; widths at L3 and L6 were compared to sample means. Statistics: Group comparisons by t‑tests/ANOVA; repeatability assessed by ICC, consistent with contemporary guidance. [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eSampling frame and sample size\u003c/h3\u003e\n\u003cp\u003eSampling frame and size: Records from two university clinics and three private orthodontic practices were screened. A priori, we targeted\u0026thinsp;\u0026ge;\u0026thinsp;200 subjects to estimate mean transverse widths within \u0026plusmn;\u0026thinsp;0.5 mm at 95% confidence, assuming SD\u0026thinsp;\u0026asymp;\u0026thinsp;3 mm based on pilot data and contemporary literature. This also provided \u0026ge;\u0026thinsp;80% power to detect sex‑related differences\u0026thinsp;\u0026ge;\u0026thinsp;1.5 mm in Wc and Wm using two‑sided α\u0026thinsp;=\u0026thinsp;0.05. Eligibility criteria mirrored everyday case mix to enhance external validity while excluding conditions that distort landmarks (e.g., large restorations encroaching on CBPs).\u003c/p\u003e\n\u003ch3\u003eParticipants and eligibility\u003c/h3\u003e\n\u003cp\u003eDesign: Cross‑sectional study using pretreatment casts from university clinics and private practices in Sana\u0026rsquo;a, Yemen, following STROBE. [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] Participants: 222 subjects aged 16\u0026ndash;28 years with permanent dentitions (excluding third molars), Angle Class I or II, no prior orthodontic treatment. Measurements: Clinical bracket points (CBPs) were used to compute Wc, Wm, Dc, Dm and proportional indices; arch forms were categorized (tapered, ovoid, square). Archwire benchmarking: Twenty‑seven 0.019\u0026times;0.025‑inch NiTi preformed archwires (11 manufacturers) were traced on a CBP reference grid with bracket‑base offsets; widths at L3 and L6 were compared to sample means. Statistics: Group comparisons by t‑tests/ANOVA; repeatability assessed by ICC, consistent with contemporary guidance. [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/p\u003e\n\u003ch3\u003eModel digitization and quality control\u003c/h3\u003e\n\u003cp\u003eModel digitization and quality control: Alginate impressions were poured within 30 minutes using vacuum‑mixed ISO Type 3 dental stone. Casts were scanned on a laboratory scanner with manufacturer‑specified trueness\u0026thinsp;\u0026le;\u0026thinsp;20 \u0026micro;m; STL files were inspected for holes and artifacts. The occlusal plane was standardized by three‑point orientation (incisal midpoint and mesiobuccal cusp tips of first molars) to minimize projection bias. Landmarks were placed on CBPs identified as the midpoint of the bracket footprint per crown, consistent with current digital measurement guidance. [\u003cspan additionalcitationids=\"CR9 CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/p\u003e\n\u003ch3\u003eLandmarks and measurements\u003c/h3\u003e\n\u003cp\u003eDesign: Cross‑sectional study using pretreatment casts from university clinics and private practices in Sana\u0026rsquo;a, Yemen, following STROBE. [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] Participants: 222 subjects aged 16\u0026ndash;28 years with permanent dentitions (excluding third molars), Angle Class I or II, no prior orthodontic treatment. Measurements: Clinical bracket points (CBPs) were used to compute Wc, Wm, Dc, Dm and proportional indices; arch forms were categorized (tapered, ovoid, square). Archwire benchmarking: Twenty‑seven 0.019\u0026times;0.025‑inch NiTi preformed archwires (11 manufacturers) were traced on a CBP reference grid with bracket‑base offsets; widths at L3 and L6 were compared to sample means. Statistics: Group comparisons by t‑tests/ANOVA; repeatability assessed by ICC, consistent with contemporary guidance. [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eReference grid construction: The CBP reference grid comprised a sixth‑order polynomial representation of the clinical archwire path with superimposed bracket‑base thickness offsets (0.4\u0026ndash;0.6 mm anterior, 0.6\u0026ndash;0.8 mm posterior) to better emulate the wire trajectory rather than the enamel surface. Widths at L3 and L6 were computed as chord lengths between left/right CBPs; depths were orthogonal distances from the midline to the chord lines. Proportional indices (WDc, WDm) were recorded to capture anterior vs posterior fullness independent of absolute size.\u003c/p\u003e \u003cp\u003e \u003cb\u003eReference grid and archwire evaluation\u003c/b\u003e \u003c/p\u003e \u003cp\u003eDesign: Cross‑sectional study using pretreatment casts from university clinics and private practices in Sana\u0026rsquo;a, Yemen, following STROBE. [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] Participants: 222 subjects aged 16\u0026ndash;28 years with permanent dentitions (excluding third molars), Angle Class I or II, no prior orthodontic treatment. Measurements: Clinical bracket points (CBPs) were used to compute Wc, Wm, Dc, Dm and proportional indices; arch forms were categorized (tapered, ovoid, square). Archwire benchmarking: Twenty‑seven 0.019\u0026times;0.025‑inch NiTi preformed archwires (11 manufacturers) were traced on a CBP reference grid with bracket‑base offsets; widths at L3 and L6 were compared to sample means. Statistics: Group comparisons by t‑tests/ANOVA; repeatability assessed by ICC, consistent with contemporary guidance. [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eReference grid construction: The CBP reference grid comprised a sixth‑order polynomial representation of the clinical archwire path with superimposed bracket‑base thickness offsets (0.4\u0026ndash;0.6 mm anterior, 0.6\u0026ndash;0.8 mm posterior) to better emulate the wire trajectory rather than the enamel surface. Widths at L3 and L6 were computed as chord lengths between left/right CBPs; depths were orthogonal distances from the midline to the chord lines. Proportional indices (WDc, WDm) were recorded to capture anterior vs posterior fullness independent of absolute size.\u003c/p\u003e \u003cp\u003eArchwire inventory: Eleven manufacturers were represented (e.g., 3M, Dentaurum, Ormco, American Orthodontics, Rocky Mountain Orthodontics, G\u0026amp;H, etc.). All wires were rectangular 0.019\u0026times;0.025‑inch NiTi intended for finishing/working arch stages to ensure cross‑brand comparability; when a line offered multiple shapes, the most clinically used tapered/ovoid forms were prioritized. Width measurements were performed at bracket‑position coordinates derived from average tooth dimensions to reflect clinically engaged segments. [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eArch form categorization\u003c/h2\u003e \u003cp\u003eArch form categorization: Following contemporary practice, arches were categorized into tapered, ovoid, or square based on an automated best‑fit to canonical templates using root‑mean‑square (RMS) error minimization, then visually verified by two calibrated examiners. Disagreements were resolved by consensus; Cohen\u0026rsquo;s κ was computed for interrater agreement on form categories.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eOutcomes\u003c/h3\u003e\n\u003cp\u003ePrimary outcomes were archwire\u0026ndash;arch width differences at L3 and L6 for maxillary and mandibular arches; secondary outcomes included arch‑form distribution and sex differences in transverse dimensions.\u003c/p\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eStatistical plan: Normality was assessed by Shapiro\u0026ndash;Wilk and homoscedasticity by Levene tests. Sex comparisons used independent‑samples t‑tests or Mann\u0026ndash;Whitney U as indicated; arch form distribution by sex used χ\u0026sup2; tests. For wire‑to‑arch comparisons, we summarized mean differences and their 95% CIs at L3 and L6 for each archwire model; one‑sample tests evaluated whether the mean difference deviated from 0 mm. Equivalence analyses used two one‑sided tests (TOST) with prespecified equivalence margins of \u0026plusmn;\u0026thinsp;1.0 mm at L3 and \u0026plusmn;\u0026thinsp;1.5 mm at L6, aligned with clinically acceptable bounds informed by contemporary orthodontic guidance. [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e] Multiplicity was addressed by Benjamini\u0026ndash;Hochberg FDR control (q\u0026thinsp;=\u0026thinsp;0.10) given the benchmarking nature of the analysis.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eReliability and repeatability\u003c/h2\u003e \u003cp\u003eRepeatability and reliability: Ten percent of casts were re‑landmarked and re‑measured after a two‑week washout period by the same examiner and by an independent examiner. We report ICC(2,1) for absolute agreement with 95% CIs for Wc, Wm, Dc, and Dm; Bland\u0026ndash;Altman plots confirmed absence of systematic bias. [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e] Category agreement for arch form used quadratic‑weighted κ and percent agreement; pre‑specified thresholds for acceptable reliability were ICC\u0026thinsp;\u0026ge;\u0026thinsp;0.90 and κ\u0026thinsp;\u0026ge;\u0026thinsp;0.80.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eSensitivity analyses\u003c/h2\u003e \u003cp\u003eSensitivity analyses: (1) Restriction to Class I subjects; (2) Stratification by sex; (3) Substitution of enamel‑based landmarks (FA points) for CBPs to evaluate robustness of width estimates. Results were directionally stable across sensitivity analyses (details available on request).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eEthics\u003c/h2\u003e \u003cp\u003eInstitutional approval and consent were obtained; full details are provided in Declarations.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eOvoid arch form predominated. Males showed larger transverse dimensions. Mean benchmarks: Maxilla Wc 35.92 mm, Wm 54.54 mm; Mandible Wc 28.37 mm, Wm 48.85 mm. Most preformed NiTi archwires exceeded natural canine widths; mean archwire\u0026ndash;arch differences were +\u0026thinsp;3.38 mm (maxillary L3), +\u0026thinsp;1.94 mm (maxillary L6), +\u0026thinsp;4.05 mm (mandibular L3), +\u0026thinsp;1.53 mm (mandibular L6). Best matches overall: 3M Ortho Form I (tapered), Dentaurum Arch Form I (tapered), Ormco Ortho Small.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eFindings align with recent literature reporting mismatch between commercial archwire geometries and clinical arch forms, notably at the canine level. [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] Given comparable alignment efficiency among NiTi subtypes, clinicians should prioritize wire form to preserve native arches, supplementing with individualized bends as needed. [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan additionalcitationids=\"CR29 CR30\" citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e] Digital measurement reliability is high, and customized appliances can realize target forms accurately, though posterior overcorrection may be necessary. [\u003cspan additionalcitationids=\"CR8 CR9 CR10 CR11\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan additionalcitationids=\"CR26\" citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e] For expansion therapies, predictability diminishes posteriorly and skeletal gains are unlikely; maintaining pretreatment intercanine width supports stability. [\u003cspan additionalcitationids=\"CR38 CR39 CR40\" citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e] Strengths include sample size and CBP‑based 3D measurements; limitations include regional product availability and reliance on mean fits.\u003c/p\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eComparison with contemporary literature\u003c/h2\u003e \u003cp\u003eOur findings echo contemporary bench and clinical evidence. Force‑mapping studies demonstrate that wire geometry materially influences force vectors along the arch; narrower anterior segments reduce proclination forces at L3 while broader posterior segments can increase expansion moments at L6. [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] Recent AJODO work measuring preformed wire dimensions at bracket positions confirms nontrivial inter‑brand variation and highlights that nominally similar \u0026lsquo;tapered\u0026rsquo; designs can diverge by several millimeters at key landmarks. [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] Systematic reviews on expansion with aligners and fixed appliances converge on higher predictability in premolar regions with diminishing returns posteriorly, aligning with our recommendation to avoid broad default forms without corroborating skeletal support. [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e] Furthermore, long‑term studies associate excessive increases in intermolar width with greater relapse risk, whereas conservative maintenance of intercanine width tends to enhance anterior stability. [\u003cspan additionalcitationids=\"CR40\" citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eCompared with studies from East Asian and European cohorts, the Yemeni sample displayed similar qualitative distribution of arch forms (ovoid predominance) but smaller absolute intercanine widths, particularly in the mandible. This suggests that wire catalogs configured around North American/European averages may require additional narrow, tapered options for Middle Eastern populations to minimize unintended expansion.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003ePopulation context and external validity\u003c/h2\u003e \u003cp\u003eThe Yemeni adult cohort reflects a typical university/private‑practice case mix in an urban setting. While our results may generalize to neighboring populations with shared ancestry and environmental exposures, clinicians should consider local anthropometric data wherever possible. Genetic‑environmental interactions in arch development are increasingly recognized; heritability estimates for arch dimensions are moderate, but habits, diet consistency, and respiratory patterns also contribute. [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e] Thus, the present normative values should be viewed as guidance to inform individualized selection rather than prescriptive targets.\u003c/p\u003e \u003cp\u003e \u003cb\u003ePractical workflow checklist for wire selection\u003c/b\u003e \u003c/p\u003e \u003cp\u003e1) Acquire calibrated digital models and standardize orientation; verify trueness and fill holes. [\u003cspan additionalcitationids=\"CR9 CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e] 2) Measure Wc/Wm and Dc/Dm at CBPs; categorize arch form against canonical templates (tapered, ovoid, square) and record sex and Angle class. 3) Screen manufacturer catalogs for the narrowest viable anterior dimension matching the patient\u0026rsquo;s Wc within \u0026plusmn;\u0026thinsp;1\u0026ndash;2 mm; prefer tapered forms when category is ambiguous. [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] 4) Evaluate posterior fit at L6; deviations up to ~\u0026thinsp;2 mm may be acceptable in healthy periodontium but reassess in thin buccal bone phenotypes. [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e] 5) If canine mismatch exceeds\u0026thinsp;~\u0026thinsp;3\u0026ndash;4 mm, add compensatory constriction bends or select a narrower archwire model; confirm incisor inclination targets to avoid iatrogenic proclination. 6) Reassess fit at finishing; introduce minor individualized bends rather than switching to broad forms that could undermine anterior stability. 7) Document measurements and rationale to support reproducibility and outcome auditing.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec18\" class=\"Section2\"\u003e \u003ch2\u003eData robustness and quality assurance\u003c/h2\u003e \u003cp\u003eWe adopted multiple safeguards to ensure data quality: laboratory scanning with high trueness, landmarking protocols aligned with digital reliability guidance, blinded repeat measurements, and pre‑registered equivalence bounds to discourage post‑hoc thresholding. Despite these safeguards, residual sources of imprecision include scanner stitching near interproximal contacts, CBP estimation on abraded enamel, and variations in bracket‑base thickness between products. However, the magnitude of observed wire‑arch mismatches (\u0026asymp;\u0026thinsp;3\u0026ndash;4 mm at L3) substantially exceeds plausible measurement error, strengthening the clinical signal.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec19\" class=\"Section2\"\u003e \u003ch2\u003eClinical implications\u003c/h2\u003e \u003cp\u003eArchwire selection should begin with an assessment of the patient\u0026rsquo;s baseline arch form and transverse dimensions on calibrated digital models. If a preformed wire exceeds native Wc by \u0026gt;\u0026thinsp;3 mm, clinicians should consider a narrower tapered option or introduce compensatory constriction bends anteriorly to avoid proclination and periodontal strain. Posteriorly, deviations\u0026thinsp;\u0026le;\u0026thinsp;2 mm at L6 are less likely to induce undesirable expansion, but caution is advised in reduced buccal bone thickness scenarios, where CBCT studies highlight potential dehiscence risk with broad forms. [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e] In aligner therapy or hybrid protocols, recent systematic reviews indicate expansion predictability decreases posteriorly and skeletal effects are minimal; therefore, broad targets must be tempered by biological constraints. [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eFor finishing phases using rectangular NiTi, minor customized bends can fine‑tune intercanine relationships while keeping overall wire geometry close to the patient\u0026rsquo;s pretreatment form. In practices with access to CAD/CAM or robotic wire‑bending, customized geometries can be derived directly from CBPs and verified with force‑mapping to ensure biologically sound loading. [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan additionalcitationids=\"CR33 CR34\" citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec20\" class=\"Section2\"\u003e \u003ch2\u003eLimitations and future research\u003c/h2\u003e \u003cp\u003eThe benchmarking approach used mean arch values, which may obscure subject‑level mismatches; future work should conduct case‑matched wire fitting and prospectively evaluate periodontal and stability outcomes. Bracket prescription and wire slot size can alter the effective archwire path; although bracket‑base offsets were modeled, true in‑vivo trajectories may vary with adhesive thickness and torque play. The archwire portfolio reflects commonly available products in the study region; inclusion of additional global products could refine generalizability. Finally, while CBCT evidence suggests caution with buccal expansion in thin biotypes, direct imaging was beyond scope here. Randomized clinical trials that compare preformed vs customized archwire geometry with hard/soft tissue endpoints would be informative.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec21\" class=\"Section2\"\u003e \u003ch2\u003eConcluding clinical recommendations\u003c/h2\u003e \u003cp\u003eIn daily practice, selecting a preformed archwire that respects native transverse dimensions is both feasible and impactful. For adult Yemeni patients similar to those studied here, we advise: (a) begin with a tapered archwire whose anterior width is within ~\u0026thinsp;1\u0026ndash;2 mm of the patient\u0026rsquo;s measured Wc; (b) avoid broad, square forms unless dentoalveolar expansion is specifically indicated and biologically supported; (c) verify posterior fit at L6 and limit default expansion to \u0026le;\u0026thinsp;2 mm in the absence of skeletal support; (d) leverage finishing bends to individualize rather than swapping to substantially broader stock forms; and (e) document measurements, chosen wire geometry, and rationale. These simple steps, grounded in 2020\u0026ndash;2025 evidence and enabled by accessible digital tools, can help reduce iatrogenic proclination, preserve periodontal health, and support durable, esthetic outcomes.\u003c/p\u003e \u003cp\u003eFinally, beyond the specific product matches identified herein, the overarching message is conceptual: preformed archwires should be treated as templates to be critically appraised against each patient\u0026rsquo;s anatomy rather than default trajectories. As digital orthodontics matures, routine integration of standardized CBP‑based measurements, transparent reliability reporting, and explicit equivalence margins in comparative evaluations will foster higher quality evidence and more consistent care. We encourage researchers to publish open measurement datasets and wire geometries to accelerate cumulative progress and enable independent replication.\u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusions","content":"\u003cp\u003ePreformed NiTi archwires frequently over‑expand canine widths in Yemeni adults. Selecting narrower preformed forms at L3 and slightly narrower at L6 can better preserve individual arch forms. No single product matched all metrics; individualized adjustments remain necessary.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eEthics approval and consent to participate: Approved by the University of Science and Technology Medical Ethical Committee (Sana\u0026rsquo;a, Yemen); written informed consent was obtained from all participants. Approval reference number: (EAC/UST172).\u003c/p\u003e\n\u003cp\u003eAvailability of data and materials: De‑identified data, archwire measurements, and analysis scripts are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003eConsent for publication: Not applicable (no identifiable individual data are included).\u003c/p\u003e\n\u003cp\u003eCompeting interests: None declared.\u003c/p\u003e\n\u003cp\u003eFunding: None.\u003c/p\u003e\n\u003cp\u003eAuthors\u0026rsquo; contributions: Conceptualization FJ; RI; methodology, FJ; ML; RI; software, FJ and RI; formal analysis, SH and FJ; investigation, SH; and KD; data curation, SA; and RI; writing original draft preparation SH and RI; writing, review and editing SH and KD; supervision RI and ML; funding acquisition, SH; administration: SH. All authors have read and agreed to the published version of the manuscript.\u003c/p\u003e\n\u003cp\u003eTables 1\u0026ndash;4 are provided as a separate DOCX and CSV files to match BMC submission preferences.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eMa J, et al. Clinical outcomes of Invisalign therapy in arch expansion: a systematic review. BMC Oral Health. 2023;23:302. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1186/s12903-023-03302-6\u003c/span\u003e\u003cspan address=\"10.1186/s12903-023-03302-6\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGiri J, et al. Heritability of dental arches and occlusal characteristics: a systematic review and meta\u0026ndash;analysis. 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Research article\u0026mdash;Instructions for Authors. 2025. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://link.springer.com/journal/12903/submission-guidelines/research-article\u003c/span\u003e\u003cspan address=\"https://link.springer.com/journal/12903/submission-guidelines/research-article\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBMC Oral Health. Submission guidelines. 2025. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://link.springer.com/journal/12903/submission-guidelines\u003c/span\u003e\u003cspan address=\"https://link.springer.com/journal/12903/submission-guidelines\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBioMed Central. Structuring your manuscript. 2025. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.biomedcentral.com/getpublished/writing-resources/structuring-your-manuscript\u003c/span\u003e\u003cspan address=\"https://www.biomedcentral.com/getpublished/writing-resources/structuring-your-manuscript\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBritish Orthodontic Society. Records: collection and management guidelines for digital models. 2022. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://bos.org.uk/professionals-members/advice-sheets-and-guidelines/\u003c/span\u003e\u003cspan address=\"https://bos.org.uk/professionals-members/advice-sheets-and-guidelines/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTable 1 to 4 are available in the Supplementary Files section.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"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":"bmc-oral-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ohea","sideBox":"Learn more about [BMC Oral Health](http://bmcoralhealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ohea/default.aspx","title":"BMC Oral Health","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"arch form, preformed archwires, nickel–titanium, intercanine width, intermolar width, Yemeni population, bracket points","lastPublishedDoi":"10.21203/rs.3.rs-8309904/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8309904/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eSelecting an archwire that respects a patient\u0026rsquo;s native arch form is central to stability and periodontal safety. Evidence from the last five years shows substantial heterogeneity in arch dimensions across populations, with contemporary preformed nickel\u0026ndash;titanium (NiTi) archwires often wider than natural arches at the canine level. [\u003cspan additionalcitationids=\"CR2 CR3 CR4 CR5\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e] This study quantified Yemeni adult arch dimensions and predominant arch forms and compared them with commonly used preformed NiTi archwires using a bracket‑point\u0026ndash;based reference graph.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eIn this cross‑sectional analysis, pretreatment casts from 222 subjects (Class I and II; 16\u0026ndash;28 years) were digitized. Clinical bracket points defined transverse widths (intercanine, Wc; intermolar, Wm) and depths (Dc, Dm). Arch form was categorized as tapered, ovoid, or square. Twenty‑seven rectangular 0.019\u0026times;0.025‑inch NiTi archwires from 11 manufacturers were traced on a CBP reference grid that incorporated bracket‑base offsets. Archwire widths at the canine (L3) and first‑molar (L6) levels were compared with sample means. Repeatability was assessed on a subsample. [\u003cspan additionalcitationids=\"CR8 CR9 CR10 CR11 CR12\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eOvoid was the predominant arch form followed by tapered and square. Males exhibited larger transverse dimensions than females. Across brands, most preformed NiTi archwires were wider than natural arches at the canine level. Mean (archwire \u0026ndash; arch) differences were approximately\u0026thinsp;+\u0026thinsp;3.4 mm at maxillary canines and +\u0026thinsp;1.9 mm at maxillary first molars; in the mandible, +\u0026thinsp;4.1 mm at canines and +\u0026thinsp;1.5 mm at first molars. Closest overall matches were 3M Ortho Form I (tapered), Dentaurum Arch Form I (tapered), and Ormco Ortho Small. [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan additionalcitationids=\"CR15 CR16 CR17\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eNo single preformed archwire matched the Yemeni adult sample across arches and landmarks. Clinical selection should bias toward archwires\u0026thinsp;\u0026asymp;\u0026thinsp;3\u0026ndash;4 mm narrower at canines and \u0026asymp;\u0026thinsp;2 mm narrower at first molars to preserve patient‑specific arch forms, with individualized adjustments where needed. Reporting followed STROBE. [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/p\u003e","manuscriptTitle":"Comparison of Preformed Orthodontic Archwires with Modified Dental Arch Forms: A Cross-Sectional Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-30 13:53:56","doi":"10.21203/rs.3.rs-8309904/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-01-27T10:36:25+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-12T13:46:45+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-12T13:31:00+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"49732701462758811696730371835513953079","date":"2026-01-09T11:54:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"115096548796833001869159402531072586278","date":"2026-01-05T22:09:53+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"298584796539818954559821180877011262252","date":"2026-01-02T13:36:14+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-12-31T07:24:01+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-12-10T05:51:12+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-12-09T04:29:58+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-12-09T04:29:56+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Oral Health","date":"2025-12-08T16:44:00+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-oral-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ohea","sideBox":"Learn more about [BMC Oral Health](http://bmcoralhealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ohea/default.aspx","title":"BMC Oral Health","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"7dcea1dc-ce91-422f-beb1-15dac1fd91da","owner":[],"postedDate":"December 30th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-04-15T06:08:49+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-30 13:53:56","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8309904","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8309904","identity":"rs-8309904","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}