Search Results (1,629)

Objectives: The aim of the present systematic review and meta-analysis is to compare bracket adhesion failure rates between resin-modified glass ionomer cement (RMGIC) and conventional resin adhesives (CRA) during fixed orthodontic treatment (OT), based on evidence from randomized controlled trials (RCTs). Methods: The research question is “Is there a difference in bracket adhesion failure rates between RMGIC and CRA?” The study was performed in accordance with the PRISMA guidelines. A comprehensive literature search was performed across multiple databases without time or language restrictions through February 2026. Keywords were used in different combinations using Boolean operators. Hand searching was performed and disagreements were resolved via discussion. The risk of bias (RoB) and certainty of evidence (CoE) were assessed using the Cochrane risk of bias tool and Grading of Recommendations Assessment, Development and Evaluation approach, respectively. Quantitative data synthesis was conducted using a random-effects model to calculate pooled odds ratios and 95% confidence intervals. Results: Seven RCTs met the inclusion criteria. Bracket failure rates ranged from 5.95% to 15.0% for RMGIC and 3.4% to 25.0% for CRA. The pooled meta-analysis revealed no statistically significant difference in bracket failure between the two adhesive types (OR = 1.00; 95% CI: 0.60 to 1.67), although substantial statistical heterogeneity was observed (I² = 69.0%, p = 0.0065). One included trial demonstrated significantly improved retention for RMGIC when combined with a specific enamel deproteinization conditioning step prior to bonding. Three studies had a low RoB and the remaining were judged as having “some concerns”. The overall CoE was low. Conclusions: Based on the currently available randomized evidence, no statistically significant difference in bracket adhesion failure rates was observed between RMGIC and CRA during fixed OT. However, given the low CoE, substantial heterogeneity among studies, and relatively short follow-up periods, these findings should be interpreted with caution. Further well-designed randomized controlled trials with longer follow-up are needed to provide more definitive conclusions. Full article

Objectives: This study aimed to evaluate and compare the cost-effectiveness of the surgery-first and orthodontic-first approaches in Thai patients with dentofacial deformities undergoing orthognathic surgery. Methods: This retrospective cohort study included 30 patients with dentofacial deformities, divided into the surgery-first approach (SFA, n = 15) and orthodontic-first approach (OFA, n = 15). All underwent double-jaw surgery without genioplasty performed by a single surgeon and orthodontist. Data collected included operative and orthodontic costs, operative time, total treatment and hospital costs, treatment duration, and length of hospital stay. Cost-effectiveness was assessed using the incremental cost-effectiveness ratio (ICER) and incremental time-effectiveness ratio (ITER), with effectiveness measured by quality of life via the Thai Orthognathic Quality of Life Questionnaire (OQLQ) before and at the time of debonding the orthodontic appliance. Results: Overall, the SFA demonstrated greater cost-effectiveness than the OFA. However, the SFA group incurred slightly higher hospital costs. There were no statistically significant differences between the two groups in operative cost, hospital cost, total cost, operative time, or length of hospital stay (p > 0.05). By contrast, orthodontic cost, orthodontic treatment duration, and total treatment duration were significantly lower in the SFA group compared with the OFA group (p < 0.05). Conclusions: Within limits, the SFA is a potentially beneficial alternative to OFA. Patients and clinicians may benefit from using SFA by experiencing shorter treatment duration, lower orthodontic treatment costs, and improvements in certain aspects of quality of life. Further studies with larger sample sizes and longitudinal data are necessary to establish the long-term effectiveness. Full article

Accurate tooth segmentation plays a crucial role in computer-aided dental diagnosis and treatment planning, particularly in applications such as tooth detection, lesion localization, orthodontic analysis, and implant surgery. However, panoramic dental X-ray images often suffer from tooth adhesion, low contrast, and blurred boundaries, making precise delineation difficult and potentially compromising downstream clinical analysis. To address these challenges, we propose a boundary-aware segmentation framework, termed Boundary-Aware ResU-Net (BA-ResUNet), which is built upon a ResU-Net backbone and enhanced with Coordinate Attention (CA) and explicit boundary modeling mechanisms. Specifically, CA modules are introduced into the encoder to improve spatial representation and positional awareness. In addition, a Boundary Extraction Module (BEM) is designed to capture boundary priors from shallow and deep features, while a Boundary Injection Module (BIM) progressively incorporates these cues into the decoder through foreground enhancement and background suppression. This design enables the network to better preserve inter-tooth gaps and improve boundary delineation. Experiments on the MICCAI STS-2D dental dataset demonstrate that the proposed method achieves superior performance in terms of Dice and IoU compared with representative existing methods. Ablation and qualitative analyses further show that CA and BEM/BIM play synergistic roles in improving regional overlap and boundary localization, particularly in challenging cases involving adhesion, low contrast, and indistinct contours. These results indicate that the proposed framework provides a reliable and effective solution for panoramic tooth segmentation and has promising potential for computer-aided dental applications. Full article

Objectives: A comprehensive diagnosis and treatment were carried out in 104 newborns, including 48 children diagnosed with unilateral cleft lip and palate (UCLP) and 56 patients diagnosed with bilateral cleft lip and palate (BCLP). The control group consisted of 116 medical records and diagnostic models of jaws from newborns with UCLP/BCLP, which were analysed before and after orthodontic correction using a removable facebow with headgear attachment. Methods: All newborns (n = 104) underwent orthodontic correction to reposition of the alveolar process fragments in UCLP and intermaxillary bone in BCLP using mini-implants and elastic traction devices/springs, followed by primary cheiloplasty. Cheiloplasty was performed one month after fragment alignment had been achieved. Results: Statistical analysis showed that orthodontic correction using mini-implants and elastic traction was highly effective. In the UCLP group, normalised alignment of alveolar fragments was achieved in 97.9% of cases (p = 0.0000000016); in the BCLP group, normalised positioning of the intermaxillary bone was observed in 96.42% (p = 0.00000000007). A direct comparison between the treatment and control groups revealed consistent significance across all diastasis measurements, supporting the clinical advantage of fixed orthodontic approaches. Conclusions: The clinical data and statistical analysis indicate that the fixed orthodontic appliance combined with mini-implants and elastic traction is effective. This approach normalises alveolar and intermaxillary positioning and provides optimal preoperative conditions for primary cheiloplasty and subsequent uranoplasty. It also shortens rehabilitation duration and leads to stable aesthetic and functional results. Full article

Objectives: Oral hygiene maintenance may be influenced by both malocclusion severity and orthodontic appliance type during early orthodontic treatment. Therefore, this study aimed to evaluate the relationship between orthodontic treatment need assessed using the Index of Orthodontic Treatment Need (IOTN) and oral hygiene status measured using the Simplified Oral Hygiene Index (OHI-S) in children undergoing early orthodontic treatment and to compare short-term oral hygiene outcomes between clear aligner and removable appliance therapies. Methods: Twenty-four children aged 6–12 years with anterior dental crossbite were included in this prospective observational cohort study. Patients treated with clear aligners (n = 12) or removable appliances (n = 12) were evaluated. Orthodontic treatment need was assessed using the IOTN Dental Health Component (DHC) and Aesthetic Component (AC), and oral hygiene status was evaluated using the OHI-S at baseline and day 14. Statistical analyses were performed with p < 0.05 considered significant. Results: A statistically significant positive correlation was observed between IOTN-DHC and IOTN-AC scores (rs = 0.648; p = 0.001). Participants with higher orthodontic treatment need had poorer oral hygiene status at baseline, and this difference remained evident at day 14. Day-14 OHI-S scores were significantly higher in the removable appliance group than in the clear aligner group (p = 0.039). In addition, the reduction in OHI-S scores was significantly greater in the clear aligner group (p = 0.043). When all participants were analyzed together, oral hygiene status improved significantly from baseline to day 14 (p < 0.001). Conclusions: Higher orthodontic treatment need was associated with poorer oral hygiene status during early orthodontic treatment. Clear aligners were associated with more favorable short-term oral hygiene outcomes than removable appliances. Full article

Orthodontic tooth movement (OTM) is a biologically driven process resulting from the mechanically induced remodeling of the periodontal ligament (PDL) and alveolar bone. A marked inter-individual variability exists in the rate of tooth movement, susceptibility to adverse outcomes such as external apical root resorption (EARR), and overall treatment response. This narrative review synthesizes current evidence on molecular, genetic, and epigenetic biomarkers that underline these differences. We summarize established local biomarkers derived from gingival crevicular fluid and saliva, including inflammatory cytokines, matrix metalloproteinases, and bone remodeling mediators reflecting OTM compression- and tension-side biology. Beyond fluid biomarkers, growing attention is given to genetic and epigenetic determinants of OTM. Specific gene mutations are associated with impaired or absent tooth movement, while multiple single-nucleotide polymorphisms have been linked to increased risk of EARR. Recent studies further demonstrate that orthodontic forces induce epigenetic remodeling in PDL cells, including DNA methylation changes in the gene promoters, histone modifications, and force-responsive non-coding RNAs such as miR-21 and miR-146a, which collectively regulate osteoclastogenesis, inflammation, and tissue adaptation. These findings indicate that OTM is governed by an integrated network combining mechanical stimuli with genetic predisposition and dynamic epigenetic regulation. Understanding these mechanisms provides a foundation for the development of biomarker-guided, patient-specific therapeutic strategies. Full article

Bayesian estimation of nonlinear mixed-effects models typically relies on Markov-Chain Monte Carlo (MCMC) methods due to the intractability of the posterior distribution. While widely used for longitudinal data with missing observations, the performance of MCMC algorithms is often taken for granted, despite their critical impact on inference quality. This paper investigates MCMC-based estimation for Bayesian nonlinear mixed-effects models with missing data, focusing on convergence behavior and computational efficiency. We propose a hybrid sampling framework that combines Gibbs sampling with Metropolis–Hastings (MH) and adaptive MH algorithms to improve mixing and stability. Convergence diagnostics, the effective sample size, and computational performance are systematically evaluated. Simulation studies assess the effects of the iteration length, burn-in proportion, and sample size, and the methodology is illustrated using orthodontic growth data and the Treatment of Lead-Exposed Children (TLC) trial. Full article

Background and Objectives: Maintenance of condylar position during bilateral sagittal split ramus osteotomy (BSSRO) is important for preserving temporomandibular joint biomechanics and skeletal stability. During surgery, loss of muscle tone under general anesthesia may alter the condyle–fossa relationship, making accurate repositioning of the proximal segment challenging. Although manual positioning remains the most commonly used intraoperative approach, evidence regarding its ability to preserve the preoperative condyle–fossa relationship remains limited. This study evaluated changes in the condyle–fossa relationship following BSSRO performed with manual proximal segment positioning. Materials and Methods: This single-center retrospective study included lateral cephalometric radiographs of 14 patients (8 females, 6 males; aged 19–29 years) with skeletal Class III malocclusion treated with combined orthodontic treatment and BSSRO. Radiographs were obtained preoperatively (T0), immediately postoperatively (T1), and at the final follow-up examination (T2). Condylar position was assessed using a Cartesian coordinate system, joint space measurements, and the Condyle Position Index (CPI). Statistical analyses were performed using the Friedman and Wilcoxon signed-rank tests (p < 0.05). Results: Significant differences were observed in CPI and anterior joint space measurements across the observation periods. Interval analysis demonstrated increased CPI values and decreased anterior joint space measurements between T1 and T2, whereas no significant immediate postoperative changes were observed. Intra-observer reliability was excellent, with intraclass correlation coefficients exceeding 0.90 for all variables. Conclusions: Manual positioning of the proximal segment during BSSRO may provide acceptable immediate postoperative condyle–fossa stability but may not completely maintain the preoperative condyle–fossa relationship over time. Although no significant immediate postoperative changes were observed, significant changes in the condyle–fossa relationship were identified at the final follow-up examination. These findings support the need for further prospective studies incorporating clinical temporomandibular joint assessment and three-dimensional imaging. Full article

To evaluate the effects of three different 3D printers, two clear aligner resins, two specimen thicknesses, two lengths, and two geometric designs on the tensile strength and elastic modulus of directly printed clear aligners. Specimens were produced from two orthodontic aligner resins, Clear A (Senertek, Izmir, Turkey) and Tera Harz TA 28 (Graphy Inc., Seoul, Republic of Korea), using three different 3D printers: Ackuretta SOL (LCD), Asiga MAX (DLP), and UNIZ NBEE (LCD). Specimens were designed in two forms (dumbbell, in accordance with ISO 527 3, and flat strip), in two thicknesses (0.5 mm and 1 mm), and in two lengths (short and long), yielding 24 groups with 5 specimens each (n = 120). All specimens were post processed using the Tera Harz Spinner and cured for 25 min under nitrogen atmosphere in the THC 2 MC unit, followed by a 1 min boiling water treatment. Tensile tests were performed on a universal testing machine (Shimadzu Corp., Kyoto, Japan) up to fracture. Maximum force (N) and elastic modulus (N/mm²) were recorded. Data were analyzed using Kruskal–Wallis, Mann–Whitney U, and Aligned Rank Transform ANOVA tests with Dunn post hoc and Bonferroni correction (p < 0.05). Printer type had no significant effect on maximum force (p = 0.357) or elastic modulus (p = 0.052). Resin type (p < 0.001), thickness (p < 0.001), and specimen geometry (p < 0.001) showed significant effects on both parameters. TA 28 specimens exhibited higher mechanical performance than Clear A. Increased thickness produced higher maximum force and elastic modulus values. Flat geometries showed the highest maximum force, while the short dumbbell exhibited the lowest. The long thin dumbbell geometry yielded the highest elastic modulus values. Resin composition, thickness, and specimen geometry are the primary determinants of mechanical performance in directly printed clear aligners, whereas printer type appears to play a limited role. Full article

Artificial intelligence (AI) has transformed orthodontic diagnosis, yet its application to orthodontic materials science remains critically underexplored. This perspective identifies and characterizes the AI–materials integration gap as the central unresolved problem in digital orthodontics: AI-optimized treatment plans are currently executed through empirically selected materials whose mechanical behavior is never modeled by the planning system. We examine four domains where this gap is consequential: thermoplastic aligner polymers (PETG vs. TPU), where supervised ANNs can predict force decay from polymer composition; NiTi archwire alloys, where Bayesian optimization and Gaussian process regression are accelerating alloy design; additive manufacturing of orthodontic devices, where supervised ML reduced print-parameter optimization burden in a 2025 five-variable surface roughness study; and AI-driven biological response prediction, where FEA-surrogate neural networks reduced biomechanical computation from minutes to milliseconds per patient query. A scoping review of clear aligner AI identified 41 studies—none addressing aligner material properties as a primary outcome. We argue that closing the AI–materials gap requires standardized open material-performance datasets; FEA-surrogate models integrating polymer stiffness as a treatment-planning input; patient-specific digital twins with defined material, mechanical, and biological parameter layers; and federated learning infrastructure spanning clinics and manufacturers. Full article

Background and Objectives: Halitosis is a prevalent oral concern that meaningfully affects oral health-related quality of life (OHRQoL), yet how active dental treatment is associated with short-term changes in the objective–subjective halitosis–QoL nexus remains poorly quantified. Interpretation is complicated by the multifactorial nature of malodor and by baseline differences between patients selected for different dental procedures. We compared changes in volatile sulfur compound (VSC) emissions, organoleptic ratings, tongue-coating burden, and OHIP-14 across three contrasting treatment modalities and explored whether VSC change statistically accounted for OHRQoL change. Methods: In a non-randomized prospective comparative study, 119 adults (18–67 y) commencing one of three procedures were assessed at baseline and at 8 weeks: scaling and root planing (Group A, n = 42), fixed prosthodontic rehabilitation (Group B, n = 38), or fixed orthodontic appliance bonding (Group C, n = 39). Outcomes included Halimeter^® VSC (ppb), Rosenberg organoleptic score (0–5), Winkel tongue-coating index (TCI), self-perceived halitosis, and OHIP-14 total and seven-domain scores. Mixed-design ANOVA, ANCOVA, prespecified multivariable regression, mediation (5000 bootstrap resamples), receiver operating characteristic analysis, and four-class latent class analysis were performed. A sensitivity-analysis framework including expanded covariate adjustment, propensity-score overlap weighting, and baseline-severity strata was also applied to address residual baseline imbalance. Secondary mediation, ROC, and latent-class analyses were considered exploratory. Results: At 8 weeks, VSCs fell by 116.4 ± 38.7 ppb in Group A and 35.4 ± 29.1 ppb in Group B but rose by 34.3 ± 28.6 ppb in Group C (p < 0.001). OHIP-14 improved by 10.3 and 4.9 points in A and B and worsened by 3.7 in C (p < 0.001). ΔVSC correlated with ΔOHIP-14 (ρ = 0.51, p < 0.001) and most strongly with the psychological discomfort domain (ρ = 0.58). VSC change mediated 35.1% of the periodontal-versus-orthodontic association on QoL (indirect β = −4.7; 95% CI −6.3 to −3.1). Because VSC and OHIP-14 changes were measured over the same interval, mediation was interpreted cautiously. A ΔVSC threshold of −63 ppb predicted clinically meaningful OHIP-14 improvement (AUC = 0.81). Latent class analysis identified four distinct responder phenotypes. The cutoff and responder classes were internally derived and require external validation. Sensitivity analyses preserved the direction of the primary contrasts, but residual confounding remains possible. Conclusions: Treatment modality was associated with the direction and magnitude of halitosis and QoL change, with orthodontic patients constituting a vulnerable subgroup. Targeted oral-hygiene reinforcement during fixed-appliance therapy is warranted. Full article

Tooth extraction and maximum anchorage assessment are key decision points in orthodontic treatment planning, yet existing machine learning models for orthodontic decision support often lack transparency, limiting their clinical interpretability and trustworthiness. In this study, we developed and externally validated an explainable orthodontic treatment decision-support model that integrates expert-derived Analytic Hierarchy Process (AHP) weighting with machine learning. A diagnostic indicator framework comprising 18 orthodontic variables was established through a literature review, clinical data analysis, and two rounds of expert surveys. A retrospective cohort of 485 patients receiving fixed-appliance orthodontic treatment was used for model development and internal validation. AHP-derived composite scores were incorporated into the machine learning models for two prediction tasks, namely tooth extraction and maximum anchorage requirement, and an expert-informed fuzzy-rule score was calculated from pretreatment indicators for the maximum anchorage task to capture clinically interpretable anchorage tendencies. Model performance was evaluated using ROC-AUC, F1 score, precision, recall, PR-AUC, calibration analysis, and decision curve analysis, while SHAP was applied to interpret feature contributions. The AHP-RF extraction model and AHP-enhanced LR maximum anchorage model achieved the highest AUCs among the compared models (0.864 and 0.822, respectively), although paired DeLong tests showed no significant differences from the closest competing models. SHAP analysis identified lower lip-to-E-line distance, U1-NA, and the AHP composite score as important predictors, indicating consistency between model outputs and clinical reasoning. In the external validation cohort, the extraction model correctly classified 57 of 74 cases, and the maximum anchorage model correctly classified 24 of 29 cases, supporting the preliminary transportability of the proposed framework. These results suggest that integrating AHP-derived expert knowledge with machine learning provides an explainable and clinically interpretable decision-support model for orthodontic treatment planning, with potential value in improving standardized, evidence-informed, and patient-specific orthodontic decision-making. Full article

Background/Objectives: Orthodontic treatment induces controlled mechanical forces that alter the periodontal environment, including changes in oral microbiota composition and activation of local inflammatory pathways. Despite the widespread and growing use of orthodontic appliances across all age groups, the magnitude, timing, and multi-domain biological impact of these changes have not been comprehensively quantified in a single systematic synthesis. This systematic review and meta-analysis aimed to synthesize the available evidence on periodontal clinical parameters, oral microbiota composition, and local inflammatory biomarkers associated with orthodontic treatment using fixed appliances and clear aligners, and to provide a structured, GRADE-rated evidence base for clinical practice. Methods: A systematic review and meta-analysis was conducted in accordance with PRISMA 2020 guidelines. PubMed/MEDLINE, Scopus, and Web of Science were searched from inception to March 2026. Prospective cohort studies, longitudinal clinical studies, and randomized controlled trials evaluating periodontal parameters, oral microbiota, and inflammatory biomarkers during orthodontic treatment were included. Quantitative synthesis was performed using mean differences or standardized mean differences with 95% confidence intervals, primarily assessing within-group (pre–post) changes. Results: Eighteen studies (n = 812 patients; follow-up 3–12 months) met inclusion criteria. Fixed orthodontic appliances were consistently associated with transient increases in plaque index (MD 0.45, 95% CI 0.32–0.58; I² = 62%), gingival index (MD 0.38, 95% CI 0.25–0.51; I² = 55%), and bleeding on probing (MD 15.2%, 95% CI 10.1–20.3%; I² = 48%), particularly during early treatment phases. Microbiological analyses demonstrated within-group shifts toward increased prevalence of periodontopathogenic species (Streptococcus mutans OR 2.45, 95% CI 1.89–3.18; Porphyromonas spp. OR 2.14, 95% CI 1.67–2.75) in patients treated with fixed appliances. Local inflammatory responses were characterized by elevated IL-1β (MD 1.2, 95% CI 0.8–1.6) and IL-6 (MD 0.9, 95% CI 0.6–1.2) in gingival crevicular fluid. Certainty of evidence was rated moderate for plaque and gingival indices and low for microbiological and inflammatory outcomes (GRADE). Conclusions: Orthodontic treatment—particularly with fixed appliances—is associated with transient, reversible deterioration of periodontal indices, shifts toward a more dysbiotic oral microbiome, and elevation of local inflammatory mediators in gingival crevicular fluid during active treatment phases. These changes are manageable through structured preventive protocols and regular periodontal monitoring. Future prospective studies with concurrent control groups and standardized multi-domain outcome measures are needed to better define the magnitude and reversibility of these biological responses. PROSPERO: CRD420261336117. Full article

Background/Objectives: Cephalometric analysis is essential in orthodontics and for studying conditions such as obstructive sleep apnea syndrome (OSAS). However, manually identifying anatomical landmarks and segmenting the pharyngeal airway on lateral cephalograms can be time-consuming and prone to errors. This study evaluates the CEPH_2D system, an AI-based tool designed to automate cephalometric landmark detection and pharyngeal airway segmentation from 2D lateral cephalometric radiographs. Methods: The system was evaluated on 35 anonymized lateral cephalograms obtained from patients aged 6–65 years, including mixed and permanent dentition cases. Two experienced clinicians generated and reviewed the ground truth annotations for cephalometric landmark localization and pharyngeal airway segmentation. System performance was assessed using mean radial error (MRE), successful detection rate (SDR), mean average precision (mAP), Dice similarity coefficient (DSC), precision, recall, and inference time. Results were compared with manual methods and existing automated tools. Results: The system reached a mean radial error (MRE) of 0.740 ± 0.793 mm for the key point detection task and a mean Dice Score (mDSC) of 0.935 ± 0.040 with an average processing time of 2.557 ± 0.504 s. Conclusions: CEPH_2D appears to be a promising adjunctive tool for automatic cephalometric landmark detection and pharyngeal airway segmentation on lateral cephalograms, although clinician verification remains advisable before clinical interpretation or treatment planning, particularly for landmarks showing higher detection errors. Full article

Background/Objectives: Changes in the mechanical behavior of orthodontic archwires during clinical use are not fully understood, particularly when different bracket systems are employed. Self-ligating (SL) brackets have gained considerable popularity in orthodontic practice in recent years, largely due to claims of improved treatment efficiency and biomechanical performance. Nevertheless, current evidence has not consistently demonstrated statistically significant differences between conventional ligation (CL) brackets and SL systems. The aim of this study was to evaluate changes in the mechanical properties and degradation over time of nickel-titanium (NiTi) archwires after clinical use in orthodontic treatments performed with CL and SL brackets. Methods: A comparative study was conducted using archwires retrieved from orthodontic patients. Round 0.014-inch NiTi wires (GC Orthodontics America Inc., IL, USA) were analyzed. The archwires were used in 60 patients treated with either CL or SL appliances and evaluated at four time points: before clinical use (T0), and after 1 month (T1), 2 months (T2), and 3 months (T3) of intraoral service. Mechanical testing was performed according to ISO 15841:2014 + Amd. 1:2020 using a three-point bending test with a universal testing machine (Z005 Test Control II Universal Testing Machine, Zwick Roell, Kennesaw, GA, USA). The variables analyzed included the mean force delivered by the archwires at deflections of 3 mm (F3), 2 mm (F2), 1 mm (F1), and 0.5 mm (F0.5), as well as the slope of the superelastic plateau at 2 mm, 1 mm, and 0.5 mm. The static and dynamic friction coefficients, as well as the friction forces associated with the wires and the two types of brackets, were determined using a modified MTS-Bionix servo-hydraulic testing machine. The tests were conducted at 37 °C in a saline environment. Results: Both groups showed changes in the superelastic behavior of NiTi archwires. Alterations increased with longer intraoral exposure. In the SL group, significant modifications were already observed after one month of clinical use, with a reduction in the force delivered and a loss of superelastic characteristics. These changes remained relatively stable thereafter, with no statistically significant differences during the following months. In contrast, the CL group showed a progressive reduction in force delivery and superelasticity over time. This is due to the difference in friction between the wire and the CL bracket compared to the SL bracket, which results in greater force transfer for tooth movement. Conclusions: Overall, differences in the mechanical behavior of archwires between CL and SL systems were observed during the initial stages of clinical use. However, these differences diminished over time, and no significant differences were detected after three months. Considering the progressive degradation of mechanical properties, the reuse of archwires that have remained intraorally for more than three months may not be advisable. Full article