Multiparametric performance comparison of dental composites for clear aligner attachments

Multiparametric performance comparison of dental composites for clear aligner attachments | 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 Multiparametric performance comparison of dental composites for clear aligner attachments Yunlin Guan, Jiarong Xu, Junhong Qiu, Hao Cai, Wenxuan Xia, Zhou Ye, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6736420/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 19 Jul, 2025 Read the published version in BMC Oral Health → Version 1 posted 10 You are reading this latest preprint version Abstract Background: As clear aligner technology (CAT) gains prominence, the performance of composite attachments - critical devices for optimizing aligner retention and tooth movement control - require systematic evaluation. This study assesses three light-cured composites (Filtek™ Z250 XT, Z350 XT, and P60; 3M ESPE) regarding color stability, shear bond strength (SBS), and durability to establish evidence-based selection criteria. Methods: Attachments were bonded to mandibular premolars, simulating the clinical process, and materials were tested for color changes (after immersion in coffee, cola, or iced tea), SBS, and durability (wear volume, surface roughness, morphology, post-aging SBS). The data obtained from the study were statistically evaluated via the Shapiro-Wilk test, the Levene test, t-tests, one-way analysis of variance and chi-square test. A p -value < 0.05 was considered statistically significant. Results: Z250 showed significantly higher coffee - induced discoloration than Z350 ( p < 0.05) and P60 ( p < 0.01), exceeding clinical acceptability (ΔE 00 ≥ 3.3). Z250 also emerged similar trends with cola and iced tea. Z350 exhibited the highest immediate SBS ( p < 0.05 vs. Z250) that may cause enamel damage. P60 demonstrated superior wear resistance, with significantly lower surface roughness (Sq / Sa) than Z250 ( p < 0.001) and Z350 ( p < 0.01), and the smallest post-wear defect volume ( p < 0.01 vs. Z250). The SBS differences in immediate groups were eliminated through aging treatment . Conclusions: Z250 underperformed in color stability, SBS, and durability versus Z350/P60, though demonstrated cost-effectiveness. Z350 offers outstanding color durability and higher SBS but risks enamel damage from interfacial delamination. P60 excels with color stability, acceptable adhesive remnants, and exceptional wear resistance, serving diverse clinical needs. Clinical decisions could prioritize P60 for function-aesthetic balance, with targeted Z350/Z250 use in special scenarios. clear aligner composite attachment color stability shear bond strength durability Figures Figure 1 Figure 2 Figure 3 Figure 4 Background Over the past two decades, advancements in materials and technologies have significantly enhanced Clear Aligner Therapy (CAT). Thanks to the development of 3D imaging and computer-aided design/manufacturing (CAD/CAM) technology, notably, clear orthodontic appliances, such as Clear Aligners, first appeared in 1997. These appliances are uniquely designed, customized to fit each patient’s dental arch, and feature a high aesthetic appeal compared to traditional fixed orthodontic appliances[ 1 ]. Clear Aligners (CA) also possess advantages, including excellent hygiene and comfort, which are essential for patient satisfaction and long-term use[ 2 ]. And with the introduction of innovative materials, such as reversible memory materials and antibacterial coating technology, the efficiency and overall healthiness of CA has been further enhanced[ 3 – 5 ]. As a result, clear orthodontic appliances are increasingly gaining acceptance and preference among patients[ 6 ]. CA achieves precise tooth movement through resin attachments, which are specially designed, created by filling templates with light-cured composite resin materials, then securely bonded to the enamel surface using an adhesive system to form stable connections. The buckle structure is formed between the clear aligners and teeth, which improves the fixation of orthodontic appliance, increases the predictability and effectiveness of tooth movement[ 7 ]. Therefore, the application of resin attachments in CA is of paramount importance. However, the market currently lacks a product design specifically tailored for CA attachments. Common materials such as resin and glass ionomer materials are primarily designed for dental hard tissue repair, their properties do not fully align with the unique requirements of attachment materials[ 8 , 9 ]. The primary application requirements for clear aligner attachment materials include the following aspects: (a) Aesthetic Performance: Resin attachments, as protruding structures on the enamel surface, necessitates improved resistance to prevent discoloration over time. (b) Bonding Performance: Resin attachments must demonstrate reliable adhesion properties during orthodontic treatment to minimize detachment, thereby avoiding compromised treatment efficacy and increased clinical visits. Additionally, minimizing residual adhesive remnants during debonding is essential to prevent enamel damage[ 10 ]. (c) Durability: The effectiveness of clear aligner treatment depends on the structural integrity of the attachments, which are responsible for transmitting orthodontic forces and controlling tooth movement[ 11 ]. Correlatively, there is also a lack of standardized clinical guidelines for selecting materials. Orthodontists often rely on empirical clinical experience rather than objective data. Some recent studies in this field focus narrowly on isolated material properties rather than providing multiparametric evaluations[ 12 – 14 ], the evidentiary basis guiding orthodontists’ selection of attachment materials, consequently, demonstrates methodological constraints. Therefore, a multiplexed evaluation, accurately simulate clinically relevant conditions, is essential to identify suitable attachment materials. Addressing this require, our work conducts a multiparametric performance comparison of Filtek™ Z250 XT, Z350 XT, P60 (3M ESPE, St. Paul, MN, USA), three market-prevalent light-cured composite resin that widely used in clinical practice (Table 1 ). Selected for their biocompatibility, aesthetic versatility, ease of handling, and cost-effectiveness[ 15 , 16 ], these materials were tested according to ISO 4049:2019, under clinically relevant conditions in vitro , to compare their color stability, shear bond strength (SBS), and durability to provide guidance for the selection of optimal attachment materials for CAT. The null hypothesis posits no significant differences among the three materials in these evaluated parameters. Table 1 Information of materials applied in this study. Material Manufacturer Organic matrix Fillers Z250 a 3M ESPE Bis-GMA, Bis-EMA, UDMA, TEGDMA b 0.01–3.5 µm zirconia/Silica (82 wt%) Z350 a 3M ESPE Bis-GMA, Bis-EMA, UDMA, TEGDMA b 5–20 nm silica nanofillers and 0.6–1.4 µm zirconia/Silica nanoclusters (78.5 wt%) P60 a 3M ESPE Bis-GMA, UDMA, Bis-EMA b 0.01–3.5 µm zirconia/Silica (83 wt%) a Z250 = Filtek™ Z250 XT; Z350 = Filtek™ Z350 XT; P60 = Filtek™ P60; b Bisphenol-A-glycidylmethacrylate, Bis-GMA; Bisphenol-A polyethylenglycol dietherdimethacrylate, Bis-EMA; Urethane dimethacrylate, UDMA; Trietyhlenglycol dimetacrylate, TEGDMA. Methods Sample Preparation Mandibular premolars extracted for orthodontic purposes were collected from Affiliated Stomatological Hospital of Nanchang University. The inclusion criteria were caries-free premolars with intact enamel surfaces, while the exclusion criteria included teeth from patients with craniofacial developmental abnormalities, congenital enamel defects, hypomineralization, existing restorations, caries, cracks, or infections[ 13 ]. The collected teeth were cleaned of debris, calculus, and soft tissues using dental scalers, followed by polishing with prophylaxis paste. Disinfection was performed by immersing the teeth in a solution of compound benzalkonium bromide disinfectant (LIRCON, pH = 5.5, benzalkonium bromide 27–33 g/L, China) diluted in distilled water at a 1 : 29 ratio for 72 hours. After disinfection, the teeth were stored in purified water at 37 ℃ until use[ 17 ]. The premolars were embedded in gypsum to simulate dental arch morphology. The models were scanned using an iTero intraoral scanner (Align Technologies, San Jose, CA, USA), and 3Shape Ortho Analyzer software (3Shape A/S, Copenhagen, Denmark) was employed to design vertical rectangular attachments (4 × 2.5 × 2 mm) at the mid-coronal third of the buccal surfaces. STL digital models were exported and 3D-printed to create plastic dental models. Attachment templates were fabricated using a vacuum-forming machine (JG-206 Vacuum Former, Wuhan, China) with 0.6 mm thermoplastic films. The enamel surfaces were cleaned with alcohol swabs and dried with compressed air. The middle third of the buccal surfaces was etched with 35% phosphoric acid for 30 seconds, rinsed with water for 15 seconds, and air-dried. Adper™ Single Bond 2 adhesive (3M ESPE, St. Paul, MN, USA) was applied and light-cured for 3 seconds using a dental curing unit (Woodpecker b-cure, Guangxi, China). The attachment templates were categorized into three groups based on the materials used for filling the templates: Group A: Filled with Filtek™ Z250 XT light-cured composite resin; Group B: Filled with Filtek™ Z350 XT light-cured composite resin; Group C: Filled with Filtek™ P60 light-cured composite resin. Individual templates were trimmed to fit single crowns. After resin filling, the templates were fully adapted to the tooth surfaces and light-cured (400 mW/cm² mode) for 40 seconds. After bonding, the models were stored in distilled water for 24 hours to complete polymerization. These models were used for color stability and SBS testing. For the wear test of durability, silicone molds (7 × 4 × 1 mm) were filled with the three resin materials, flattened using transparent films, and light-cured for 40 seconds. The cured resin blocks were adhesively bonded to plastic caps (diameter: 18 mm) for subsequent mechanical testing. Color Stability Evaluation The resin attachment models of extracted teeth were separated from the dental arch and sequentially immersed in different colored solutions: (1) Coffee solution: Prepared by mixing 5 g of granulated coffee (Nestlé, Switzerland) with 50 mL of 100 ℃ ultrapure water, (2) Cola solution (Coca-Cola Company, USA), (3) Iced tea solution (Wuhan Uni-President Foods Co., Ltd., China). The samples along with 10 mL of each colored solution were placed in 20 mL glass vials and immersed in a water bath at 37 ℃. Each colored solution was used for an immersion period of 8 days, during which the samples were rinsed, and the solution was replaced daily. Photographs of the resin attachment models of the extracted teeth were taken before immersion and after each solution immersion period (8 days, 16 days, 24 days) using a camera with fixed parameters: 5500K color temperature, ISO 250, 20 cm distance and F36 white balance. All photographs were taken under standardized lighting with a blue background and in the same photography studio. The captured images were imported into Colormeter software (Konica Minolta, Inc., Tokyo, Japan). The surface of the attachments was divided into three equal regions: upper, middle, and lower. The intersection points of the diagonals in each region were selected to measure the L, a, and b values, and the average values were calculated. These values were input into the CIEDE2000 formula to calculate the color difference ΔE 00 , where ΔE 00 ≥ 3.3 was considered clinically unacceptable color difference[ 18 ]. The CIEDE2000 formula is as follows: $$\:\varDelta\:{E}_{00}\:=\:\sqrt{\:{\left(\frac{\varDelta\:{L}^{{\prime\:}}}{{S}_{L}}\right)}^{2}+\:{\left(\frac{\varDelta\:{C}^{{\prime\:}}}{{S}_{C}}\right)}^{2}+\:{\left(\frac{\varDelta\:{h}^{{\prime\:}}}{{S}_{h}}\right)}^{2}+\:R·\left(\frac{\varDelta\:{C}^{{\prime\:}}}{{S}_{C}}\right)·\left(\frac{\varDelta\:{h}^{{\prime\:}}}{{S}_{h}}\right)}$$ Shear Bond Strength Measurement Each resin attachment model was embedded in self-curing plastic, and the SBS was measured using an Instron universal testing machine (INSTRON 2343P8241, Norwood, Massachusetts, USA). The unloading force direction was parallel to the long axis of the attachment, and a blade-type loading structure was placed vertically between the rectangular resin attachment and the enamel surface. The loading speed was set at 1mm/min, and the computer recorded the force value in Newtons (N) at the moment of attachment detachment (Fig. 2 A) [ 19 ]. According to the attachment size data in the experimental design, the base area of the attachment was 10 mm², and the bond strength was calculated using the following formula: Bond Strength (MPa) = Maximum Load (N)/Attachment Base Area (mm²). After the SBS test, the enamel surface condition after attachment detachment and the resin bonding residual area on the enamel surface were observed under a stereomicroscope (Leica EZ4W, Wetzlar, Germany) at 10 × magnification, and the adhesive remnant index (ARI) was recorded (Fig. 2 B) [ 20 ]. Durability experiment Wear test 3 mL of artificial saliva were poured into a plastic cap fixed with a resin block, submerging the resin block, and placed on the stage of a simulated wear device. Under a 2.5 kg load, a metal stainless steel grinding head (diameter = 2 mm) was applied to the specimen, and horizontal relative motion wear was performed along a 3 mm linear path at a frequency of 1 Hz for a total of 1000 reciprocating cycles (Fig. 3 A). After the wear operation, the resin block was removed, rinsed for 1 minute, and the surface water was blown dry. The surface of each specimen was recorded using an optical profiler (Bruker Corporation, Billerica, MA, USA). The surface roughness values Sa and Sq were directly obtained by detecting the surface of each specimen before and after wear using the optical profiler. The volume of the worn area was calculated based on the average pit depth after wear and the area of the shooting window, using the height level line of the unworn area as a reference. The surface morphology after wear was photographed under a stereomicroscope at 10 × magnification. The surface roughness and micro-morphology of the resin attachment after wear were observed using a scanning electron microscope (SEM) (Fig. 3 B). Aging test The resin attachment models were placed in a perforated metal container and aged in a thermo Neslab EX-7 recirculating bath (Marshall Scientific, Hampton, NH, USA) for 3 months, which involved 10,000 thermal cycles between 5 ℃ and 55 ℃ with a dwell time of 30 seconds and a transfer time of 5 seconds (Fig. 4 A) [ 21 ]. After the aging treatment, the models were subsequently subjected to both the SBS experiment and ARI evaluation, following the standardized methodology described in previous sections. Statistical analysis Using SPSS 25.0 software (IBM Corporation, Armonk, New York, USA), data were presented as “mean ± standard deviation”. Normality was assessed using the Shapiro-Wilk test, and homogeneity of variances was evaluated using Levene’s test. For comparisons between non-aged and aged groups of the same material, independent samples t-tests were conducted. One-way analysis of variance (ANOVA) was used for comparisons among different materials. A p -value < 0.05 was considered statistically significant. For non-normally distributed data ( p < 0.05), Kruskal-Wallis H test was used for between-group comparisons. Categorical data were analyzed using the chi-square test for independence (row × column chi-square test). Results Color stability evaluation After 8 days of coffee immersion, the ΔE 00 value of Z250 (7.787 ± 2.10) was significantly higher than that of Z350 ( p < 0.05) and P60 ( p < 0.001). The color changes of both Z250 and Z350 exceeded the clinically acceptable range (ΔE 00 ≥ 3.3). After 8 days of immersion in cola (ΔE 00 = 3.65 ± 1.25) and iced tea (ΔE 00 = 3.795 ± 1.55), the color changes of Z250 also exceeded the clinically acceptable range, but there were no statistical significant differences among the groups (Table 2 , Fig. 1 ). Table 2 The ΔE 00 of tested materials after immersion in coffee, cola, and iced tea. Materials Coffee Cola Iced tea Z250 7.78 ± 2.10 b,B 3.65 ± 1.25 a,A 3.78 ± 1.55 a,A Z350 4.57 ± 1.79 a,B 1.79 ± 0.74 a,A 3.28 ± 1.58 a,AB P60 2.54 ± 1.08 a,A 2.39 ± 1.48 a,A 3.20 ± 0.94 a,A A, B Indicate statistically significant differences in the row. a, b Indicate statistically significant differences in the column. Significant difference ( p < .05). Shear Bond Strength Measurement The immediate measurement results showed that the SBS of Z350 was significantly higher than that of Z250 ( p < 0.01). The SBS of P60 was also higher than that of Z250, but there was no significant difference between the groups (Fig. 2 C). After the shear test, Z350 showed the most adhesive residue, but there were no statistically significant differences in the ARI results of the three materials in the immediate groups (Fig. 2 D). Durability experiment Wear test The data from the optical profiler showed that the Sq and Sa values of P60 after wear were the smallest, with significant differences compared to Z250 and Z350, while the Sq and Sa values of Z250 were the largest (Fig. 3 C). The SEM results showed that the surface of P60 after wear was the smoothest, while the surface of Z250 was the roughest, indicating that the actual observations were consistent with the measured values (Fig. 3 B). There was a statistically significant difference in the wear defect volume between Z250 and P60 ( p < 0.01). Specifically, the wear defect volume of P60 was smaller than that of Z250. The wear defect volume of Z350 fell between the other two materials in terms of mean value (Fig. 3 D). Aging test After the aging cycle, the order of SBS from high to low was consistent with the immediate measurement results, that is, Z350 had the highest SBS and Z250 had the lowest, but there were no significant differences among the groups. The SBS of each material after aging was higher than the immediate measurement results (Fig. 4 B). P60 had the least adhesive residue in the after-aging group than others. Both Z350/P60’s adhesive residue decreased after aging, while that of Z250 was basically consistent with the non-aging group (Fig. 4 C). Discussion This study evaluated the color stability, SBS, and durability of three dental resin composites (Z250, Z350, P60) under simulated clinical conditions. Color stability testing involved immersing materials in coffee, cola, and iced tea especially at physiological temperatures. The results of this evaluation revealed that Z250 exhibited a color difference exceeding the clinically acceptable range after soaking in all three colored solutions, with the largest color difference observed after 8 days of soaking in coffee. The phenomenon may be attributed to Z250’s micron-scale silica fillers (0.01–3.5 µm) and highest resin matrix content, which exhibits higher surface roughness and water absorption rate, enhancing adsorption capacity for water-soluble chromogens (e.g., coffee and tea)[ 22 ]. In contrast, Z350 incorporates densely packed nanoscale fillers that create a smoother surface and minimize resin matrix exposure. The superior color stability of Z350 observed in this study can be attributed to its structural advantage, which reduces pigment adsorption. P60 combines high-density fillers with reduction of resin matrix[ 23 ], that may minimize light scattering and shorten the propagation path within the composite. This reduction in scattering intensity might result in a less perceptible overall color change, enhancing the material’s aesthetic stability[ 24 ]. Meanwhile, the composition of staining solutions has chance to influence outcomes. The acidity of cola may potentially weaken the filler-matrix interface in P60 composites due to hydrolysis of silane coupling agents, which could contribute to increased chromatic divergence compared to Z350. Conversely, the tannic acid and polyphenols in coffee or iced tea appear to interact preferentially with Z350 surfaces, potentially through hydrogen bonding with Si-OH groups, which may lead to comparatively more noticeable color discrepancies than those seen with P60 surfaces[ 25 ]. Therefore, for high esthetic requirement patients, Z250 should be used with caution due to its susceptibility to unacceptable color changes after exposure to common beverages. Z350 and P60 offer better color stability thanks to their filler structures. Clinicians should match dental resin materials with patients’ beverage consumption habits. For patients who frequently drink cola, it is advisable to choose alternatives to Z350 due to potential degradation risks in P60 and encourage them to reduce cola intake. Similarly, for those who regularly consume iced tea, refrain from using Z350, and suggest limiting intake of these beverages. The immediate SBS results of all the three materials exceeded the clinically required range (6–8 MPa)[ 26 ], while Z250 showing the lowest strength, that may due to its lower filler ratio resulting in insufficient material rigidity and propensity to develop stress concentration points, predisposing cohesive failure. Simultaneously, the elevated matrix content within Z250 predisposes the material to intensified polymerization shrinkage stress, which mechanistically induces micrometer-scale interfacial cracks at the resin-enamel junction through anisotropic contraction patterns, thereby compromising SBS to some extent. Z350’s nanofiller arrangement displays enhanced rigidity than Z250, that achieve optimal SBS with compatible bonding agents[ 27 ]. P60’s hybrid fillers and highly crosslinked matrix tend to exhibit relatively superior inherent rigidity and comparatively minimal polymerization shrinkage, which may contribute to satisfactory mechanical hardness performance. The ARI analysis revealed a predominant incidence of ARI score 0 in Z250 group, indicating a feasible monolithic debonding through bulk removal using a needle holder. It appears to reduce chairside time and minimize enamel damage. Conversely, Z350/P60 groups showed higher ARI scores suggesting difficulty in attachment removal, where controlled grinding protocols using high-speed turbines avoid catastrophic interfacial delamination-induced enamel fractures observed in direct peel-off methods. In the durability testing, P60 exhibited the lowest roughness and wear volume, outperforming Z250 and Z350. These differences may be attributed to variations in filler characteristics, including size, shape, content, orientation, and distribution within the composite resin[ 28 ]. The observed superior wear resistance of P60 during wear cycles may be associated with its higher filler loading and potentially optimized filler-matrix coupling, demonstrating enhanced mechanical strength[ 29 ]. P60’s filler size and orientation, enabling uniform stress distribution and a “self-polishing” mechanism, forming enamel-like smooth surfaces. Its lower resin matrix content simultaneously appears to prevent localized excessive matrix abrasion. Conversely, Z250/Z350’s higher resin matrix content more likely lead to preferential matrix wear, exposing fillers and increasing roughness. Specifically, Z250’s micrometer-filler seems to create relatively heightened surface roughness post-wear compared to nanoscale-filled Z350. In clinical condition, P60’s relatively smooth surface after wear may reduce bacterial biofilm formation on the material surface to a certain extent[ 30 ], which is beneficial for maintaining oral hygiene and enamel health. Additionally, its small wear defect volume might indicate minimal wear deformation during aligner insertion and removal, which is advantageous for long-term force application and stability in CAT. After the aging test, particularly treated with thermal cycling, all three materials demonstrated increased SBS, that may attribute to the post-curing effect of light-activated resins. It was likely Z250 had a lower initial resin matrix crosslinking degree, which increased significantly during aging, densifying its structure and boosting SBS. In comparison, Z350 and P60 had higher initial crosslinking, with less aging-induced change. Thus, Z250’s substantial SBS improvement bridged the gap, eliminating group differences. Hydroplasticization mediated by water-sorption phenomena facilitates a brittle-to-ductile transition in resin matrices through plasticizer-like molecular interactions, appears to enhance fracture resistance. Simultaneously, Ca²⁺ and PO₄³⁻ ions in artificial saliva may deposit hydroxyapatite-like microlayers in ideal condition, filling micro cracks and reinforcing resin-enamel interfaces[ 31 ]. These findings suggest that restorations exhibit reduced risk of debonding during clinical aging. Overall, P60 demonstrated an outstanding overall performance, while clinical observations indicate that it demonstrates limited adoption in routine practice. Z250 and Z350 remain predominant choices among prosthodontists and orthodontists based on empirical surveys. This may be because resins have traditionally been used for restoration, which emphasizes precise color matching. Therefore, Z350 and Z250 are more popular due to their broader shade selection. However, the application scenarios of orthodontic attachment differ from those of restorative resins. Aligner attachments are mostly used on posterior teeth, and even when used on anterior teeth, they are only applied temporarily or in small areas, resulting in less stringent requirements for shade aesthetics compared to restorative procedures. As such, P60’s overall performance is more suitable for orthodontic attachments. This study not only provides evidence-based support for challenging conventional material application norms but also provides clinical guidance for selecting attachment materials. It is suggested that clinicians prioritize P60 when seeking an optimal balance between functionality and aesthetics, employ Z350 to meet higher aesthetic requirements with more color options, and consider Z250 as an economical alternative. Nevertheless, our work retains limitations characteristic of in vitro methodologies, including incomplete simulation of critical oral environmental factors such as dynamic pH fluctuations, bacterial biofilm interactions, and salivary enzyme activity[ 32 ]. To establish robust clinical correlations, future investigations should incorporate in vivo analyses coupled with controlled clinical trials, thereby validating material performance under physiologically relevant multi-factor oral environments. Conclusions This study conclusively rejected the null hypothesis, demonstrating statistically significant variations in color stability, SBS, and durability across the tested materials. Z250 underperformed than Z350 and P60 in terms of color stability, shear bond strength, and durability tests. Z350 exhibits superior aesthetic properties and achieves effective bonding through higher SBS, however, the predominant presence of adhesive remnant at the failure interface indicates that direct interfacial delamination poses a higher risk of enamel damage, whereas meticulous removal using a high-speed turbine handpiece can mitigate such iatrogenic risks. P60 excels with clinically acceptable color stability, residual adhesive remnants and exceptional wear resistance, suggesting superior suitability for common orthodontic attachments requiring long-term functional durability and aesthetic preservation. Clinical decision-making should be guided by a three-dimensional framework encompassing aesthetic demand intensity, treatment duration, and cost sensitivity, prioritizing P60 to achieve an optimal balance between function and aesthetic. Targeted application of Z350/Z250 is recommended for specific clinical scenarios, complemented by standardized bonding protocols and patient behavior management to optimize treatment outcomes. Declarations Ethics approval and consent to participate This study was approved by the medical ethics committee of the Affiliated Stomatology Hospital of Nanchang University, China, Ethics Approval Number: (Ethical Review of Dentistry 2024 No. (084)). The use of human tissue samples was performed in accordance with relevant guidelines and regulations. All methods were carried out in accordance with the principles of the Declaration of Helsinki. Written informed consent was obtained from all participants prior to inclusion in this study. The consent process included detailed explanations of research objectives, procedures, risks, and benefits, and participants retained the right to withdraw at any stage. Clinical trial number Not applicable. Consent for publication Not applicable. Competing interests The authors declare no competing interests. Authors’ information 1 School of Stomatology, Jiangxi Medical College, Nanchang University, Nanchang, 330000, Jiangxi, China. 2 Jiangxi Provincial Key Laboratory of Oral Diseases and Jiangxi Provincial Clinical Research Center for Oral Diseases, Nanchang, 330000, Jiangxi, China. 3 Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong S.A.R., China. 4 Department of Stomatology, Liuzhou Worker’s Hospital, Liuzhou, 545000, Guangxi Zhuang Autonomous Region, China. Funding This work was supported by the National Natural Science Foundation of China [grant number 82460186]. Author Contribution Yunlin Guan: Methodology, Writing-Original Draft, Software, Formal analysis, Investigation, Visualization, Validation. Jiarong Xu: Methodology, Validation, Investigation, Formal analysis. Junhong Qiu: Methodology, Software, Visualization. Hao Cai: Methodology, Data Curation.Wenxuan Xia: Methodology, Visualization. Zhou Ye: Data Curation, Supervision, Resources, Writing-Editing.Ting Sang: Conceptualization, Methodology, Visualization, Resources, Supervision, Data Curation, Writing-Editing. Acknowledgements Not applicable. Data Availability The data supporting the findings of this study are available from the corresponding author upon reasonable request. References Narongdej P, Hassanpour M, Alterman N, Rawlins-Buchanan F, Barjasteh E. Advancements in clear aligner fabrication: A comprehensive review of direct-3D printing technologies. Polymers. 2024;16:371. AlMogbel A. Clear Aligner Therapy: Up to date review article. J Orthod Sci. 2023;12:37. Tamburrino F, D’Antò V, Bucci R, Alessandri-Bonetti G, Barone S, Razionale AV. Mechanical properties of thermoplastic polymers for aligner manufacturing: In vitro study. Dentistry J. 2020;8:47. Bichu YM, Alwafi A, Liu X, Andrews J, Ludwig B, Bichu AY, et al. Advances in orthodontic clear aligner materials. Bioactive Mater. 2023;22:384–403. Cenzato N, Di Iasio G, Martìn Carreras-Presas C, Caprioglio A, Del Fabbro M. Materials for clear aligners—a comprehensive exploration of characteristics and innovations: A scoping review. Appl Sci. 2024;14:6533. Yu X, Li G, Zheng Y, Gao J, Fu Y, Wang Q, et al. Invisible’ orthodontics by polymeric ‘clear’ aligners molded on 3D-printed personalized dental models. Regenerative Biomaterials. 2022;9:rbac007. Ahmad W, Jiang F, Xiong J, Xia Z. The mechanical effect of geometric design of attachments in invisible orthodontics. Am J Orthod Dentofac Orthop. 2023;164:183–93. Akhtar K, Pervez C, Zubair N, Khalid H. Calcium hydroxyapatite nanoparticles as a reinforcement filler in dental resin nanocomposite. J Mater Sci - Mater Med. 2021;32:129. Saini RS, Binduhayyim RIH, Gurumurthy V, Alshadidi AAF, Aldosari LIN, Okshah A, et al. Dental biomaterials redefined: Molecular docking and dynamics-driven dental resin composite optimization. BMC Oral Health. 2024;24:1–18. Donmez MB, Çakmak G, Yılmaz D, Schimmel M, Abou-Ayash S, Yilmaz B et al. Bond strength of additively manufactured composite resins to dentin and titanium when bonded with dual-polymerizing resin cements. J Prosthet Dent. 2023;:S0022-3913(23)00255-X. A F da VJ JC, de F CE. Surface wear and adhesive failure of resin attachments used in clear aligner orthodontic treatment. J Orofac Orthop. 2024;85 Suppl 1. Cao L, Zhao X, Gong X, Zhao S. An in vitro investigation of wear resistance and hardness of composite resins. Int J Clin Exp Med. 2013;6:423–30. Erçin Ö, Kurnaz M, Kopuz D. Evaluation of the color stability of attachments made with different resin composites. Am J Orthod Dentofac Orthop. 2023;164:e121–8. Kircelli BH, Kilinc DD, Karaman A, Sadry S, Gonul EY, Gögen H. Comparison of the bond strength of five different composites used in the production of clear aligner attachments. J Stomatology Oral Maxillofacial Surg. 2023;124:101481. Pazinatto FB, Gionordoli Neto R, Wang L, Mondelli J, Mondelli RFL. Navarro MF de L. 56-month clinical performance of class I and II resin composite restorations. J Appl Oral Sci. 2012;20:323–8. Catalán A, Martínez A, Muñoz C, Medina C, Marzialetti T, Montaño M, et al. The effect of preheating of nano-filler composite resins on their degree of conversion and microfiltration in dental fillings. Polym Bull. 2022;79:10707–22. Chen W, Qian L, Qian Y, Zhang Z, Wen X. Comparative study of three composite materials in bonding attachments for clear aligners. Orthod Craniofac Res. 2021;24:520–7. Luo MR, Cui G, Rigg B. The development of the CIE 2000 colour-difference formula: CIEDE2000. Color Res Appl. 2001;26:340–50. Yassaei S, Davari A, Goldani Moghadam M, Kamaei A. Comparison of Shear Bond Strength of RMGI and Composite Resin for Orthodontic Bracket Bonding. J Dent (Tehran). 2014;11:282–9. Peng S, Sang T, Wang H, Guan Y, Deng Y, Wang P, et al. Bioinspired anti-demineralization enamel coating for orthodontics. J Dent Res. 2022;101:1620–7. Moussa DG, Fok A, Aparicio C. Hydrophobic and antimicrobial dentin: A peptide-based 2-tier protective system for dental resin composite restorations. Acta Biomater. 2019;88:251–65. Abdallah M-N, Light N, Amin WM, Retrouvey J-M, Cerruti M, Tamimi F. Development of a composite resin disclosing agent based on the understanding of tooth staining mechanisms. J Dent. 2014;42:697–708. Li Q, Zhan N, Ng T, Swain MV, Wan B, Jian Y, et al. The influence of hygroscopic expansion of resin supporting dies on the fracture resistance of ceramic restorations during thermal cycling. Dent Mater. 2024;40:1231–43. Oivanen M, Keulemans F, Garoushi S, Vallittu PK, Lassila L. The effect of refractive index of fillers and polymer matrix on translucency and color matching of dental resin composite. Biomater Investig Dent 8:48–53. Gonulol N, Ozer S, Sen Tunc E. Water sorption, solubility, and color stability of giomer restoratives. J Esthet Restor Dent. 2015;27:300–6. Kircelli BH, Kilinc DD, Karaman A, Sadry S, Gonul EY, Gögen H. Comparison of the bond strength of five different composites used in the production of clear aligner attachments. J Stomatology Oral Maxillofacial Surg. 2023;124:101481. Rodríguez HA, Kriven WM, Casanova H. Development of mechanical properties in dental resin composite: Effect of filler size and filler aggregation state. Mater Sci Engineering: C. 2019;101:274–82. Biçer Z, Yaman BC, Çeliksöz Ö, Tepe H. Surface roughness of different types of resin composites after artificial aging procedures: An in vitro study. BMC Oral Health. 2024;24:876. Kakuta K, Wonglamsam A, Goto S-I, Ogura H. Surface textures of composite resins after combined wear test simulating both occlusal wear and brushing wear. Dent Mater J. 2012;31:61–7. Choi S, Jo Y-H, Luke Yeo I-S, Yoon H-I, Lee J-H, Han J-S. The effect of surface material, roughness and wettability on the adhesion and proliferation of streptococcus gordonii , fusobacterium nucleatum and porphyromonas gingivalis . J Dent Sci. 2023;18:517–25. Ju K, Zhao Z, Chen X, Liu X, Li J. Preparation and growth behaviours of low porosity hydroxyapatite with enhanced adhesion by electrochemical deposition on micro-arc oxide coatings. Surf Coat Technol. 2023;473:130017. Alhotan A, Raszewski Z, Alamoush RA, Chojnacka K, Mikulewicz M, Haider J. Influence of Storing Composite Filling Materials in a Low-pH Artificial Saliva on Their Mechanical Properties—An In Vitro Study. J Funct Biomaterials. 2023;14:328. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 19 Jul, 2025 Read the published version in BMC Oral Health → Version 1 posted Editorial decision: Revision requested 19 Jun, 2025 Reviews received at journal 18 Jun, 2025 Reviews received at journal 17 Jun, 2025 Reviewers agreed at journal 12 Jun, 2025 Reviewers agreed at journal 12 Jun, 2025 Reviewers invited by journal 11 Jun, 2025 Editor assigned by journal 11 Jun, 2025 Editor invited by journal 03 Jun, 2025 Submission checks completed at journal 03 Jun, 2025 First submitted to journal 03 Jun, 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-6736420","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":470567349,"identity":"28167656-6cb3-4bcd-bade-04e4b3788512","order_by":0,"name":"Yunlin Guan","email":"","orcid":"","institution":"Nanchang University","correspondingAuthor":false,"prefix":"","firstName":"Yunlin","middleName":"","lastName":"Guan","suffix":""},{"id":470567350,"identity":"c5cc4f87-a8fd-47d9-b685-669a42404f09","order_by":1,"name":"Jiarong Xu","email":"","orcid":"","institution":"University of Hong Kong","correspondingAuthor":false,"prefix":"","firstName":"Jiarong","middleName":"","lastName":"Xu","suffix":""},{"id":470567351,"identity":"cc39aee5-0f22-47c0-8f36-89b2f2230a0f","order_by":2,"name":"Junhong Qiu","email":"","orcid":"","institution":"Nanchang University","correspondingAuthor":false,"prefix":"","firstName":"Junhong","middleName":"","lastName":"Qiu","suffix":""},{"id":470567352,"identity":"347bea30-f83d-42e9-95df-0dc671a376ab","order_by":3,"name":"Hao Cai","email":"","orcid":"","institution":"Liuzhou worker's hospital","correspondingAuthor":false,"prefix":"","firstName":"Hao","middleName":"","lastName":"Cai","suffix":""},{"id":470567353,"identity":"c7ffa5e0-143f-4c5a-8485-6113a67efa59","order_by":4,"name":"Wenxuan Xia","email":"","orcid":"","institution":"Nanchang University","correspondingAuthor":false,"prefix":"","firstName":"Wenxuan","middleName":"","lastName":"Xia","suffix":""},{"id":470567354,"identity":"6b45ae5e-ecf5-44c6-beaa-a40622e36625","order_by":5,"name":"Zhou Ye","email":"","orcid":"","institution":"University of Hong Kong","correspondingAuthor":false,"prefix":"","firstName":"Zhou","middleName":"","lastName":"Ye","suffix":""},{"id":470567355,"identity":"27e40bff-a453-4ed0-9412-c4432cde509a","order_by":6,"name":"Ting Sang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAxUlEQVRIiWNgGAWjYNACAwYGefYGUnQcAGox7DlAkhYQcSOBSNXy7WcPv/5QcMeucebjjTcYamyiCWoxOJOXZnHA4Flyu3RasQXDsbTcBoJaGHLMDA4YHE5mnJ1jJsHYcJiwFvn+NxAtDDfPEKmF4UaO8QOgFjuGGzxEajG48caM4YzB4QTDHqBfEojxi3x/jvGHij+H7eXZD2+88aHGhgiHMTCwSQCJRKBKA4kEIpSDAPMHIGEPcqQEkTpGwSgYBaNghAEAtn9DbBt2pGsAAAAASUVORK5CYII=","orcid":"","institution":"Nanchang University","correspondingAuthor":true,"prefix":"","firstName":"Ting","middleName":"","lastName":"Sang","suffix":""}],"badges":[],"createdAt":"2025-05-24 03:23:18","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6736420/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6736420/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12903-025-06623-w","type":"published","date":"2025-07-19T16:05:35+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":84703467,"identity":"9190d9ba-405c-4e4d-a56c-b4f86112e631","added_by":"auto","created_at":"2025-06-16 11:54:22","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":16481461,"visible":true,"origin":"","legend":"\u003cp\u003eColor stability testing methodology and experimental outcomes.\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-6736420/v1/bfca9343d83e59a691906d40.png"},{"id":84703938,"identity":"ea5ec26f-e027-4919-ad0f-dec2e24b4173","added_by":"auto","created_at":"2025-06-16 12:02:23","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":22918547,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eA.\u003c/strong\u003e The model for SBS test. \u003cstrong\u003eB.\u003c/strong\u003eRepresentative images of classification of ARI: 0 represents the absence of residual resin on the enamel surface; 1 represents less than half of the residual resin remains; 2 represents more than half of the residual resin remains; 3 represents almost all residual resin remains. \u003cstrong\u003eC.\u003c/strong\u003e Immediate SBS of three materials. \u003cstrong\u003eD.\u003c/strong\u003e ARI results after SBS test.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-6736420/v1/d673c9473d896e44ad02411a.png"},{"id":84703937,"identity":"ef08cd58-1ebc-47d4-8ede-7c2f58034802","added_by":"auto","created_at":"2025-06-16 12:02:23","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":25107127,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eA.\u003c/strong\u003e An abrasion model simulating aligner insertion and removal in oral. \u003cstrong\u003eB.\u003c/strong\u003e SEM pictures of materials’ surface after abrasion. \u003cstrong\u003eC.\u003c/strong\u003e Post-wear surface roughness (Sq and Sa values). \u003cstrong\u003eD.\u003c/strong\u003eWear-induced defect volume.\u003c/p\u003e","description":"","filename":"Figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-6736420/v1/1579cd72adbdb2772d3e945e.png"},{"id":84703459,"identity":"64c0335d-f4a9-4809-80e8-51a7c311ed83","added_by":"auto","created_at":"2025-06-16 11:54:22","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":7113616,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eA. \u003c/strong\u003eAging treatment conducted by thermal cycling. \u003cstrong\u003eB. \u003c/strong\u003eSBS after aging.\u003cstrong\u003e C. \u003c/strong\u003eResults of ARI.\u003c/p\u003e","description":"","filename":"Figure4.png","url":"https://assets-eu.researchsquare.com/files/rs-6736420/v1/92421947e8f251fbd517b9b3.png"},{"id":88506133,"identity":"9bf8b8e2-a2d5-4f2b-9a47-fa45da7faa6f","added_by":"auto","created_at":"2025-08-07 07:31:36","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":68514992,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6736420/v1/cf15b394-47b2-4a93-aa74-ce327c1e89a1.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Multiparametric performance comparison of dental composites for clear aligner attachments","fulltext":[{"header":"Background","content":"\u003cp\u003eOver the past two decades, advancements in materials and technologies have significantly enhanced Clear Aligner Therapy (CAT). Thanks to the development of 3D imaging and computer-aided design/manufacturing (CAD/CAM) technology, notably, clear orthodontic appliances, such as Clear Aligners, first appeared in 1997. These appliances are uniquely designed, customized to fit each patient\u0026rsquo;s dental arch, and feature a high aesthetic appeal compared to traditional fixed orthodontic appliances[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Clear Aligners (CA) also possess advantages, including excellent hygiene and comfort, which are essential for patient satisfaction and long-term use[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. And with the introduction of innovative materials, such as reversible memory materials and antibacterial coating technology, the efficiency and overall healthiness of CA has been further enhanced[\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. As a result, clear orthodontic appliances are increasingly gaining acceptance and preference among patients[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eCA achieves precise tooth movement through resin attachments, which are specially designed, created by filling templates with light-cured composite resin materials, then securely bonded to the enamel surface using an adhesive system to form stable connections. The buckle structure is formed between the clear aligners and teeth, which improves the fixation of orthodontic appliance, increases the predictability and effectiveness of tooth movement[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Therefore, the application of resin attachments in CA is of paramount importance.\u003c/p\u003e \u003cp\u003eHowever, the market currently lacks a product design specifically tailored for CA attachments. Common materials such as resin and glass ionomer materials are primarily designed for dental hard tissue repair, their properties do not fully align with the unique requirements of attachment materials[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. The primary application requirements for clear aligner attachment materials include the following aspects: (a) Aesthetic Performance: Resin attachments, as protruding structures on the enamel surface, necessitates improved resistance to prevent discoloration over time. (b) Bonding Performance: Resin attachments must demonstrate reliable adhesion properties during orthodontic treatment to minimize detachment, thereby avoiding compromised treatment efficacy and increased clinical visits. Additionally, minimizing residual adhesive remnants during debonding is essential to prevent enamel damage[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. (c) Durability: The effectiveness of clear aligner treatment depends on the structural integrity of the attachments, which are responsible for transmitting orthodontic forces and controlling tooth movement[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e Correlatively, there is also a lack of standardized clinical guidelines for selecting materials. Orthodontists often rely on empirical clinical experience rather than objective data. Some recent studies in this field focus narrowly on isolated material properties rather than providing multiparametric evaluations[\u003cspan additionalcitationids=\"CR13\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], the evidentiary basis guiding orthodontists\u0026rsquo; selection of attachment materials, consequently, demonstrates methodological constraints. Therefore, a multiplexed evaluation, accurately simulate clinically relevant conditions, is essential to identify suitable attachment materials.\u003c/p\u003e \u003cp\u003eAddressing this require, our work conducts a multiparametric performance comparison of Filtek\u0026trade; Z250 XT, Z350 XT, P60 (3M ESPE, St. Paul, MN, USA), three market-prevalent light-cured composite resin that widely used in clinical practice (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Selected for their biocompatibility, aesthetic versatility, ease of handling, and cost-effectiveness[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e], these materials were tested according to ISO 4049:2019, under clinically relevant conditions \u003cem\u003ein vitro\u003c/em\u003e, to compare their color stability, shear bond strength (SBS), and durability to provide guidance for the selection of optimal attachment materials for CAT. The null hypothesis posits no significant differences among the three materials in these evaluated parameters.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eInformation of materials applied in this study.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMaterial\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eManufacturer\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eOrganic matrix\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eFillers\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZ250\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3M ESPE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eBis-GMA, Bis-EMA, UDMA, TEGDMA\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.01\u0026ndash;3.5 \u0026micro;m zirconia/Silica\u003c/p\u003e \u003cp\u003e(82 wt%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZ350\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3M ESPE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eBis-GMA, Bis-EMA, UDMA, TEGDMA\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5\u0026ndash;20 nm silica nanofillers and\u003c/p\u003e \u003cp\u003e0.6\u0026ndash;1.4 \u0026micro;m zirconia/Silica nanoclusters (78.5 wt%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eP60\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3M ESPE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eBis-GMA, UDMA,\u003c/p\u003e \u003cp\u003eBis-EMA\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.01\u0026ndash;3.5 \u0026micro;m zirconia/Silica\u003c/p\u003e \u003cp\u003e(83 wt%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003e\u003csup\u003ea\u003c/sup\u003e Z250\u0026thinsp;=\u0026thinsp;Filtek\u0026trade; Z250 XT; Z350\u0026thinsp;=\u0026thinsp;Filtek\u0026trade; Z350 XT; P60\u0026thinsp;=\u0026thinsp;Filtek\u0026trade; P60;\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003e\u003csup\u003eb\u003c/sup\u003e Bisphenol-A-glycidylmethacrylate, Bis-GMA; Bisphenol-A polyethylenglycol dietherdimethacrylate, Bis-EMA; Urethane dimethacrylate, UDMA; Trietyhlenglycol dimetacrylate, TEGDMA.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eSample Preparation\u003c/h2\u003e \u003cp\u003eMandibular premolars extracted for orthodontic purposes were collected from Affiliated Stomatological Hospital of Nanchang University. The inclusion criteria were caries-free premolars with intact enamel surfaces, while the exclusion criteria included teeth from patients with craniofacial developmental abnormalities, congenital enamel defects, hypomineralization, existing restorations, caries, cracks, or infections[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe collected teeth were cleaned of debris, calculus, and soft tissues using dental scalers, followed by polishing with prophylaxis paste. Disinfection was performed by immersing the teeth in a solution of compound benzalkonium bromide disinfectant (LIRCON, pH\u0026thinsp;=\u0026thinsp;5.5, benzalkonium bromide 27\u0026ndash;33 g/L, China) diluted in distilled water at a 1 : 29 ratio for 72 hours. After disinfection, the teeth were stored in purified water at 37 ℃ until use[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe premolars were embedded in gypsum to simulate dental arch morphology. The models were scanned using an iTero intraoral scanner (Align Technologies, San Jose, CA, USA), and 3Shape Ortho Analyzer software (3Shape A/S, Copenhagen, Denmark) was employed to design vertical rectangular attachments (4 \u0026times; 2.5 \u0026times; 2 mm) at the mid-coronal third of the buccal surfaces. STL digital models were exported and 3D-printed to create plastic dental models. Attachment templates were fabricated using a vacuum-forming machine (JG-206 Vacuum Former, Wuhan, China) with 0.6 mm thermoplastic films.\u003c/p\u003e \u003cp\u003eThe enamel surfaces were cleaned with alcohol swabs and dried with compressed air. The middle third of the buccal surfaces was etched with 35% phosphoric acid for 30 seconds, rinsed with water for 15 seconds, and air-dried. Adper\u0026trade; Single Bond 2 adhesive (3M ESPE, St. Paul, MN, USA) was applied and light-cured for 3 seconds using a dental curing unit (Woodpecker b-cure, Guangxi, China).\u003c/p\u003e \u003cp\u003eThe attachment templates were categorized into three groups based on the materials used for filling the templates: Group A: Filled with Filtek\u0026trade; Z250 XT light-cured composite resin; Group B: Filled with Filtek\u0026trade; Z350 XT light-cured composite resin; Group C: Filled with Filtek\u0026trade; P60 light-cured composite resin. Individual templates were trimmed to fit single crowns. After resin filling, the templates were fully adapted to the tooth surfaces and light-cured (400 mW/cm\u0026sup2; mode) for 40 seconds. After bonding, the models were stored in distilled water for 24 hours to complete polymerization. These models were used for color stability and SBS testing.\u003c/p\u003e \u003cp\u003eFor the wear test of durability, silicone molds (7 \u0026times; 4 \u0026times; 1 mm) were filled with the three resin materials, flattened using transparent films, and light-cured for 40 seconds. The cured resin blocks were adhesively bonded to plastic caps (diameter: 18 mm) for subsequent mechanical testing.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eColor Stability Evaluation\u003c/h3\u003e\n\u003cp\u003eThe resin attachment models of extracted teeth were separated from the dental arch and sequentially immersed in different colored solutions: (1) Coffee solution: Prepared by mixing 5 g of granulated coffee (Nestl\u0026eacute;, Switzerland) with 50 mL of 100 ℃ ultrapure water, (2) Cola solution (Coca-Cola Company, USA), (3) Iced tea solution (Wuhan Uni-President Foods Co., Ltd., China). The samples along with 10 mL of each colored solution were placed in 20 mL glass vials and immersed in a water bath at 37 ℃. Each colored solution was used for an immersion period of 8 days, during which the samples were rinsed, and the solution was replaced daily. Photographs of the resin attachment models of the extracted teeth were taken before immersion and after each solution immersion period (8 days, 16 days, 24 days) using a camera with fixed parameters: 5500K color temperature, ISO 250, 20 cm distance and F36 white balance. All photographs were taken under standardized lighting with a blue background and in the same photography studio. The captured images were imported into Colormeter software (Konica Minolta, Inc., Tokyo, Japan). The surface of the attachments was divided into three equal regions: upper, middle, and lower. The intersection points of the diagonals in each region were selected to measure the L, a, and b values, and the average values were calculated. These values were input into the CIEDE2000 formula to calculate the color difference ΔE\u003csub\u003e00\u003c/sub\u003e, where ΔE\u003csub\u003e00\u003c/sub\u003e\u0026thinsp;\u0026ge;\u0026thinsp;3.3 was considered clinically unacceptable color difference[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. The CIEDE2000 formula is as follows:\u003cdiv id=\"Equa\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equa\" name=\"EquationSource\"\u003e\n$$\\:\\varDelta\\:{E}_{00}\\:=\\:\\sqrt{\\:{\\left(\\frac{\\varDelta\\:{L}^{{\\prime\\:}}}{{S}_{L}}\\right)}^{2}+\\:{\\left(\\frac{\\varDelta\\:{C}^{{\\prime\\:}}}{{S}_{C}}\\right)}^{2}+\\:{\\left(\\frac{\\varDelta\\:{h}^{{\\prime\\:}}}{{S}_{h}}\\right)}^{2}+\\:R\u0026middot;\\left(\\frac{\\varDelta\\:{C}^{{\\prime\\:}}}{{S}_{C}}\\right)\u0026middot;\\left(\\frac{\\varDelta\\:{h}^{{\\prime\\:}}}{{S}_{h}}\\right)}$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e\n\u003ch3\u003eShear Bond Strength Measurement\u003c/h3\u003e\n\u003cp\u003eEach resin attachment model was embedded in self-curing plastic, and the SBS was measured using an Instron universal testing machine (INSTRON 2343P8241, Norwood, Massachusetts, USA). The unloading force direction was parallel to the long axis of the attachment, and a blade-type loading structure was placed vertically between the rectangular resin attachment and the enamel surface. The loading speed was set at 1mm/min, and the computer recorded the force value in Newtons (N) at the moment of attachment detachment (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e2\u003c/span\u003eA) [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. According to the attachment size data in the experimental design, the base area of the attachment was 10 mm\u0026sup2;, and the bond strength was calculated using the following formula: Bond Strength (MPa)\u0026thinsp;=\u0026thinsp;Maximum Load (N)/Attachment Base Area (mm\u0026sup2;). After the SBS test, the enamel surface condition after attachment detachment and the resin bonding residual area on the enamel surface were observed under a stereomicroscope (Leica EZ4W, Wetzlar, Germany) at 10 \u0026times; magnification, and the adhesive remnant index (ARI) was recorded (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e2\u003c/span\u003eB) [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\n\u003ch3\u003eDurability experiment\u003c/h3\u003e\n\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eWear test\u003c/h2\u003e \u003cp\u003e3 mL of artificial saliva were poured into a plastic cap fixed with a resin block, submerging the resin block, and placed on the stage of a simulated wear device. Under a 2.5 kg load, a metal stainless steel grinding head (diameter\u0026thinsp;=\u0026thinsp;2 mm) was applied to the specimen, and horizontal relative motion wear was performed along a 3 mm linear path at a frequency of 1 Hz for a total of 1000 reciprocating cycles (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003eA). After the wear operation, the resin block was removed, rinsed for 1 minute, and the surface water was blown dry. The surface of each specimen was recorded using an optical profiler (Bruker Corporation, Billerica, MA, USA). The surface roughness values Sa and Sq were directly obtained by detecting the surface of each specimen before and after wear using the optical profiler. The volume of the worn area was calculated based on the average pit depth after wear and the area of the shooting window, using the height level line of the unworn area as a reference. The surface morphology after wear was photographed under a stereomicroscope at 10 \u0026times; magnification. The surface roughness and micro-morphology of the resin attachment after wear were observed using a scanning electron microscope (SEM) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003eB).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eAging test\u003c/h2\u003e \u003cp\u003eThe resin attachment models were placed in a perforated metal container and aged in a thermo Neslab EX-7 recirculating bath (Marshall Scientific, Hampton, NH, USA) for 3 months, which involved 10,000 thermal cycles between 5 ℃ and 55 ℃ with a dwell time of 30 seconds and a transfer time of 5 seconds (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e4\u003c/span\u003eA) [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. After the aging treatment, the models were subsequently subjected to both the SBS experiment and ARI evaluation, following the standardized methodology described in previous sections.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eUsing SPSS 25.0 software (IBM Corporation, Armonk, New York, USA), data were presented as \u0026ldquo;mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation\u0026rdquo;. Normality was assessed using the Shapiro-Wilk test, and homogeneity of variances was evaluated using Levene\u0026rsquo;s test. For comparisons between non-aged and aged groups of the same material, independent samples t-tests were conducted. One-way analysis of variance (ANOVA) was used for comparisons among different materials. A \u003cem\u003ep\u003c/em\u003e-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant. For non-normally distributed data (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05), Kruskal-Wallis H test was used for between-group comparisons. Categorical data were analyzed using the chi-square test for independence (row \u0026times; column chi-square test).\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eColor stability evaluation\u003c/h2\u003e \u003cp\u003eAfter 8 days of coffee immersion, the ΔE\u003csub\u003e00\u003c/sub\u003e value of Z250 (7.787\u0026thinsp;\u0026plusmn;\u0026thinsp;2.10) was significantly higher than that of Z350 (\u003cem\u003ep\u003c/em\u003e \u0026lt; 0.05) and P60 (\u003cem\u003ep\u003c/em\u003e \u0026lt; 0.001). The color changes of both Z250 and Z350 exceeded the clinically acceptable range (ΔE\u003csub\u003e00\u003c/sub\u003e\u0026thinsp;\u0026ge;\u0026thinsp;3.3). After 8 days of immersion in cola (ΔE\u003csub\u003e00\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;3.65\u0026thinsp;\u0026plusmn;\u0026thinsp;1.25) and iced tea (ΔE\u003csub\u003e00\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;3.795\u0026thinsp;\u0026plusmn;\u0026thinsp;1.55), the color changes of Z250 also exceeded the clinically acceptable range, but there were no statistical significant differences among the groups (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe ΔE\u003csub\u003e00\u003c/sub\u003e of tested materials after immersion in coffee, cola, and iced tea.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMaterials\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCoffee\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCola\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eIced tea\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eZ250\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.78\u0026thinsp;\u0026plusmn;\u0026thinsp;2.10\u003csup\u003eb,B\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.65\u0026thinsp;\u0026plusmn;\u0026thinsp;1.25\u003csup\u003ea,A\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.78\u0026thinsp;\u0026plusmn;\u0026thinsp;1.55\u003csup\u003ea,A\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eZ350\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.57\u0026thinsp;\u0026plusmn;\u0026thinsp;1.79\u003csup\u003ea,B\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.79\u0026thinsp;\u0026plusmn;\u0026thinsp;0.74\u003csup\u003ea,A\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.28\u0026thinsp;\u0026plusmn;\u0026thinsp;1.58\u003csup\u003ea,AB\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eP60\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.54\u0026thinsp;\u0026plusmn;\u0026thinsp;1.08\u003csup\u003ea,A\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.39\u0026thinsp;\u0026plusmn;\u0026thinsp;1.48\u003csup\u003ea,A\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.20\u0026thinsp;\u0026plusmn;\u0026thinsp;0.94\u003csup\u003ea,A\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003e\u003csup\u003eA, B\u003c/sup\u003e Indicate statistically significant differences in the row.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003e\u003csup\u003ea, b\u003c/sup\u003e Indicate statistically significant differences in the column.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eSignificant difference (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.05).\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eShear Bond Strength Measurement\u003c/h2\u003e \u003cp\u003eThe immediate measurement results showed that the SBS of Z350 was significantly higher than that of Z250 (\u003cem\u003ep\u003c/em\u003e \u0026lt; 0.01). The SBS of P60 was also higher than that of Z250, but there was no significant difference between the groups (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e2\u003c/span\u003eC). After the shear test, Z350 showed the most adhesive residue, but there were no statistically significant differences in the ARI results of the three materials in the immediate groups (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e2\u003c/span\u003eD).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eDurability experiment\u003c/h2\u003e \u003cdiv id=\"Sec14\" class=\"Section3\"\u003e \u003ch2\u003eWear test\u003c/h2\u003e \u003cp\u003eThe data from the optical profiler showed that the Sq and Sa values of P60 after wear were the smallest, with significant differences compared to Z250 and Z350, while the Sq and Sa values of Z250 were the largest (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003eC). The SEM results showed that the surface of P60 after wear was the smoothest, while the surface of Z250 was the roughest, indicating that the actual observations were consistent with the measured values (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003eB).\u003c/p\u003e \u003cp\u003eThere was a statistically significant difference in the wear defect volume between Z250 and P60 (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01). Specifically, the wear defect volume of P60 was smaller than that of Z250. The wear defect volume of Z350 fell between the other two materials in terms of mean value (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003eD).\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eAging test\u003c/h2\u003e \u003cp\u003eAfter the aging cycle, the order of SBS from high to low was consistent with the immediate measurement results, that is, Z350 had the highest SBS and Z250 had the lowest, but there were no significant differences among the groups. The SBS of each material after aging was higher than the immediate measurement results (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e4\u003c/span\u003eB). P60 had the least adhesive residue in the after-aging group than others. Both Z350/P60\u0026rsquo;s adhesive residue decreased after aging, while that of Z250 was basically consistent with the non-aging group (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e4\u003c/span\u003eC).\u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study evaluated the color stability, SBS, and durability of three dental resin composites (Z250, Z350, P60) under simulated clinical conditions. Color stability testing involved immersing materials in coffee, cola, and iced tea especially at physiological temperatures. The results of this evaluation revealed that Z250 exhibited a color difference exceeding the clinically acceptable range after soaking in all three colored solutions, with the largest color difference observed after 8 days of soaking in coffee. The phenomenon may be attributed to Z250\u0026rsquo;s micron-scale silica fillers (0.01\u0026ndash;3.5 \u0026micro;m) and highest resin matrix content, which exhibits higher surface roughness and water absorption rate, enhancing adsorption capacity for water-soluble chromogens (e.g., coffee and tea)[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. In contrast, Z350 incorporates densely packed nanoscale fillers that create a smoother surface and minimize resin matrix exposure. The superior color stability of Z350 observed in this study can be attributed to its structural advantage, which reduces pigment adsorption. P60 combines high-density fillers with reduction of resin matrix[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e], that may minimize light scattering and shorten the propagation path within the composite. This reduction in scattering intensity might result in a less perceptible overall color change, enhancing the material\u0026rsquo;s aesthetic stability[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Meanwhile, the composition of staining solutions has chance to influence outcomes. The acidity of cola may potentially weaken the filler-matrix interface in P60 composites due to hydrolysis of silane coupling agents, which could contribute to increased chromatic divergence compared to Z350. Conversely, the tannic acid and polyphenols in coffee or iced tea appear to interact preferentially with Z350 surfaces, potentially through hydrogen bonding with Si-OH groups, which may lead to comparatively more noticeable color discrepancies than those seen with P60 surfaces[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Therefore, for high esthetic requirement patients, Z250 should be used with caution due to its susceptibility to unacceptable color changes after exposure to common beverages. Z350 and P60 offer better color stability thanks to their filler structures. Clinicians should match dental resin materials with patients\u0026rsquo; beverage consumption habits. For patients who frequently drink cola, it is advisable to choose alternatives to Z350 due to potential degradation risks in P60 and encourage them to reduce cola intake. Similarly, for those who regularly consume iced tea, refrain from using Z350, and suggest limiting intake of these beverages.\u003c/p\u003e \u003cp\u003eThe immediate SBS results of all the three materials exceeded the clinically required range (6\u0026ndash;8 MPa)[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e], while Z250 showing the lowest strength, that may due to its lower filler ratio resulting in insufficient material rigidity and propensity to develop stress concentration points, predisposing cohesive failure. Simultaneously, the elevated matrix content within Z250 predisposes the material to intensified polymerization shrinkage stress, which mechanistically induces micrometer-scale interfacial cracks at the resin-enamel junction through anisotropic contraction patterns, thereby compromising SBS to some extent. Z350\u0026rsquo;s nanofiller arrangement displays enhanced rigidity than Z250, that achieve optimal SBS with compatible bonding agents[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. P60\u0026rsquo;s hybrid fillers and highly crosslinked matrix tend to exhibit relatively superior inherent rigidity and comparatively minimal polymerization shrinkage, which may contribute to satisfactory mechanical hardness performance. The ARI analysis revealed a predominant incidence of ARI score 0 in Z250 group, indicating a feasible monolithic debonding through bulk removal using a needle holder. It appears to reduce chairside time and minimize enamel damage. Conversely, Z350/P60 groups showed higher ARI scores suggesting difficulty in attachment removal, where controlled grinding protocols using high-speed turbines avoid catastrophic interfacial delamination-induced enamel fractures observed in direct peel-off methods.\u003c/p\u003e \u003cp\u003eIn the durability testing, P60 exhibited the lowest roughness and wear volume, outperforming Z250 and Z350. These differences may be attributed to variations in filler characteristics, including size, shape, content, orientation, and distribution within the composite resin[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. The observed superior wear resistance of P60 during wear cycles may be associated with its higher filler loading and potentially optimized filler-matrix coupling, demonstrating enhanced mechanical strength[\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. P60\u0026rsquo;s filler size and orientation, enabling uniform stress distribution and a \u0026ldquo;self-polishing\u0026rdquo; mechanism, forming enamel-like smooth surfaces. Its lower resin matrix content simultaneously appears to prevent localized excessive matrix abrasion. Conversely, Z250/Z350\u0026rsquo;s higher resin matrix content more likely lead to preferential matrix wear, exposing fillers and increasing roughness. Specifically, Z250\u0026rsquo;s micrometer-filler seems to create relatively heightened surface roughness post-wear compared to nanoscale-filled Z350. In clinical condition, P60\u0026rsquo;s relatively smooth surface after wear may reduce bacterial biofilm formation on the material surface to a certain extent[\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e], which is beneficial for maintaining oral hygiene and enamel health. Additionally, its small wear defect volume might indicate minimal wear deformation during aligner insertion and removal, which is advantageous for long-term force application and stability in CAT.\u003c/p\u003e \u003cp\u003eAfter the aging test, particularly treated with thermal cycling, all three materials demonstrated increased SBS, that may attribute to the post-curing effect of light-activated resins. It was likely Z250 had a lower initial resin matrix crosslinking degree, which increased significantly during aging, densifying its structure and boosting SBS. In comparison, Z350 and P60 had higher initial crosslinking, with less aging-induced change. Thus, Z250\u0026rsquo;s substantial SBS improvement bridged the gap, eliminating group differences. Hydroplasticization mediated by water-sorption phenomena facilitates a brittle-to-ductile transition in resin matrices through plasticizer-like molecular interactions, appears to enhance fracture resistance. Simultaneously, Ca\u0026sup2;⁺ and PO₄\u0026sup3;⁻ ions in artificial saliva may deposit hydroxyapatite-like microlayers in ideal condition, filling micro cracks and reinforcing resin-enamel interfaces[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. These findings suggest that restorations exhibit reduced risk of debonding during clinical aging.\u003c/p\u003e \u003cp\u003eOverall, P60 demonstrated an outstanding overall performance, while clinical observations indicate that it demonstrates limited adoption in routine practice. Z250 and Z350 remain predominant choices among prosthodontists and orthodontists based on empirical surveys. This may be because resins have traditionally been used for restoration, which emphasizes precise color matching. Therefore, Z350 and Z250 are more popular due to their broader shade selection. However, the application scenarios of orthodontic attachment differ from those of restorative resins. Aligner attachments are mostly used on posterior teeth, and even when used on anterior teeth, they are only applied temporarily or in small areas, resulting in less stringent requirements for shade aesthetics compared to restorative procedures. As such, P60\u0026rsquo;s overall performance is more suitable for orthodontic attachments. This study not only provides evidence-based support for challenging conventional material application norms but also provides clinical guidance for selecting attachment materials. It is suggested that clinicians prioritize P60 when seeking an optimal balance between functionality and aesthetics, employ Z350 to meet higher aesthetic requirements with more color options, and consider Z250 as an economical alternative.\u003c/p\u003e \u003cp\u003eNevertheless, our work retains limitations characteristic of \u003cem\u003ein vitro\u003c/em\u003e methodologies, including incomplete simulation of critical oral environmental factors such as dynamic pH fluctuations, bacterial biofilm interactions, and salivary enzyme activity[\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. To establish robust clinical correlations, future investigations should incorporate in \u003cem\u003evivo\u003c/em\u003e analyses coupled with controlled clinical trials, thereby validating material performance under physiologically relevant multi-factor oral environments.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThis study conclusively rejected the null hypothesis, demonstrating statistically significant variations in color stability, SBS, and durability across the tested materials. Z250 underperformed than Z350 and P60 in terms of color stability, shear bond strength, and durability tests. Z350 exhibits superior aesthetic properties and achieves effective bonding through higher SBS, however, the predominant presence of adhesive remnant at the failure interface indicates that direct interfacial delamination poses a higher risk of enamel damage, whereas meticulous removal using a high-speed turbine handpiece can mitigate such iatrogenic risks. P60 excels with clinically acceptable color stability, residual adhesive remnants and exceptional wear resistance, suggesting superior suitability for common orthodontic attachments requiring long-term functional durability and aesthetic preservation. Clinical decision-making should be guided by a three-dimensional framework encompassing aesthetic demand intensity, treatment duration, and cost sensitivity, prioritizing P60 to achieve an optimal balance between function and aesthetic. Targeted application of Z350/Z250 is recommended for specific clinical scenarios, complemented by standardized bonding protocols and patient behavior management to optimize treatment outcomes.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e \u003cp\u003e This study was approved by the medical ethics committee of the Affiliated Stomatology Hospital of Nanchang University, China, Ethics Approval Number: (Ethical Review of Dentistry 2024 No. (084)). The use of human tissue samples was performed in accordance with relevant guidelines and regulations. All methods were carried out in accordance with the principles of the Declaration of Helsinki. Written informed consent was obtained from all participants prior to inclusion in this study. The consent process included detailed explanations of research objectives, procedures, risks, and benefits, and participants retained the right to withdraw at any stage.\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eClinical trial number\u003c/h2\u003e \u003cp\u003eNot applicable.\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eConsent for publication\u003c/h2\u003e \u003cp\u003eNot applicable.\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eCompeting interests\u003c/h2\u003e \u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eAuthors\u0026rsquo; information\u003c/h2\u003e \u003cp\u003e \u003csup\u003e1\u003c/sup\u003e School of Stomatology, Jiangxi Medical College, Nanchang University, Nanchang, 330000, Jiangxi, China.\u003c/p\u003e \u003cp\u003e \u003csup\u003e2\u003c/sup\u003e Jiangxi Provincial Key Laboratory of Oral Diseases and Jiangxi Provincial Clinical Research Center for Oral Diseases, Nanchang, 330000, Jiangxi, China.\u003c/p\u003e \u003cp\u003e \u003csup\u003e3\u003c/sup\u003e Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong S.A.R., China.\u003c/p\u003e \u003cp\u003e \u003csup\u003e4\u003c/sup\u003e Department of Stomatology, Liuzhou Worker\u0026rsquo;s Hospital, Liuzhou, 545000, Guangxi Zhuang Autonomous Region, China.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThis work was supported by the National Natural Science Foundation of China [grant number 82460186].\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eYunlin Guan: Methodology, Writing-Original Draft, Software, Formal analysis, Investigation, Visualization, Validation. Jiarong Xu: Methodology, Validation, Investigation, Formal analysis. Junhong Qiu: Methodology, Software, Visualization. Hao Cai: Methodology, Data Curation.Wenxuan Xia: Methodology, Visualization. Zhou Ye: Data Curation, Supervision, Resources, Writing-Editing.Ting Sang: Conceptualization, Methodology, Visualization, Resources, Supervision, Data Curation, Writing-Editing.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e \u003cp\u003eNot applicable.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe data supporting the findings of this study are available from the corresponding author upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eNarongdej P, Hassanpour M, Alterman N, Rawlins-Buchanan F, Barjasteh E. Advancements in clear aligner fabrication: A comprehensive review of direct-3D printing technologies. Polymers. 2024;16:371.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAlMogbel A. Clear Aligner Therapy: Up to date review article. J Orthod Sci. 2023;12:37.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTamburrino F, D\u0026rsquo;Ant\u0026ograve; V, Bucci R, Alessandri-Bonetti G, Barone S, Razionale AV. Mechanical properties of thermoplastic polymers for aligner manufacturing: In vitro study. Dentistry J. 2020;8:47.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBichu YM, Alwafi A, Liu X, Andrews J, Ludwig B, Bichu AY, et al. Advances in orthodontic clear aligner materials. Bioactive Mater. 2023;22:384\u0026ndash;403.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCenzato N, Di Iasio G, Mart\u0026igrave;n Carreras-Presas C, Caprioglio A, Del Fabbro M. Materials for clear aligners\u0026mdash;a comprehensive exploration of characteristics and innovations: A scoping review. Appl Sci. 2024;14:6533.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYu X, Li G, Zheng Y, Gao J, Fu Y, Wang Q, et al. Invisible\u0026rsquo; orthodontics by polymeric \u0026lsquo;clear\u0026rsquo; aligners molded on 3D-printed personalized dental models. Regenerative Biomaterials. 2022;9:rbac007.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAhmad W, Jiang F, Xiong J, Xia Z. The mechanical effect of geometric design of attachments in invisible orthodontics. Am J Orthod Dentofac Orthop. 2023;164:183\u0026ndash;93.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAkhtar K, Pervez C, Zubair N, Khalid H. Calcium hydroxyapatite nanoparticles as a reinforcement filler in dental resin nanocomposite. J Mater Sci - Mater Med. 2021;32:129.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSaini RS, Binduhayyim RIH, Gurumurthy V, Alshadidi AAF, Aldosari LIN, Okshah A, et al. Dental biomaterials redefined: Molecular docking and dynamics-driven dental resin composite optimization. BMC Oral Health. 2024;24:1\u0026ndash;18.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDonmez MB, \u0026Ccedil;akmak G, Yılmaz D, Schimmel M, Abou-Ayash S, Yilmaz B et al. Bond strength of additively manufactured composite resins to dentin and titanium when bonded with dual-polymerizing resin cements. J Prosthet Dent. 2023;:S0022-3913(23)00255-X.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eA F da VJ JC, de F CE. Surface wear and adhesive failure of resin attachments used in clear aligner orthodontic treatment. J Orofac Orthop. 2024;85 Suppl 1.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCao L, Zhao X, Gong X, Zhao S. An in vitro investigation of wear resistance and hardness of composite resins. Int J Clin Exp Med. 2013;6:423\u0026ndash;30.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEr\u0026ccedil;in \u0026Ouml;, Kurnaz M, Kopuz D. Evaluation of the color stability of attachments made with different resin composites. Am J Orthod Dentofac Orthop. 2023;164:e121\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKircelli BH, Kilinc DD, Karaman A, Sadry S, Gonul EY, G\u0026ouml;gen H. Comparison of the bond strength of five different composites used in the production of clear aligner attachments. J Stomatology Oral Maxillofacial Surg. 2023;124:101481.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePazinatto FB, Gionordoli Neto R, Wang L, Mondelli J, Mondelli RFL. Navarro MF de L. 56-month clinical performance of class I and II resin composite restorations. J Appl Oral Sci. 2012;20:323\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCatal\u0026aacute;n A, Mart\u0026iacute;nez A, Mu\u0026ntilde;oz C, Medina C, Marzialetti T, Monta\u0026ntilde;o M, et al. The effect of preheating of nano-filler composite resins on their degree of conversion and microfiltration in dental fillings. Polym Bull. 2022;79:10707\u0026ndash;22.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChen W, Qian L, Qian Y, Zhang Z, Wen X. Comparative study of three composite materials in bonding attachments for clear aligners. Orthod Craniofac Res. 2021;24:520\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLuo MR, Cui G, Rigg B. The development of the CIE 2000 colour-difference formula: CIEDE2000. Color Res Appl. 2001;26:340\u0026ndash;50.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYassaei S, Davari A, Goldani Moghadam M, Kamaei A. Comparison of Shear Bond Strength of RMGI and Composite Resin for Orthodontic Bracket Bonding. J Dent (Tehran). 2014;11:282\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePeng S, Sang T, Wang H, Guan Y, Deng Y, Wang P, et al. Bioinspired anti-demineralization enamel coating for orthodontics. J Dent Res. 2022;101:1620\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMoussa DG, Fok A, Aparicio C. Hydrophobic and antimicrobial dentin: A peptide-based 2-tier protective system for dental resin composite restorations. Acta Biomater. 2019;88:251\u0026ndash;65.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAbdallah M-N, Light N, Amin WM, Retrouvey J-M, Cerruti M, Tamimi F. Development of a composite resin disclosing agent based on the understanding of tooth staining mechanisms. J Dent. 2014;42:697\u0026ndash;708.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLi Q, Zhan N, Ng T, Swain MV, Wan B, Jian Y, et al. The influence of hygroscopic expansion of resin supporting dies on the fracture resistance of ceramic restorations during thermal cycling. Dent Mater. 2024;40:1231\u0026ndash;43.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eOivanen M, Keulemans F, Garoushi S, Vallittu PK, Lassila L. The effect of refractive index of fillers and polymer matrix on translucency and color matching of dental resin composite. Biomater Investig Dent 8:48\u0026ndash;53.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGonulol N, Ozer S, Sen Tunc E. Water sorption, solubility, and color stability of giomer restoratives. J Esthet Restor Dent. 2015;27:300\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKircelli BH, Kilinc DD, Karaman A, Sadry S, Gonul EY, G\u0026ouml;gen H. Comparison of the bond strength of five different composites used in the production of clear aligner attachments. J Stomatology Oral Maxillofacial Surg. 2023;124:101481.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRodr\u0026iacute;guez HA, Kriven WM, Casanova H. Development of mechanical properties in dental resin composite: Effect of filler size and filler aggregation state. Mater Sci Engineering: C. 2019;101:274\u0026ndash;82.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBi\u0026ccedil;er Z, Yaman BC, \u0026Ccedil;eliks\u0026ouml;z \u0026Ouml;, Tepe H. Surface roughness of different types of resin composites after artificial aging procedures: An in vitro study. BMC Oral Health. 2024;24:876.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKakuta K, Wonglamsam A, Goto S-I, Ogura H. Surface textures of composite resins after combined wear test simulating both occlusal wear and brushing wear. Dent Mater J. 2012;31:61\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChoi S, Jo Y-H, Luke Yeo I-S, Yoon H-I, Lee J-H, Han J-S. The effect of surface material, roughness and wettability on the adhesion and proliferation of \u003cem\u003estreptococcus gordonii\u003c/em\u003e, \u003cem\u003efusobacterium nucleatum\u003c/em\u003e and \u003cem\u003eporphyromonas gingivalis\u003c/em\u003e. J Dent Sci. 2023;18:517\u0026ndash;25.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJu K, Zhao Z, Chen X, Liu X, Li J. Preparation and growth behaviours of low porosity hydroxyapatite with enhanced adhesion by electrochemical deposition on micro-arc oxide coatings. Surf Coat Technol. 2023;473:130017.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAlhotan A, Raszewski Z, Alamoush RA, Chojnacka K, Mikulewicz M, Haider J. Influence of Storing Composite Filling Materials in a Low-pH Artificial Saliva on Their Mechanical Properties\u0026mdash;An In Vitro Study. J Funct Biomaterials. 2023;14:328.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"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":"clear aligner, composite attachment, color stability, shear bond strength, durability","lastPublishedDoi":"10.21203/rs.3.rs-6736420/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6736420/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e As clear aligner technology (CAT) gains prominence, the performance of composite attachments - critical devices for optimizing aligner retention and tooth movement control - require systematic evaluation. This study assesses three light-cured composites (Filtek™ Z250 XT, Z350 XT, and P60; 3M ESPE) regarding color stability, shear bond strength (SBS), and durability to establish evidence-based selection criteria.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e Attachments were bonded to mandibular premolars, simulating the clinical process, and materials were tested for color changes (after immersion in coffee, cola, or iced tea), SBS, and durability (wear volume, surface roughness, morphology, post-aging SBS). The data obtained from the study were statistically evaluated via the Shapiro-Wilk test, the Levene test, t-tests, one-way analysis of variance and chi-square test. A \u003cem\u003ep\u003c/em\u003e-value \u0026lt; 0.05 was considered statistically significant.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e Z250 showed significantly higher coffee - induced discoloration than Z350\u003cem\u003e \u003c/em\u003e(\u003cem\u003ep \u003c/em\u003e\u0026lt; 0.05) and P60\u003cem\u003e \u003c/em\u003e(\u003cem\u003ep \u003c/em\u003e\u0026lt; 0.01), exceeding clinical acceptability (ΔE\u003csub\u003e00\u003c/sub\u003e ≥ 3.3). Z250 also\u003cstrong\u003e \u003c/strong\u003eemerged similar trends with cola and iced tea. Z350 exhibited the highest immediate SBS (\u003cem\u003ep \u003c/em\u003e\u0026lt; 0.05 vs. Z250) that may cause enamel damage. P60 demonstrated superior wear resistance, with significantly lower surface roughness (Sq / Sa) than Z250 (\u003cem\u003ep \u003c/em\u003e\u0026lt; 0.001) and Z350 (\u003cem\u003ep \u003c/em\u003e\u0026lt; 0.01), and the smallest post-wear defect volume (\u003cem\u003ep \u003c/em\u003e\u0026lt; 0.01 vs. Z250). The SBS differences in immediate groups were eliminated through aging treatment\u003cem\u003e.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e Z250 underperformed in color stability, SBS, and durability versus Z350/P60, though demonstrated cost-effectiveness. Z350 offers outstanding color durability and higher SBS but risks enamel damage from interfacial delamination. P60 excels with color stability, acceptable adhesive remnants, and exceptional wear resistance, serving diverse clinical needs. Clinical decisions could prioritize P60 for function-aesthetic balance, with targeted Z350/Z250 use in special scenarios.\u003c/p\u003e","manuscriptTitle":"Multiparametric performance comparison of dental composites for clear aligner attachments","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-16 11:54:18","doi":"10.21203/rs.3.rs-6736420/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-06-19T12:35:02+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-18T19:18:41+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-17T06:47:05+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"339305309462451542267229426655012060199","date":"2025-06-12T20:36:45+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"301877512617747142126862433536255248598","date":"2025-06-12T05:27:47+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-06-12T03:03:17+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-06-12T03:01:24+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-06-03T09:48:39+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-06-03T05:11:40+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Oral Health","date":"2025-06-03T05:08:36+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":"3f96bfec-b6b6-4341-8f2e-b2deae7b9b92","owner":[],"postedDate":"June 16th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-08-07T07:13:04+00:00","versionOfRecord":{"articleIdentity":"rs-6736420","link":"https://doi.org/10.1186/s12903-025-06623-w","journal":{"identity":"bmc-oral-health","isVorOnly":false,"title":"BMC Oral Health"},"publishedOn":"2025-07-19 16:05:35","publishedOnDateReadable":"July 19th, 2025"},"versionCreatedAt":"2025-06-16 11:54:18","video":"","vorDoi":"10.1186/s12903-025-06623-w","vorDoiUrl":"https://doi.org/10.1186/s12903-025-06623-w","workflowStages":[]},"version":"v1","identity":"rs-6736420","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6736420","identity":"rs-6736420","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}