Influence of Printing Orientation on Mechanical Characteristics of NextDent Biocompatible Resin in SLA 3D Printing

Influence of Printing Orientation on Mechanical Characteristics of NextDent Biocompatible Resin in SLA 3D Printing | 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 Influence of Printing Orientation on Mechanical Characteristics of NextDent Biocompatible Resin in SLA 3D Printing Himanshu Bisaria, Rahul Jibhakate, Sushil Kumar Singh, Samarjit Singh This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4627463/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The use of 3D printing in dentistry has revolutionized the manufacturing of dental prosthetics and devices. This research focuses on examining the mechanical properties of NextDent dental resins when processed through 3D printing. A variety of mechanical tests, including tensile, fracture, flexural testing, and impact testing are performed on specimens printed using NextDent resins. The thermo-mechanical and thermal behavior of the resin was assessed using Dynamic Mechanical Analysis and Thermogravimetric Analysis testing respectively. The specimens are fabricated at different printing angles, including 0º (vertical), 30º, 60º, and 90º (horizontal), to assess the impact of printing orientation on the mechanical properties. The mechanical properties were found superior at 0º (vertical) followed by 30º 60º & 90º. Fourier-transform infrared spectroscopy (FT-IR) analysis revealed the resin's molecular composition, including C-H, C = C, O-H, N-H, C-N, and C = O stretching and bending vibrations, indicating functional groups, suggesting bromine-containing compounds. DMA test’s result showed a storage modulus of 1575 MPa at room temperature, with a glass transition temperature (Tg) of 107°C, suggesting good damping properties. NextDent resin 3D printing mechanical properties printing angle tensile testing flexural testing fracture testing TGA DMA FT-IR Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 1. Introduction Stereolithography (SLA), a form of 3D printing additive manufacturing, finds extensive use across various industries, notably in biomedical applications [1]. SLA based additive manufacturing involves vat photopolymerization technology to create solid objects by the process of photopolymerization of vat of liquid resin using laser. Vat photopolymerization is superior to other additive manufacturing (AM) technologies, for example selective laser sintering (SLS) and fused deposition modeling (FDM) due to its ability to fabricate intricate complex parts with high speed, spatial resolution and precision [2]. Presently, SLA and FDM are engaged in direct competition, primarily due to the initial high cost of resin and the increasing number of SLA providers, resulting in a decline in resin prices. As 3D printing doesn't need cutting or grinding metal, it provides a great deal of design and geometric freedom to the manufacturers to meet industrial requirements beyond the conventional fabrication methods [3]. Besides offering flexibility in shapes, additive manufacturing methods can integrate various materials in one item, enabling users to switch materials during printing for intricate combinations, resulting in customized mechanical and design attributes not achievable through traditional manufacturing methods. It has transitioned from being solely a prototyping tool to being employed in the production of consumer-ready goods [4]. Companies are increasingly drawn to 3D printed products due to their minimized energy consumption and waste generation [5]. In the realm of biomedicine, 3D printed technology has been found to be the most effective owing to the possibility of fabrication of patient specific customized products. In dentistry, the use of AM techniques has been generally accepted for sophisticated treatment planning, making orthodontic and bite splints, and making surgical drill guides. It is essential that surgical guidelines for oral implantology are made precisely [6]. Various parameters have been explored to observe the impact of printing pathways on mechanical properties. Increasing layer thickness reduces printing time but deteriorates the surface finish [7, 8]. In SLA, post-curing creates inter-layer linkages resulting in a smooth surface finish without visible layer interfaces [9]. The strength of the material is also influenced by changes in the infill parameter. Many scholars have investigated how different build settings affect the mechanical properties of polymer materials using various 3D printing techniques [10]. Song et al. [11] inspected the mechanical response of unidirectional 3D-printed Polylactic acid (PLA) by conducting a series of tensile, compressive, and flexural tests. Their study revealed significant anisotropy in mechanical properties due to the printing orientation and layer bonding. Key findings included the higher strength and stiffness along the printing direction and the notable impact of layer adhesion on the material's overall mechanical performance. Wang et al. [12] focused on enhancing PLA’s impact strength in fused layer modeling (FLM) through material modifications. They experimented with various additives and processing conditions to improve the toughness of PLA. The study found that specific additives significantly increased the impact resistance of PLA without compromising its printability, demonstrating a viable method to produce more durable 3D-printed PLA parts. Cantrell et al. [13] experimentally characterized the mechanical properties of 3D-printed parts made-up of Polycarbonate and Acrylonitrile butadiene styrene (ABS). They performed compressive, tensile, and flexural tests to assess the materials' strength, stiffness, and failure modes. The study exposed that polycarbonate generally exhibited superior mechanical properties compared to ABS, and that both materials' properties were significantly affected by layer orientation and infill density. Ankouhi et al. [14] conducted mechanical characterization and failure analysis of 3D-printed ABS, focusing on the effects of printing orientation and layer thickness. Through tensile and impact testing, they found that thinner layers and optimized orientation significantly enhanced the mechanical performance and failure resistance of ABS parts. The study concluded that careful selection of printing parameters is crucial for maximizing the strength and durability of 3D-printed components. Torrado and Roberson [15] analyzed the failure and anisotropy of tensile test specimens with varying print raster patterns and geometries. Their evaluation, involving tensile testing, indicated that both specimen geometry and raster pattern significantly influence the mechanical properties and failure behavior. The study highlighted that certain print patterns and geometries can mitigate anisotropy, leading to more uniform strength and improved performance in 3D-printed parts. Durgun and Ertan [16] conducted an experimental investigation of the Fused Deposition Modeling (FDM) technique to enhance mechanical properties while considering production cost. Through systematic experimentation and analysis, they identified optimal process parameters that improved mechanical strength without significantly increasing production expenses. Their findings contribute valuable insights into optimizing FDM for cost-effective yet high-performance 3D printing applications. Sood et al. [17, 18] conducted a comprehensive investigation into the mechanical properties of FDM parts. The study involved a parametric appraisal to understand how different printing parameters affect mechanical properties. They performed experimental investigations and developed empirical models specifically aimed at enhancing compressive strength through optimized FDM processing. Lee et al. [19] measured the anisotropic compressive strength of AM parts. Through their study, they assessed how the orientation of the printed layers affects the compressive strength of the parts. Vega et al. [20] investigated the influence of layer orientation on both microstructure and mechanical properties of a polymer. Through their study, they examined how different printing orientations affect the material's mechanical performance and internal structure. This research contributes to a deeper understanding of how printing parameters impact the final properties of 3D-printed parts, providing valuable insights for optimizing printing processes and material selection. Rao et al. [21] explored the influence of conventional drilling and additive fabrication techniques on the tensile properties of 3D-printed ONYX/CGF composites. Their study investigated how different methods of creating holes within the composites affect their mechanical behavior. By comparing conventionally drilled holes to additively fabricated ones, the research provides insights into optimizing manufacturing processes for composite materials, offering potential enhancements in strength and performance. It likely includes experimental comparisons of tensile strength and modulus between specimens with these different hole fabrication methods, aiming to optimize composite performance. Compared to traditional fabrication techniques, SLA-printed surgical guides are purported to enhance the precision of implant positioning. Even with drill guides, achieving a fully predictable implant position isn't guaranteed. Surgical guidelines printed via SLA exhibited discrepancies of up to 13% from the intended design. These errors primarily stem from data manipulation by the operator or irregular fitting of the surgical guide. Notably, the latter issue may indicate inaccuracies in the fabrication process of SLA-printed surgical guides [22].The precision of SLA printing can be influenced by both the printing process itself and the characteristics of the photosensitive resins employed. While SLA printing typically involves preset parameters like printing speed, cured line width, energy distribution, and cure depth, certain preprocessing settings such as configuring supporting structures, positioning objects on the build platform, and determining object orientation must be adjusted. Additionally, operators have control over post-processing steps like washing, cleaning, and final polymerization, all of which can impact the precision and mechanical properties of the produced parts. Variations in both pre- and post-processing procedures may affect the accuracy and mechanical characteristics of the final product [23]. The stability of surgical drill guides during use is crucial to prevent fracture and bending. Studies have shown that different printing directions can influence the mechanical properties of various SLA materials. A new class I biocompatible resin designed for surgical guide production has recently been introduced and utilized in clinical settings for tasks such as implant placement and sinus grafting [24]. However, for this particular resin type, the manufacturer provides specifications for flexural properties but lacks information regarding the effects of printing process parameters on these properties. From the literature review, it can be summarized that there is currently no existing research that explores the utilization of this specific resin in SLA manufacturing to analyze how processing settings impact accuracy and mechanical properties. Therefore, this study aims to investigate the effects of print orientation, part placement on the build platform, and post-curing processes on the mechanical properties of SLA-produced items. Tensile, flexural, fracture and impact test were conducted for mechanical analysis. Thermogravimetric Analysis (TGA) and Dynamic Mechanical Analysis (DMA) tests were conducted for analyzing the thermal stability and thermo-mechanical behavior of resin respectively. For identifying chemical compound, FT-IR test of resin was also performed. The information gathered can guide dental professionals in optimizing printing parameters and design considerations for specific dental applications, ensuring the fabrication of high-quality and durable dental prosthetics and devices. 2. Materials and Methodology In this study, samples intended for dental surgical guides in implant surgery were crafted using a biocompatible class I “NextDent” SG (surgical guide) resin This material is specifically engineered for high-precision dental 3D printing applications, ensuring its suitability and efficacy for implant procedures. Identified by its translucent orange color, the resin's specifications and properties, as determined from testing, are outlined in Table 1 . The samples were produced using the UltraOne, a high-resolution 4K desktop 3D printer manufactured by U3DS (Utpal 3D Systems). With support for layer heights from 0.025 mm to 0.2 mm and a spacious printing area of 120 × 68 × 200 mm, this printer caters to various applications, particularly those utilizing 405 nm resins. Specimen models were designed using CAD software and saved in the STL (Stereolithography) file format. These models were then imported into Chitubox software for slicing and G-code generation. To investigate the impact of printing orientation on mechanical properties, specimens were printed at four orientations: 0°, 30°, 60°, and 90° as shown in Fig. 1 . Various mechanical tests, including flexural, tensile, fracture, and impact assessments, were conducted on these samples. The details of characterizations of 3D printed samples are summarized in Table 2 . The 3D-printed specimens, as depicted in Fig. 2 , underwent cleaning with ethanol to remove excess resin before testing. Subsequently, to ensure optimal polymer conversion, they were cleaned, dried, and post-cured using UV radiation. Table 1 Properties of the NextDent SG resin used for 3D printing Property Result Requirement Standard Ultimate Flexural Strength 85 ≥ 50 MPa ISO 20795-1 Glass transition temperature ( T g ) 107°C - ASTM 5418 Flexural Modulus 2118 ≥ 1500 MPa ISO 20795-1 Biocompatibility Comply Non-cytotoxic ISO 10993-1 Residual monomer < 0.1 ≤ 2.2% (w/w) ISO 20795-1 Biocompatibility Comply Not a sensitizer - ISO 10993-1 Compounds C = O stretching vibrations O-H stretching C-N stretching C-H stretching - ASTM E1252-98/ E168-06 Biocompatibility Comply Non-mutagenic ISO 10993-1 Storage modulus (GPa) 1.575 - ASTM 5418 Table 2 Details of test performed on 3D printed samples Test Equipment Standard Specimen Dimensions Conditions Measured Parameters FT-IR PerkinElmer Spectrum 3 ASTM E1252-98/E168-06 - Wavenumber range: 400 to 4000 cm − 1 Chemical composition DMA DMA Q800 ASTM 5418 50 × 13 × 3 mm 3 Bending mode frequency: 1 Hz, Temperature range: Room temp to 200°C Heating rate: 10°C/min, Damping, loss modulus, storage modulus TGA TGA Q50 ASTM E 1131 15–25 mg Temperature range: 30°C to 800°C, N 2 flow: 20 mL/min, Heating rate: 10°C/min Thermal stability Tensile Instron 3382 UTM ASTM D-638 (Type-V) 9.53 mm (total length), 7.62 mm (gauge length), 3.18 mm (width), 3.2 mm (thickness) Strain rate: 5 mm/min, Temperature: Ambient Tensile strength Flexural Instron 3382 UTM ASTM D-790 58 mm (length), 12 mm × 2.7 mm (cross-section) Span length: 45 mm, Load rate: 1.30 mm/min Flexural strength, flexural modulus Impact Izod impact tester (Tinius Olsen) ASTM D 256 63.5 × 12.7 × 5 mm 3 - Impact strength Fracture Instron 3382 UTM ASTM D5045-14 48 mm (span length), 6 mm (thickness), 12 mm (breadth), 6 mm (crack length) Cross head speed: 0.5 mm/min Critical energy release rate (G IC ), Fracture toughness (K IC ), 3. Results and Discussion 3.1 FT-IR The FT-IR analysis of the resin unveiled several prominent absorption peaks indicative of its chemical composition and molecular structure. As depicted in Fig. 3 , the FT-IR graph of the resin showcased a broad peak at 3377.47 cm − 1 , suggesting the incidence of O-H stretching vibrations characteristic of alcohols or phenols. Furthermore, peaks observed at 2924.20 cm − 1 , 1451.83 cm − 1 , 1406. cm − 1 , and 1382.54 cm − 1 linked to C-H stretching and bending vibrations in alkanes, further indicating the presence of hydrocarbon moieties within the resin. Notably, peaks at 1717.96 cm − 1 and 1653.71 cm − 1 signified C = O stretching vibrations, potentially originating from carbonyl groups present in esters or carboxylic acids. The spectrum also exhibited multiple peaks associated with C = C stretching vibrations in aromatic rings, including those at 1607.97 cm − 1 , 1560.33 cm − 1 , 1508.38 cm − 1 , and 1244.84 cm − 1 . Moreover, characteristic vibrations of amine groups were detected, such as N-H bending at 1541.40 cm − 1 and C-N stretching at 1295.67 cm − 1 , 1130.22 cm − 1 , and 1062.27 cm − 1 , suggesting the presence of aromatic and aliphatic amine functionalities. Furthermore, the presence of bromine-containing compounds was indicated by peaks around 589.22 cm − 1 and 574.58 cm − 1 , agreeing to C-Br stretching vibrations in alkyl bromides. 3.2 DMA Dynamic Mechanical Analysis (DMA) tests were conducted at an oscillating frequency of 1Hz to explore the dynamic storage modulus (E') and loss factor (tanδ) of 3D-printed epoxy specimens [25]. Figure 4 displays the storage modulus variation concerning temperature. At room temperature, the pure epoxy exhibited a storage modulus of 1575 MPa. An essential property of thermosetting polymers is the glass transition temperature (Tg), representing the shift from a glassy to a rubbery state. In this investigation, Tg values corresponded to peaks in the damping factor (Tan δ) curves. The ratio of E'' to E', indicating the energy dissipated as heat per cycle, defines the damping capability or the material's ability to absorb vibration energy. Typically, temperatures where Tan δ exceeds 0.3 denote good damping properties. For the 3D-printed epoxy specimens, the glass transition temperature (Tg) was identified as 107°C. 3.3 TGA Figure 5 illustrates the temperature-dependent weight loss behavior of SG resin. TGA curve divulges three different zones of weight loss as the temperature upsurges. The initial weight loss of approximately 5% is observed in resin at temperatures of 286ºC. The initial weight loss observed is primarily attributed to the removal of moisture content present in the composites. As the temperature further increases, a substantial weight loss of around 69.58% is observed. This significant weight reduction occurs at higher temperatures and is likely associated with the degradation and decomposition of the composite constituents. The max. weight loss rate (%/ºC) was 1.333 at temperature 432.19°C. 3.4 Tensile properties The tensile strength (TS) of the specimens varies significantly with the printing orientation. As depicted in the Fig. 6 , the highest tensile strength is observed in specimens printed at 0º (E0 orientation). As the printing angle increases, there is a gradual decrease in tensile strength, with the lowest value recorded for specimens printed horizontally at 90º (E90 orientation). Similarly, the tensile modulus (TM) shows a decreasing trend as the printing angle increases. Specimens printed at 0º exhibit the highest tensile modulus, while those printed horizontally at 90º demonstrate the lowest tensile modulus. The tensile strength (TS) at a 0º printing angle was observed to be higher by 15.49%, 25.88%, and 43.53% respectively compared to the 30º, 60º, and 90º printing angles. Similarly, the tensile modulus (TM) at a 0º printing angle was found to be higher by 15.18%, 36.02%, and 51.42% respectively compared to the 30º, 60º, and 90º printing angles. The reduction in tensile properties is likely due to decreased interlayer adhesion and misalignment of print layers with the load direction as the printing angle deviates from the vertical orientation. Previous research has observed a significant influence of print layer orientation on the mechanical properties of 3D-printed specimens. Horizontal printing (90º) typically results in lower mechanical qualities compared to vertical printing (0º), which often yields the highest tensile strength and modulus. These findings emphasize the importance of selecting the appropriate printing angle to optimize the desired mechanical performance of 3D-printed components. To fully understand the relationship between printing parameters and mechanical properties, future studies should investigate additional factors such as infill density, layer height, and printing speed. 3.5 Flexural properties The flexural strength increases significantly as the printing angle increases as represented in Fig. 7 . The specimens printed at a 90º angle (E90) exhibit the highest flexural strength followed by those printed at a 60º angle (E60), 30º (E30) and 0º (E0). Similarly, the flexural modulus follows a similar trend of increasing with the printing angle. The flexural strength (FS) at a 0º printing angle was higher by approximately 19.02%, 67.51%, and 216.26% compared to the 30º, 60º, and 90º printing angles, respectively. Similarly, the flexural modulus (FM) at a 0º printing angle exhibited a higher percentage increase of about 53.38%, 150.66%, and 206.47% compared to the 30º, 60º, and 90º printing angles, respectively. Printing at steeper angles allows for better alignment of the printed layers with the bending load direction, resulting in improved load distribution and enhanced resistance to bending forces. Consequently, specimens printed at 90º exhibit the highest flexural properties, while those printed vertically (0º) display the lowest. Printing objects horizontally (90º) optimizes load distribution, minimizing shear stresses and enhancing cohesive strength, while maximizing load-bearing capacity compared to vertical printing (0º). Additionally, the longer span of printed layers in the cross-section further improves flexural properties through enhanced interlayer adhesion and structural integrity. 3.6 Impact properties The effect of printing angles on impact strength and impact energy of 3D printed samples is illustrated in Fig. 8 . As the printing angle increases from 0º to 90º, there is a decreasing trend in impact strength and impact energy, with specimens printed at 90º (E90) exhibiting the lowest impact strength. At 0º printing angle, the impact strength was notably higher by approximately 11.59%, 23.73%, and 25.96% compared to the 30º, 60º, and 90º printing angles, respectively. Similarly, the impact energy (IE) at a 0º printing angle exhibited a higher percentage increase of approximately 73.19%, 51.40%, and 73.78% compared to the 30º, 60º, and 90º printing angles, respectively. This decline in impact strength is attributed to the orientation of the print layer relative to the direction of impact, where perpendicular alignment at 0º offers maximum resistance, while inclined layers at higher angles facilitate crack movement and reduce resistance. 3.7 Fracture properties The variation in fracture toughness and fracture energy for 3D printed samples with printing angles is shown in Fig. 9 . As the printing angle increases from 0º to 90º, there is a decreasing trend in fracture toughness, with specimens printed at 90º (E90) exhibiting the lowest fracture toughness and fracture energy. The specimens printed at a 0º orientation (E0) exhibit the highest fracture toughness, with an approximately 35.57%, 97.73%, and 159.45% increase compared to those printed at 30º, 60º, and 90º orientations, respectively. Similarly, the fracture energy is substantially higher for specimens printed at 0º orientations (E0), showing approximately 143.83%, 84.59%, and 142.29% increases compared to specimens printed at 30º, 60º, and 90º orientations, respectively. This decline in fracture toughness can be attributed to the orientation of the print layer relative to the direction of crack propagation, where perpendicular alignment at 0º offers maximum resistance, while inclined layers at higher angles facilitate crack movement and reduce resistance. 4. Conclusions This study comprehensively analyzed the mechanical properties of NextDent dental resins processed through SLA 3D printing, focusing on tensile, fracture, flexural, and impact testing. The comprehensive analysis of mechanical and thermal properties, along with chemical characterization, provides valuable insights into the behavior of 3D-printed samples fabricated using different printing orientations (0º (vertical), 30º, 60º, and 90º (horizontal). Fracture properties demonstrate a clear correlation between printing angle and fracture toughness, with specimens printed vertically (0º) displaying superior performance compared to those printed at higher angles. Similarly, impact properties exhibit a decreasing trend with increasing printing angle, highlighting the significance of perpendicular alignment for optimal impact strength. The findings emphasize the role of printing orientation in enhancing resistance to crack movement and reducing vulnerability to impact forces. Flexural properties show significant improvements with increased printing angle, with horizontally printed specimens (90º) demonstrating the highest flexural strength and modulus. This suggests that aligning print layers with the bending load direction enhances load distribution and cohesive strength, thereby improving overall flexural performance. Tensile properties reveal a pronounced decrease in strength and modulus as the printing angle deviates from the vertical orientation. This decline is attributed to reduced interlayer adhesion and alignment with the load direction, emphasizing the critical influence of print orientation on tensile performance. The FT-IR analysis revealed the chemical composition and molecular structure of the resin, indicating the presence of hydrocarbon moieties, carbonyl groups, aromatic rings, amine functionalities, and bromine-containing compounds. DMA tests showed a storage modulus of 1575 MPa at room temperature, with a glass transition temperature (Tg) of 107°C, suggesting good damping properties. TGA analysis depicted temperature-dependent weight loss behavior, with significant weight reduction attributed to composite degradation and decomposition. These findings provide valuable insights into the resin's composition, mechanical properties, and thermal stability, crucial for optimizing its use in various applications. 5. Future Scope The study highlights the significance of meticulous parameter selection and material formulation in enhancing the mechanical and thermal attributes of 3D-printed components tailored for dental applications. Future investigations could delve into factors like printing speed, infill density, and layer height to gain a holistic understanding of their impact on material properties. Such endeavors can propel the advancement of robust and long-lasting dental prosthetics and devices, ensuring superior quality and performance in clinical settings. Declarations Funding Agency This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. 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Singh, S.K., Kumar, A., Singh, S., Kumar, A., Jain, A., 2021. Investigation of thermo-mechanical properties of surface treated SiO2/epoxy nanocomposite. Materials Today: Proceedings. 38, 2861–2865. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-4627463","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":321720731,"identity":"2880866f-132f-4f7a-8c57-edb5bad679a1","order_by":0,"name":"Himanshu Bisaria","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABFklEQVRIiWNgGAWjYBACA2YwdQDKMGCQY2NvADEsiNdizM9zAMSQwK2FAaYFKpA4c0YCiMatxZydO/FzwZ87idvZ2R9+riiwY9xw8/nVDT8KJBj427sTsGmxbObdLD2z7VnizmYeY8kzBsnMBrdzym72AB0mcebsBqwOO8y7QZq34XDihsM8DJINBsxsQC1pN3iAWgwkcnFp2fyb5w9IC/vjnw0G9TwGN8+k3fyDX8s2aR42kBYGM6AthyUkZ7Afu03Alm3WvG2HjYF+MbNsMDhuwM+Tw3ZbxkCCB6dfzp/dfBvoMNnt/Mcf32z4U13fxn782c03f2zk+Nt7sWrBBnjAccRDrHIQYH9AiupRMApGwSgY/gAAZDdmXD/GTZMAAAAASUVORK5CYII=","orcid":"","institution":"School for Advanced Research in Petrochemicals: Laboratory for Advanced Research in Polymeric Materials-Central Institute of Petrochemicals Engineering \u0026 Technology, Bhubaneswar","correspondingAuthor":true,"prefix":"","firstName":"Himanshu","middleName":"","lastName":"Bisaria","suffix":""},{"id":321720732,"identity":"dc222b26-a1ff-4b7a-a4e2-0f291ec4fe6c","order_by":1,"name":"Rahul Jibhakate","email":"","orcid":"","institution":"G H Raisoni College of Engineering","correspondingAuthor":false,"prefix":"","firstName":"Rahul","middleName":"","lastName":"Jibhakate","suffix":""},{"id":321720733,"identity":"65e004b8-f958-46b2-af12-52edf2f029df","order_by":2,"name":"Sushil Kumar Singh","email":"","orcid":"","institution":"Shambhunath Institute of Engineering and Technology","correspondingAuthor":false,"prefix":"","firstName":"Sushil","middleName":"Kumar","lastName":"Singh","suffix":""},{"id":321720734,"identity":"4a32c0a0-26f5-4f49-a398-6f251409da90","order_by":3,"name":"Samarjit Singh","email":"","orcid":"","institution":"Guru Ghasidas Vishwavidyalaya","correspondingAuthor":false,"prefix":"","firstName":"Samarjit","middleName":"","lastName":"Singh","suffix":""}],"badges":[],"createdAt":"2024-06-24 04:51:28","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4627463/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4627463/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":60406868,"identity":"14b6f9a9-030f-4c3c-873d-34ae5a08d8e4","added_by":"auto","created_at":"2024-07-16 12:13:38","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":16153,"visible":true,"origin":"","legend":"\u003cp\u003ePrinting of specimen’s at different angles\u003c/p\u003e","description":"","filename":"Onlinefloatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-4627463/v1/c5dc0ae704026483db64b696.png"},{"id":60407655,"identity":"6589d773-4e77-4732-91b7-53cb53effd2c","added_by":"auto","created_at":"2024-07-16 12:21:38","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":84572,"visible":true,"origin":"","legend":"\u003cp\u003eSLA 3D printed specimen’s (a) impact (b) tensile (c) flexural test\u003c/p\u003e","description":"","filename":"Onlinefloatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-4627463/v1/1008c3315c9024d793335e52.png"},{"id":60407654,"identity":"d2f68a69-1ee9-4053-90e4-fdebae292f51","added_by":"auto","created_at":"2024-07-16 12:21:38","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":18511,"visible":true,"origin":"","legend":"\u003cp\u003eFTIR of Nextden SG resin\u003c/p\u003e","description":"","filename":"Onlinefloatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-4627463/v1/2161ab4748883c08cbbc9fa7.png"},{"id":60406866,"identity":"99779d31-608c-4dd2-809b-9446287f8ad0","added_by":"auto","created_at":"2024-07-16 12:13:38","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":12856,"visible":true,"origin":"","legend":"\u003cp\u003eDMA curve for Nextdent SG resin\u003c/p\u003e","description":"","filename":"Onlinefloatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-4627463/v1/e09cc3980c59ad20cfcdf538.png"},{"id":60406861,"identity":"a56154dd-6987-485e-acb5-c424f99e2b6d","added_by":"auto","created_at":"2024-07-16 12:13:38","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":8540,"visible":true,"origin":"","legend":"\u003cp\u003eTGA curve for Nextdent SG resin\u003c/p\u003e","description":"","filename":"Onlinefloatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-4627463/v1/9ccf3ad6e63bac70b35390c0.png"},{"id":60406863,"identity":"6566066a-e49c-4e0b-a755-a75dbd5fdf04","added_by":"auto","created_at":"2024-07-16 12:13:38","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":55577,"visible":true,"origin":"","legend":"\u003cp\u003eEffect of printing angle on tensile properties of 3D printed samples\u003c/p\u003e","description":"","filename":"Onlinefloatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-4627463/v1/999a522b543431575eee98ab.png"},{"id":60407658,"identity":"8b8cd52d-81b5-46c7-b06e-132dc241f6e1","added_by":"auto","created_at":"2024-07-16 12:21:38","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":70208,"visible":true,"origin":"","legend":"\u003cp\u003eEffect of printing angle on flexural properties of 3D printed samples\u003c/p\u003e","description":"","filename":"Onlinefloatimage7.png","url":"https://assets-eu.researchsquare.com/files/rs-4627463/v1/af14f4878b42879293dfe719.png"},{"id":60406864,"identity":"c05d592b-0245-42fd-877c-b4f9e356e188","added_by":"auto","created_at":"2024-07-16 12:13:38","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":73755,"visible":true,"origin":"","legend":"\u003cp\u003eEffect of printing angle on impact properties of 3D printed samples\u003c/p\u003e","description":"","filename":"Onlinefloatimage8.png","url":"https://assets-eu.researchsquare.com/files/rs-4627463/v1/2c36543c56388cc85358bd30.png"},{"id":60408158,"identity":"864ea0b5-c572-4fcb-a6ec-b2bd348465bd","added_by":"auto","created_at":"2024-07-16 12:29:39","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":76277,"visible":true,"origin":"","legend":"\u003cp\u003eFracture toughness and fracture energy of samples 3D printed at different angles\u003c/p\u003e","description":"","filename":"Onlinefloatimage9.png","url":"https://assets-eu.researchsquare.com/files/rs-4627463/v1/a63e8967631fa4376611b45c.png"},{"id":95774089,"identity":"12d36c74-a9e0-4073-94c7-430ace8423b9","added_by":"auto","created_at":"2025-11-13 01:08:35","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1291933,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4627463/v1/1d7edd29-14ef-47c3-98d9-f760b55b0dc9.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Influence of Printing Orientation on Mechanical Characteristics of NextDent Biocompatible Resin in SLA 3D Printing","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eStereolithography (SLA), a form of 3D printing additive manufacturing, finds extensive use across various industries, notably in biomedical applications [1]. SLA based additive manufacturing involves vat photopolymerization technology to create solid objects by the process of photopolymerization of vat of liquid resin using laser. Vat photopolymerization is superior to other additive manufacturing (AM) technologies, for example selective laser sintering (SLS) and fused deposition modeling (FDM) due to its ability to fabricate intricate complex parts with high speed, spatial resolution and precision [2]. Presently, SLA and FDM are engaged in direct competition, primarily due to the initial high cost of resin and the increasing number of SLA providers, resulting in a decline in resin prices. As 3D printing doesn't need cutting or grinding metal, it provides a great deal of design and geometric freedom to the manufacturers to meet industrial requirements beyond the conventional fabrication methods [3]. Besides offering flexibility in shapes, additive manufacturing methods can integrate various materials in one item, enabling users to switch materials during printing for intricate combinations, resulting in customized mechanical and design attributes not achievable through traditional manufacturing methods. It has transitioned from being solely a prototyping tool to being employed in the production of consumer-ready goods [4]. Companies are increasingly drawn to 3D printed products due to their minimized energy consumption and waste generation [5]. In the realm of biomedicine, 3D printed technology has been found to be the most effective owing to the possibility of fabrication of patient specific customized products. In dentistry, the use of AM techniques has been generally accepted for sophisticated treatment planning, making orthodontic and bite splints, and making surgical drill guides. It is essential that surgical guidelines for oral implantology are made precisely [6].\u003c/p\u003e \u003cp\u003eVarious parameters have been explored to observe the impact of printing pathways on mechanical properties. Increasing layer thickness reduces printing time but deteriorates the surface finish [7, 8]. In SLA, post-curing creates inter-layer linkages resulting in a smooth surface finish without visible layer interfaces [9]. The strength of the material is also influenced by changes in the infill parameter. Many scholars have investigated how different build settings affect the mechanical properties of polymer materials using various 3D printing techniques [10]. Song et al. [11] inspected the mechanical response of unidirectional 3D-printed Polylactic acid (PLA) by conducting a series of tensile, compressive, and flexural tests. Their study revealed significant anisotropy in mechanical properties due to the printing orientation and layer bonding. Key findings included the higher strength and stiffness along the printing direction and the notable impact of layer adhesion on the material's overall mechanical performance. Wang et al. [12] focused on enhancing PLA\u0026rsquo;s impact strength in fused layer modeling (FLM) through material modifications. They experimented with various additives and processing conditions to improve the toughness of PLA. The study found that specific additives significantly increased the impact resistance of PLA without compromising its printability, demonstrating a viable method to produce more durable 3D-printed PLA parts. Cantrell et al. [13] experimentally characterized the mechanical properties of 3D-printed parts made-up of Polycarbonate and Acrylonitrile butadiene styrene (ABS). They performed compressive, tensile, and flexural tests to assess the materials' strength, stiffness, and failure modes. The study exposed that polycarbonate generally exhibited superior mechanical properties compared to ABS, and that both materials' properties were significantly affected by layer orientation and infill density. Ankouhi et al. [14] conducted mechanical characterization and failure analysis of 3D-printed ABS, focusing on the effects of printing orientation and layer thickness. Through tensile and impact testing, they found that thinner layers and optimized orientation significantly enhanced the mechanical performance and failure resistance of ABS parts. The study concluded that careful selection of printing parameters is crucial for maximizing the strength and durability of 3D-printed components. Torrado and Roberson [15] analyzed the failure and anisotropy of tensile test specimens with varying print raster patterns and geometries. Their evaluation, involving tensile testing, indicated that both specimen geometry and raster pattern significantly influence the mechanical properties and failure behavior. The study highlighted that certain print patterns and geometries can mitigate anisotropy, leading to more uniform strength and improved performance in 3D-printed parts. Durgun and Ertan [16] conducted an experimental investigation of the Fused Deposition Modeling (FDM) technique to enhance mechanical properties while considering production cost. Through systematic experimentation and analysis, they identified optimal process parameters that improved mechanical strength without significantly increasing production expenses. Their findings contribute valuable insights into optimizing FDM for cost-effective yet high-performance 3D printing applications. Sood et al. [17, 18] conducted a comprehensive investigation into the mechanical properties of FDM parts. The study involved a parametric appraisal to understand how different printing parameters affect mechanical properties. They performed experimental investigations and developed empirical models specifically aimed at enhancing compressive strength through optimized FDM processing. Lee et al. [19] measured the anisotropic compressive strength of AM parts. Through their study, they assessed how the orientation of the printed layers affects the compressive strength of the parts. Vega et al. [20] investigated the influence of layer orientation on both microstructure and mechanical properties of a polymer. Through their study, they examined how different printing orientations affect the material's mechanical performance and internal structure. This research contributes to a deeper understanding of how printing parameters impact the final properties of 3D-printed parts, providing valuable insights for optimizing printing processes and material selection. Rao et al. [21] explored the influence of conventional drilling and additive fabrication techniques on the tensile properties of 3D-printed ONYX/CGF composites. Their study investigated how different methods of creating holes within the composites affect their mechanical behavior. By comparing conventionally drilled holes to additively fabricated ones, the research provides insights into optimizing manufacturing processes for composite materials, offering potential enhancements in strength and performance. It likely includes experimental comparisons of tensile strength and modulus between specimens with these different hole fabrication methods, aiming to optimize composite performance. Compared to traditional fabrication techniques, SLA-printed surgical guides are purported to enhance the precision of implant positioning. Even with drill guides, achieving a fully predictable implant position isn't guaranteed. Surgical guidelines printed via SLA exhibited discrepancies of up to 13% from the intended design. These errors primarily stem from data manipulation by the operator or irregular fitting of the surgical guide. Notably, the latter issue may indicate inaccuracies in the fabrication process of SLA-printed surgical guides [22].The precision of SLA printing can be influenced by both the printing process itself and the characteristics of the photosensitive resins employed. While SLA printing typically involves preset parameters like printing speed, cured line width, energy distribution, and cure depth, certain preprocessing settings such as configuring supporting structures, positioning objects on the build platform, and determining object orientation must be adjusted. Additionally, operators have control over post-processing steps like washing, cleaning, and final polymerization, all of which can impact the precision and mechanical properties of the produced parts. Variations in both pre- and post-processing procedures may affect the accuracy and mechanical characteristics of the final product [23]. The stability of surgical drill guides during use is crucial to prevent fracture and bending. Studies have shown that different printing directions can influence the mechanical properties of various SLA materials. A new class I biocompatible resin designed for surgical guide production has recently been introduced and utilized in clinical settings for tasks such as implant placement and sinus grafting [24]. However, for this particular resin type, the manufacturer provides specifications for flexural properties but lacks information regarding the effects of printing process parameters on these properties.\u003c/p\u003e \u003cp\u003eFrom the literature review, it can be summarized that there is currently no existing research that explores the utilization of this specific resin in SLA manufacturing to analyze how processing settings impact accuracy and mechanical properties. Therefore, this study aims to investigate the effects of print orientation, part placement on the build platform, and post-curing processes on the mechanical properties of SLA-produced items. Tensile, flexural, fracture and impact test were conducted for mechanical analysis. Thermogravimetric Analysis (TGA) and Dynamic Mechanical Analysis (DMA) tests were conducted for analyzing the thermal stability and thermo-mechanical behavior of resin respectively. For identifying chemical compound, FT-IR test of resin was also performed. The information gathered can guide dental professionals in optimizing printing parameters and design considerations for specific dental applications, ensuring the fabrication of high-quality and durable dental prosthetics and devices.\u003c/p\u003e"},{"header":"2. Materials and Methodology","content":"\u003cp\u003eIn this study, samples intended for dental surgical guides in implant surgery were crafted using a biocompatible class I \u0026ldquo;NextDent\u0026rdquo; SG (surgical guide) resin This material is specifically engineered for high-precision dental 3D printing applications, ensuring its suitability and efficacy for implant procedures. Identified by its translucent orange color, the resin's specifications and properties, as determined from testing, are outlined in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. The samples were produced using the UltraOne, a high-resolution 4K desktop 3D printer manufactured by U3DS (Utpal 3D Systems). With support for layer heights from 0.025 mm to 0.2 mm and a spacious printing area of 120 \u0026times; 68 \u0026times; 200 mm, this printer caters to various applications, particularly those utilizing 405 nm resins. Specimen models were designed using CAD software and saved in the STL (Stereolithography) file format. These models were then imported into Chitubox software for slicing and G-code generation. To investigate the impact of printing orientation on mechanical properties, specimens were printed at four orientations: 0\u0026deg;, 30\u0026deg;, 60\u0026deg;, and 90\u0026deg; as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. Various mechanical tests, including flexural, tensile, fracture, and impact assessments, were conducted on these samples. The details of characterizations of 3D printed samples are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. The 3D-printed specimens, as depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, underwent cleaning with ethanol to remove excess resin before testing. Subsequently, to ensure optimal polymer conversion, they were cleaned, dried, and post-cured using UV radiation.\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\u003eProperties of the NextDent SG resin used for 3D printing\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\u003eProperty\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eResult\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRequirement\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eStandard\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUltimate Flexural Strength\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;50 MPa\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eISO 20795-1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGlass transition temperature (\u003cem\u003eT\u003c/em\u003e\u003csub\u003e\u003cem\u003eg\u003c/em\u003e\u003c/sub\u003e )\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e107\u0026deg;C\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eASTM 5418\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFlexural Modulus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2118\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;1500 MPa\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eISO 20795-1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBiocompatibility\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eComply\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNon-cytotoxic\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eISO 10993-1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eResidual monomer\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026le;\u0026thinsp;2.2% (w/w)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eISO 20795-1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBiocompatibility\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eComply\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNot a sensitizer\u003c/p\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eISO 10993-1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCompounds\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eC\u0026thinsp;=\u0026thinsp;O stretching vibrations\u003c/p\u003e \u003cp\u003eO-H stretching\u003c/p\u003e \u003cp\u003eC-N stretching\u003c/p\u003e \u003cp\u003eC-H stretching\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eASTM\u003c/p\u003e \u003cp\u003eE1252-98/\u003c/p\u003e \u003cp\u003eE168-06\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBiocompatibility\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eComply\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNon-mutagenic\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eISO 10993-1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStorage modulus (GPa)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.575\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eASTM 5418\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\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\u003eDetails of test performed on 3D printed samples\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTest\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eEquipment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eStandard\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSpecimen Dimensions\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eConditions\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eMeasured Parameters\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\u003eFT-IR\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePerkinElmer Spectrum 3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eASTM E1252-98/E168-06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eWavenumber range: 400 to 4000 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eChemical composition\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eDMA\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDMA Q800\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eASTM 5418\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e50 \u0026times; 13 \u0026times; 3 mm\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eBending mode frequency: 1 Hz, Temperature range: Room temp to 200\u0026deg;C Heating rate: 10\u0026deg;C/min,\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eDamping, loss modulus, storage modulus\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTGA\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTGA Q50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eASTM E 1131\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e15\u0026ndash;25 mg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTemperature range: 30\u0026deg;C to 800\u0026deg;C, N\u003csub\u003e2\u003c/sub\u003e flow: 20 mL/min, Heating rate: 10\u0026deg;C/min\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eThermal stability\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTensile\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eInstron 3382 UTM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eASTM D-638 (Type-V)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9.53 mm (total length), 7.62 mm (gauge length), 3.18 mm (width), 3.2 mm (thickness)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eStrain rate: 5 mm/min, Temperature: Ambient\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eTensile strength\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eFlexural\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eInstron 3382 UTM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eASTM D-790\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e58 mm (length), 12 mm \u0026times; 2.7 mm (cross-section)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSpan length: 45 mm, Load rate: 1.30 mm/min\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eFlexural strength, flexural modulus\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eImpact\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eIzod impact tester (Tinius Olsen)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eASTM D 256\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e63.5 \u0026times; 12.7 \u0026times; 5 mm\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eImpact strength\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eFracture\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eInstron 3382 UTM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eASTM D5045-14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e48 mm (span length), 6 mm (thickness), 12 mm (breadth), 6 mm (crack length)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCross head speed: 0.5 mm/min\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCritical energy release rate (G\u003csub\u003eIC\u003c/sub\u003e), Fracture toughness (K\u003csub\u003eIC\u003c/sub\u003e),\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"3. Results and Discussion","content":"\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e3.1 FT-IR\u003c/h2\u003e \u003cp\u003eThe FT-IR analysis of the resin unveiled several prominent absorption peaks indicative of its chemical composition and molecular structure. As depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, the FT-IR graph of the resin showcased a broad peak at 3377.47 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, suggesting the incidence of O-H stretching vibrations characteristic of alcohols or phenols. Furthermore, peaks observed at 2924.20 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, 1451.83 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, 1406. cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and 1382.54 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e linked to C-H stretching and bending vibrations in alkanes, further indicating the presence of hydrocarbon moieties within the resin. Notably, peaks at 1717.96 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 1653.71 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e signified C\u0026thinsp;=\u0026thinsp;O stretching vibrations, potentially originating from carbonyl groups present in esters or carboxylic acids. The spectrum also exhibited multiple peaks associated with C\u0026thinsp;=\u0026thinsp;C stretching vibrations in aromatic rings, including those at 1607.97 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, 1560.33 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, 1508.38 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and 1244.84 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. Moreover, characteristic vibrations of amine groups were detected, such as N-H bending at 1541.40 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and C-N stretching at 1295.67 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, 1130.22 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and 1062.27 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, suggesting the presence of aromatic and aliphatic amine functionalities. Furthermore, the presence of bromine-containing compounds was indicated by peaks around 589.22 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 574.58 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, agreeing to C-Br stretching vibrations in alkyl bromides.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e3.2 DMA\u003c/h2\u003e \u003cp\u003eDynamic Mechanical Analysis (DMA) tests were conducted at an oscillating frequency of 1Hz to explore the dynamic storage modulus (E') and loss factor (tanδ) of 3D-printed epoxy specimens [25]. Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e displays the storage modulus variation concerning temperature. At room temperature, the pure epoxy exhibited a storage modulus of 1575 MPa. An essential property of thermosetting polymers is the glass transition temperature (Tg), representing the shift from a glassy to a rubbery state. In this investigation, Tg values corresponded to peaks in the damping factor (Tan δ) curves. The ratio of E'' to E', indicating the energy dissipated as heat per cycle, defines the damping capability or the material's ability to absorb vibration energy. Typically, temperatures where Tan δ exceeds 0.3 denote good damping properties. For the 3D-printed epoxy specimens, the glass transition temperature (Tg) was identified as 107\u0026deg;C.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e3.3 TGA\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e illustrates the temperature-dependent weight loss behavior of SG resin. TGA curve divulges three different zones of weight loss as the temperature upsurges. The initial weight loss of approximately 5% is observed in resin at temperatures of 286\u0026ordm;C. The initial weight loss observed is primarily attributed to the removal of moisture content present in the composites. As the temperature further increases, a substantial weight loss of around 69.58% is observed. This significant weight reduction occurs at higher temperatures and is likely associated with the degradation and decomposition of the composite constituents. The max. weight loss rate (%/\u0026ordm;C) was 1.333 at temperature 432.19\u0026deg;C.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e3.4 Tensile properties\u003c/h2\u003e \u003cp\u003eThe tensile strength (TS) of the specimens varies significantly with the printing orientation. As depicted in the Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e, the highest tensile strength is observed in specimens printed at 0\u0026ordm; (E0 orientation). As the printing angle increases, there is a gradual decrease in tensile strength, with the lowest value recorded for specimens printed horizontally at 90\u0026ordm; (E90 orientation). Similarly, the tensile modulus (TM) shows a decreasing trend as the printing angle increases. Specimens printed at 0\u0026ordm; exhibit the highest tensile modulus, while those printed horizontally at 90\u0026ordm; demonstrate the lowest tensile modulus. The tensile strength (TS) at a 0\u0026ordm; printing angle was observed to be higher by 15.49%, 25.88%, and 43.53% respectively compared to the 30\u0026ordm;, 60\u0026ordm;, and 90\u0026ordm; printing angles. Similarly, the tensile modulus (TM) at a 0\u0026ordm; printing angle was found to be higher by 15.18%, 36.02%, and 51.42% respectively compared to the 30\u0026ordm;, 60\u0026ordm;, and 90\u0026ordm; printing angles. The reduction in tensile properties is likely due to decreased interlayer adhesion and misalignment of print layers with the load direction as the printing angle deviates from the vertical orientation. Previous research has observed a significant influence of print layer orientation on the mechanical properties of 3D-printed specimens. Horizontal printing (90\u0026ordm;) typically results in lower mechanical qualities compared to vertical printing (0\u0026ordm;), which often yields the highest tensile strength and modulus. These findings emphasize the importance of selecting the appropriate printing angle to optimize the desired mechanical performance of 3D-printed components. To fully understand the relationship between printing parameters and mechanical properties, future studies should investigate additional factors such as infill density, layer height, and printing speed.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e3.5 Flexural properties\u003c/h2\u003e \u003cp\u003eThe flexural strength increases significantly as the printing angle increases as represented in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e. The specimens printed at a 90\u0026ordm; angle (E90) exhibit the highest flexural strength followed by those printed at a 60\u0026ordm; angle (E60), 30\u0026ordm; (E30) and 0\u0026ordm; (E0). Similarly, the flexural modulus follows a similar trend of increasing with the printing angle. The flexural strength (FS) at a 0\u0026ordm; printing angle was higher by approximately 19.02%, 67.51%, and 216.26% compared to the 30\u0026ordm;, 60\u0026ordm;, and 90\u0026ordm; printing angles, respectively. Similarly, the flexural modulus (FM) at a 0\u0026ordm; printing angle exhibited a higher percentage increase of about 53.38%, 150.66%, and 206.47% compared to the 30\u0026ordm;, 60\u0026ordm;, and 90\u0026ordm; printing angles, respectively. Printing at steeper angles allows for better alignment of the printed layers with the bending load direction, resulting in improved load distribution and enhanced resistance to bending forces. Consequently, specimens printed at 90\u0026ordm; exhibit the highest flexural properties, while those printed vertically (0\u0026ordm;) display the lowest. Printing objects horizontally (90\u0026ordm;) optimizes load distribution, minimizing shear stresses and enhancing cohesive strength, while maximizing load-bearing capacity compared to vertical printing (0\u0026ordm;). Additionally, the longer span of printed layers in the cross-section further improves flexural properties through enhanced interlayer adhesion and structural integrity.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e3.6 Impact properties\u003c/h2\u003e \u003cp\u003eThe effect of printing angles on impact strength and impact energy of 3D printed samples is illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e. As the printing angle increases from 0\u0026ordm; to 90\u0026ordm;, there is a decreasing trend in impact strength and impact energy, with specimens printed at 90\u0026ordm; (E90) exhibiting the lowest impact strength. At 0\u0026ordm; printing angle, the impact strength was notably higher by approximately 11.59%, 23.73%, and 25.96% compared to the 30\u0026ordm;, 60\u0026ordm;, and 90\u0026ordm; printing angles, respectively. Similarly, the impact energy (IE) at a 0\u0026ordm; printing angle exhibited a higher percentage increase of approximately 73.19%, 51.40%, and 73.78% compared to the 30\u0026ordm;, 60\u0026ordm;, and 90\u0026ordm; printing angles, respectively. This decline in impact strength is attributed to the orientation of the print layer relative to the direction of impact, where perpendicular alignment at 0\u0026ordm; offers maximum resistance, while inclined layers at higher angles facilitate crack movement and reduce resistance.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e3.7 Fracture properties\u003c/h2\u003e \u003cp\u003eThe variation in fracture toughness and fracture energy for 3D printed samples with printing angles is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e. As the printing angle increases from 0\u0026ordm; to 90\u0026ordm;, there is a decreasing trend in fracture toughness, with specimens printed at 90\u0026ordm; (E90) exhibiting the lowest fracture toughness and fracture energy. The specimens printed at a 0\u0026ordm; orientation (E0) exhibit the highest fracture toughness, with an approximately 35.57%, 97.73%, and 159.45% increase compared to those printed at 30\u0026ordm;, 60\u0026ordm;, and 90\u0026ordm; orientations, respectively. Similarly, the fracture energy is substantially higher for specimens printed at 0\u0026ordm; orientations (E0), showing approximately 143.83%, 84.59%, and 142.29% increases compared to specimens printed at 30\u0026ordm;, 60\u0026ordm;, and 90\u0026ordm; orientations, respectively. This decline in fracture toughness can be attributed to the orientation of the print layer relative to the direction of crack propagation, where perpendicular alignment at 0\u0026ordm; offers maximum resistance, while inclined layers at higher angles facilitate crack movement and reduce resistance.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"4. Conclusions","content":"\u003cp\u003eThis study comprehensively analyzed the mechanical properties of NextDent dental resins processed through SLA 3D printing, focusing on tensile, fracture, flexural, and impact testing. The comprehensive analysis of mechanical and thermal properties, along with chemical characterization, provides valuable insights into the behavior of 3D-printed samples fabricated using different printing orientations (0\u0026ordm; (vertical), 30\u0026ordm;, 60\u0026ordm;, and 90\u0026ordm; (horizontal).\u003c/p\u003e \u003cp\u003e \u003col\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eFracture properties demonstrate a clear correlation between printing angle and fracture toughness, with specimens printed vertically (0\u0026ordm;) displaying superior performance compared to those printed at higher angles. Similarly, impact properties exhibit a decreasing trend with increasing printing angle, highlighting the significance of perpendicular alignment for optimal impact strength. The findings emphasize the role of printing orientation in enhancing resistance to crack movement and reducing vulnerability to impact forces.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eFlexural properties show significant improvements with increased printing angle, with horizontally printed specimens (90\u0026ordm;) demonstrating the highest flexural strength and modulus. This suggests that aligning print layers with the bending load direction enhances load distribution and cohesive strength, thereby improving overall flexural performance.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eTensile properties reveal a pronounced decrease in strength and modulus as the printing angle deviates from the vertical orientation. This decline is attributed to reduced interlayer adhesion and alignment with the load direction, emphasizing the critical influence of print orientation on tensile performance.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eThe FT-IR analysis revealed the chemical composition and molecular structure of the resin, indicating the presence of hydrocarbon moieties, carbonyl groups, aromatic rings, amine functionalities, and bromine-containing compounds.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eDMA tests showed a storage modulus of 1575 MPa at room temperature, with a glass transition temperature (Tg) of 107\u0026deg;C, suggesting good damping properties. TGA analysis depicted temperature-dependent weight loss behavior, with significant weight reduction attributed to composite degradation and decomposition. These findings provide valuable insights into the resin's composition, mechanical properties, and thermal stability, crucial for optimizing its use in various applications.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003c/ol\u003e \u003c/p\u003e"},{"header":"5. Future Scope","content":"\u003cp\u003eThe study highlights the significance of meticulous parameter selection and material formulation in enhancing the mechanical and thermal attributes of 3D-printed components tailored for dental applications. Future investigations could delve into factors like printing speed, infill density, and layer height to gain a holistic understanding of their impact on material properties. Such endeavors can propel the advancement of robust and long-lasting dental prosthetics and devices, ensuring superior quality and performance in clinical settings.\u003c/p\u003e"},{"header":"Declarations","content":" \u003ch2\u003eFunding Agency\u003c/b\u003e \u003c/p\u003e \u003cp\u003eThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.\u003c/p\u003e \u003ch2\u003eDeclaration of interests\u003c/h2\u003e \u003cp\u003eThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eH.Bisaria did paper writingRahul Compile the results Sushil Kumar Singh did calculations on fracture and other mechanical testingSamarjit Singh compile the conclusions and overall paper correction\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003e\u003cspan\u003eLakkala, P., Munnangi, S.R., Bandari, S., Repka, M., 2023. 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IOP Conf Series: Materials Science and Engineering. 330, 012001.\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003eSingh, S.K., Kumar, A., Singh, S., Kumar, A., Jain, A., 2021. Investigation of thermo-mechanical properties of surface treated SiO2/epoxy nanocomposite. Materials Today: Proceedings. 38, 2861\u0026ndash;2865.\u003c/span\u003e\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"NextDent resin, 3D printing, mechanical properties, printing angle, tensile testing, flexural testing, fracture testing, TGA, DMA, FT-IR","lastPublishedDoi":"10.21203/rs.3.rs-4627463/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4627463/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe use of 3D printing in dentistry has revolutionized the manufacturing of dental prosthetics and devices. This research focuses on examining the mechanical properties of NextDent dental resins when processed through 3D printing. A variety of mechanical tests, including tensile, fracture, flexural testing, and impact testing are performed on specimens printed using NextDent resins. The thermo-mechanical and thermal behavior of the resin was assessed using Dynamic Mechanical Analysis and Thermogravimetric Analysis testing respectively. The specimens are fabricated at different printing angles, including 0\u0026ordm; (vertical), 30\u0026ordm;, 60\u0026ordm;, and 90\u0026ordm; (horizontal), to assess the impact of printing orientation on the mechanical properties. The mechanical properties were found superior at 0\u0026ordm; (vertical) followed by 30\u0026ordm; 60\u0026ordm; \u0026amp; 90\u0026ordm;. Fourier-transform infrared spectroscopy (FT-IR) analysis revealed the resin's molecular composition, including C-H, C\u0026thinsp;=\u0026thinsp;C, O-H, N-H, C-N, and C\u0026thinsp;=\u0026thinsp;O stretching and bending vibrations, indicating functional groups, suggesting bromine-containing compounds. DMA test\u0026rsquo;s result showed a storage modulus of 1575 MPa at room temperature, with a glass transition temperature (Tg) of 107\u0026deg;C, suggesting good damping properties.\u003c/p\u003e","manuscriptTitle":"Influence of Printing Orientation on Mechanical Characteristics of NextDent Biocompatible Resin in SLA 3D Printing","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-07-16 12:13:32","doi":"10.21203/rs.3.rs-4627463/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"caf263b5-44d3-4ead-a3c7-d164a71815aa","owner":[],"postedDate":"July 16th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-11-13T01:08:11+00:00","versionOfRecord":[],"versionCreatedAt":"2024-07-16 12:13:32","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4627463","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4627463","identity":"rs-4627463","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}