Search Results (86)

Additive manufacturing (AM) has emerged as a key enabling technology in contemporary dental manufacturing, driven by its capacity for customization, geometric complexity, and seamless integration with digital design workflows. This article presents a technology-oriented narrative review of additive manufacturing in dental implant production, focusing on dominant processing routes, material systems, and emerging research trends rather than a systematic or critical appraisal of the literature. An indicative descriptive analysis of publications indexed in the Web of Science and Scopus databases between 2014 and 2024 was used to contextualize the technological development of the field and identify major research directions. Emphasis was placed on metal powder bed fusion technologies, specifically Selective Laser Melting (SLM) and Direct Metal Laser Sintering (DMLS), which enable the fabrication of titanium implants with controlled porosity and enhanced osseointegration. Ceramic AM approaches, including SLA, DLP, and PBF, are discussed in relation to their potential for aesthetic dental restorations and customized prosthetic components. The publication trend overview indicates a growing interest in ceramic AM after 2020, an increasing focus on hybrid and functionally graded materials, and persistent challenges related to standardization and the availability of long-term clinical evidence. Key technological limitations—including manufacturing accuracy, material stability, validated metrology, and process reproducibility—are highlighted alongside emerging directions such as artificial intelligence-assisted workflows, nanostructured surface modifications, and concepts enabling accelerated or immediate clinical use of additively manufactured dental restorations. Full article

Additive and coating technologies, such as high-velocity oxy-fuel (HVOF) thermal spraying and direct metal laser sintering (DMLS), often require extensive post-processing to meet dimensional and surface quality requirements, which remains challenging for nickel-based superalloys such as Inconel 718. This study presents the design and topology optimisation of a cutting tool with a linear cutting edge, capable of operating in turn-milling or turning modes, offering a viable alternative to conventional grinding. A non-optimised tool served as a baseline for comparison with a topology-optimised variant improving cutting-force distribution and stiffness-to-mass ratio. Finite element analyses and experimental turn-milling trials were performed on DMLS and HVOF Inconel 718 using carbide and CBN inserts. The optimised tool achieved significantly reduced roughness values: for DMLS, Ra decreased from 0.514 ± 0.069 µm to 0.351 ± 0.047 µm, and for HVOF from 0.606 ± 0.069 µm to 0.407 ± 0.069 µm. Rz was similarly improved, decreasing from 4.234 ± 0.343 µm to 3.340 ± 0.439 µm (DMLS) and from 5.349 ± 0.552 µm to 4.521 ± 0.650 µm (HVOF). The lowest measured Ra, 0.146 ± 0.030 µm, was obtained using CBN inserts at the highest tested cutting speed. All improvements were statistically significant (p < 0.005). No measurable tool wear was observed due to the small engagement and the use of a fresh cutting edge for each pass. The resulting surface quality was comparable to grinding and clearly superior to conventional turning. These findings demonstrate that combining topology optimisation with a linear-edge tool provides a practical and efficient finishing approach for additively manufactured and thermally sprayed Inconel 718 components. Full article

This study investigates the influence of plasma electrolytic oxidation (PEO) on corrosion resistance of Ti6Al4V alloys produced by direct metal laser sintering (DMLS) for orthopedic implants. PEO (300 s) and flash-PEO (60 s) coatings containing Si, Ca, P, Mg and Zn were applied on both DMLS and wrought Ti6Al4V alloys. Samples, coated and uncoated, were characterized for microstructure, morphology and composition. Electrochemical behaviour was assessed by potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) in simulated body fluid (SBF) at 37 °C. Ion release was quantified by inductively coupled plasma optical emission spectroscopy (ICP-OES). DMLS alloy was more passive than wrought Ti6Al4V, releasing ~60% less Ti and ~25% less Al, but ~900% more V. For both alloys, correlation of corrosion current and ion release indicated that 98–99% of oxidized Ti remained in the passive layer. Flash-PEO produced uniform porous coatings composed of anatase and rutile with ~50% amorphous phase, while PEO yielded heterogeneous layers due to soft sparking. In both cases, coatings were the main source of ions. For the DMLS alloy, the best protection was afforded by flash-PEO, releasing 0.01 μg cm⁻² d⁻¹ Ti, 26 μg cm⁻² d⁻¹ Al, and 0.25 μg cm⁻² d⁻¹ V over 30 days. Full article

The reconstruction of segmental bone defects requires patient-specific scaffolds that combine mechanical safety, biological functionality, and rapid manufacturing. We converted CT-derived mandibular geometry into a functionally graded Ti-6Al-4V lattice and optimised porosity, screw layout, and strut thickness through a cyber-physical loop that joins high-fidelity FEM, millisecond ANN, and a BN for uncertainty quantification. Fifteen candidate scaffolds were fabricated by direct metal laser sintering and hot isostatic pressing and were mechanically tested. FEM predicted stress and stiffness with 98% accuracy; the ANN reproduced these outputs with 94% fidelity while evaluating 10,000 designs in real time, and the BN limited failure probability to <3% under worst-case loads. The selected 55–65% porosity design reduced titanium use by 15%, shortened development time by 25% and raised multi-objective optimisation efficiency by 20% relative to a solid-plate baseline, while resisting a 600 N bite with a peak von Mises stress of 225 MPa and micromotion < 150 µm. Integrating physics-based simulation, AI speed, and probabilistic rigour yields a validated, additively manufactured scaffold that meets surgical timelines and biomechanical requirements, offering a transferable blueprint for functional scaffolds in bone and joint surgery. Full article

Background/Objectives: Guided bone regeneration one of the most widely used techniques, relies on combining bone graft material with barrier membranes or meshes. The choice of the mesh material depends on the specific clinical situation. Among the available options, titanium membranes are recognized as one of the most effective in dental implantology. The latter can be categorized into two groups: commercial and individualized. Advancements in additive manufacturing make customized titanium meshes an attractive option for bone regeneration. Customized titanium meshes can be manufactured using three main methods: selective laser sintering (SLS), selective laser melting (SLM), and direct metal laser sintering (DMLS). This review aims to provide information about the differences between the production process and the clinical outcomes. Methods: This systematic review was conducted by the Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Scoping Reviews (PRISMA-ScR). Relevant articles were sought out in the Web of Science, PubMed, and Scopus databases. Results: A total of ten articles were included and thoroughly reviewed. The type of bone graft used, the manufacturing technique, the amount of bone gain, the healing time, and the intraoperative and postoperative complications are discussed. Conclusions: All the relevant studies demonstrated good and predictable results using augmentation with individualized titanium meshes manufactured via SLS, SLM, or DMLS methods. Full article

This article presents the results of the tribological performance of 20MnCr5 (1.7147) tool steel countersamples produced by Direct Metal Laser Sintering (DMLS), as a potential material for inserts or working layers of sheet metal forming tools. Tribological tests were performed using a roller-block tribotester. The samples were sheet metals made of materials with significantly different properties: Inconel 625, titanium-stabilised stainless steel 321, EN AW-6061 T0 aluminium alloy, and pure copper. The samples and countersamples were analysed in terms of their wear resistance, coefficient of friction (COF), changes in friction force during testing, and surface morphology after tribological contact under dry friction conditions. The tests were performed on DMLSed countersamples in the as-received state. The largest gain of countersample mass was observed for the 20MnCr5/EN AW-6061 T0 friction pair. The sample mass loss in this combination was also the largest, amounting to 19.96% of the initial mass. On the other hand, in the 20MnCr5/Inconel 625 friction pair, no significant changes in the mass of materials were recorded. For the Inconel 625 sample, a mass loss of 0.04% was observed. The basic wear mechanism of the samples was identified as abrasive wear. The highest friction forces were observed in the 20MnCr5/Cu friction pair (COF = 0.913) and 20MnCr5/EN AW-6061 T0 friction pair (COF = 1.234). The other two samples (Inconel 625, 321 steel) showed a very stable value of the friction force during the roller-block test resulting in a COF between 0.194 and 0.213. Based on the changes in friction force, COFs, and mass changes in friction pair components during wear tests, it can be concluded that potential tools in the form of inserts or working layers manufactured using 3D printing technology, the DMLS method, without additional surface treatment can be successfully used for forming sheets of 321 steel and Inconel 625. Full article

This narrative review explores the role of additive manufacturing (AM) technologies in the production of dental implants, focusing on materials and key AM methods. The study discusses several materials used in implant fabrication, including porous titanium, trabecular tantalum, zirconium dioxide, polymers, and composite materials. These materials are evaluated for their mechanical properties, biocompatibility, and suitability for AM processes. Additionally, the review examines the main AM technologies used in dental implant production, such as selective laser melting (SLM), electron beam melting (EBM), stereolithography (SLA), selective laser sintering (SLS), and direct metal laser sintering (DMLS). These technologies are compared based on their accuracy, material limitations, customization potential, and applicability in dental practice. The final section presents a data source analysis of the Web of Science and Scopus databases, based on keyword searches. The analysis evaluates the research trends using three criteria: publication category, document type, and year of publication. This provides an insight into the evolution and current trends in the field of additive manufacturing for dental implants. The findings highlight the growing importance of AM technologies in producing customized and efficient dental implants. Full article

Background and Objectives: Bone regeneration (BR) is a cornerstone technique in reconstructive dental surgery, traditionally using either barrier membranes, titanium meshes, or perforated non-resorbable membranes to facilitate bone regeneration. Recent advancements in 3D technology, including CAD/CAM and additive manufacturing, have enabled the development of customized scaffolds tailored to patient needs, potentially overcoming the limitations of conventional methods. Materials and Methods: A scoping review was conducted according to the PRISMA guidelines. Electronic searches were performed in MEDLINE (PubMed), the Cochrane Library, Scopus, and Web of Science up to January 2025 to identify studies on digital technologies applied to bone augmentation. Eligible studies encompassed randomized controlled trials, cohort studies, case series, and case reports, all published in English. Data regarding digital workflows, software, materials, printing techniques, and sterilization methods were extracted from 23 studies published between 2015 and 2024. Results: The review highlights a diverse range of digital workflows, beginning with CBCT-based DICOM to STL conversion using software such as Mimics and Btk-3D^®. Customized titanium meshes and other meshes like Poly Ether-Ether Ketone (PEEK) meshes were produced via techniques including direct metal laser sintering (DMLS), selective laser melting (SLM), and five-axis milling. Although titanium remained the predominant material, studies reported variations in mesh design, thickness, and sterilization protocols. The findings underscore that digital customization enhances surgical precision and efficiency in BR, with several studies demonstrating improved bone gain and reduced operative time compared to conventional approaches. Conclusions: This scoping review confirms that 3D techniques represent a promising advancement in BR. Customized digital workflows provide superior accuracy and support for BR procedures, yet variability in protocols and limited high-quality trials underscore the need for further clinical research to standardize techniques and validate long-term outcomes. Full article

The aim of the study was to assess the mechanical and material properties of porous titanium capsules, produced by 3D printing via the DMLS (Direct Metal Laser Sintering) technique based on their potential application as carriers for anticancer drugs. The study used capsules made from the Ti-6Al-4V alloy, and analyzes the impact of geometric parameters, structural features, and printing angles (0°, 45°, and 90°) on their compressive strength. A total of 36 capsules were tested, 18 of type KTD and 18 of type KTM, each in two loading directions. The surface roughness and damage characteristics resulting from mechanical loading have also been evaluated. Statistical analysis of the results was performed using Student’s t-test. The results show that the capsules printed at an angle of 45° are characterized by the highest compressive strength, while their resistance significantly exceeds the values typical of human bone tissue. Additionally, the observed damage does not lead to the formation of sharp edges or loose fragments, which confirms the safety of their use in the body. The high surface roughness promotes tissue integration and limits capsule migration after implantation. The analyses confirm the potential of 3D-printed titanium capsules as effective and safe drug carriers in personalized anticancer therapy. Full article

Ti6Al4V titanium alloy is one of the most studied for its properties after additive manufacturing. Due to its widely use in medical applications, its properties are investigated in various aspects of surface layer property improvement and later compared to conventionally manufactured Ti-6Al-4V. In this study, the corrosion behavior in a 0.9% NaCl solution of shot peened Ti-6Al-4V prepared using direct metal laser sintering (DMLS) was examined using corrosion electrochemical testing and compared with conventionally forged titanium alloy. Shot peening was performed on previously polished samples and subsequently treated with the CrNi steel shots. Two sets of peening pressure were selected: 0.3 and 0.4 MPa. X-ray diffraction analysis (XRD), X-ray micro-computed tomography (Micro-CT), scanning electron microscope (SEM) tests with roughness and hardness measurements were used to characterize the samples. The conventional samples were characterized by an α + β structure, while the additive samples had an α’ + β martensitic structure. The obtained results indicate that the corrosion resistance of the conventionally forged Ti-6Al-4V alloy was higher than DMLSed Ti-6Al-4V alloy. The lowest corrosion rates were noted for untreated surfaces of CM/ref and DMLS/ref samples and reached 0.041 and 0.070 µA/cm², respectively. Moreover, the development of the surface has an influence on corrosion behavior. Therefore, increasing pressure results in inferior corrosion resistance. However, better performance for shot peened samples was reported in the low frequency range. This is due to the refinement of the grain acquired after the peening process. All the results obtained, related to the corrosion behavior, were satisfactory enough that the all samples can be characterized as materials suitable for implant applications. Full article

In this paper, the characterization of the deformation behavior of additively manufactured 3D-printed Ti-6Al-4V alloys during elastic and plastic deformation was carried out on the test samples deformation zone during cold deformation at room temperature. The additive manufacturing process direct metal laser sintering (DMLS) was used to 3D print the Ti-6Al-4V test samples. The temperature, i.e., stress, changes, strain, and strain rate distribution in the deformation zone of the 3D-printed Ti-6Al-4V alloy during elastic and plastic deformation were compared using static tensile tests, thermography, and digital image correlation (DIC) simultaneously. Periodic oscillations of the maximum temperature changes during elastic and plastic deformation were observed in the deformation zone. The thermoelastic effect with the lowest temperature drop between −0.47 °C and −0.54 °C was observed in the deformation zone of the 3D-printed Ti-6Al-4V testing samples during elastic deformation. A significant difference between strain and strain rate localization in the deformation zone was found immediately before fracture of the test sample. Maximum strain amounts in the range of 0.078–0.080 and strain rates of 0.025–0.027 s⁻¹ were determined. Static tensile tests, thermography, and digital image correlation were proved to be valid methods for determining the localization of stress, strain, and strain rate in the deformation zone of 3D-printed Ti-6Al-4V test samples. Full article

This article provides a comparative analysis of the dimensional accuracy and post-surface characteristics of gears produced by the 3D printing technique Direct Metal Laser Sintering (DMLS) from 1.2709 steel immediately after printing and after grinding and grinding treatment. The following tests were performed on the fabricated samples: metallography, hardness measurement, self-stress, surface roughness, and the gears’ shape were dimensioned and measured. The results show that post-processing influences the distribution of residual stress and the printed model’s hardness. The results show that heat treatment results in clear directionality marks and micropores, increasing the material’s hardness to 54.3 HRC ± 0.6 HRC, indicating effective strengthening. Grinding significantly improved the holes’ accuracy, changed the compressive intrinsic stresses to a tensile state, and reduced radial runout, improving gear geometries. In addition, it was noted that different results were obtained for roughness parameters depending on the gear tooth tested. Full article

This publication presents the results of research on selected quality features of sample models made using 3D printing technology from the Powder Bed Fusion (PBF) group and a material based on aluminum powder. Two quality areas were analyzed: tensile strength and geometric surface structure. Strength tests of thin-walled models were carried out for samples with four given thicknesses of 1, 1.4, 1.8, and 2 mm and four printing directions, namely, three in the XZ plane and one in the XY plane. The measurement of the geometric structure was carried out using optical measuring devices and by taking into account the assessment of roughness and waviness parameters. Using scanning electron microscopy (SEM), an analysis of the fracture of samples after rupture was carried out and the surface was assessed for technological defects created in the manufacturing process. The test results showed that for thin-walled sample models, there are certain technological limitations regarding the minimum sample thickness in the manufacturing process and that the strength of thin-walled models in relation to “solid” samples depends on both the sample thickness and the printing direction. Roughness parameters that determine functional quality characteristics such as friction and wear were determined and also showed a dependence on the printing direction. Full article

Metal powders for additive manufacturing are expensive, and producing new ones from mined metals has a negative ecological impact. In this work, recycled and reused metal powders from MS1 steel for direct metal laser sintering (DMLS) 3D printing were evaluated in the laboratory. The powders were recycled by melting followed by gas atomizing. Virgin, recycled, and reused metal powders were evaluated using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), metallography analysis, microhardness measurements, particle size distribution (PSD), shape factor by digital image processing (DIP), and flowability testing. The results showed that the particle distribution was modified after recycling. Kurtosis analysis revealed a reduction from −0.64 for virgin powders to −1.29 for recycled powders. The results demonstrated a positive skewness, indicating that the recycled powder contained a greater proportion of smaller particles. The shape factor was also modified and changed from 1.57 for virgin powders to 1.28 for recycled powders. The microstructure also changed, and austenite was found in the recycled powders. The microhardness of recycled powder decreased by 39% compared to the virgin powder. Recycled powders did not flow, using two different funnels to evaluate their flowability. The flowability of used powder was reduced from 4.3 s to 2.9 s. Full article

This narrative review aimed to evaluate the effectiveness of computer-aided design (CAD), computer-aided manufacturing (CAM) milled, and direct metal laser sintering (DMLS) titanium frameworks in hybrid denture prostheses. A structured PICO analysis and a review of ten publications were used to compare titanium frameworks for hybrid dentures made through milling, DMLS, and CAD-CAM milling. Prosthesis success, bone loss, patient satisfaction, framework fit, and biofilm adhesion were among the outcome indicators. The inclusion criteria included comparisons between DMLS and milled titanium frameworks, investigations of hybrid dentures with metal frameworks, and various study designs. The exclusion criteria included reviews, case reports, non-comparative research, and studies unrelated to hybrid dentures. A comprehensive search was performed up to December 2023 across PubMed, PubMed Central, Cochrane Library, Scopus, and Google Scholar, using terms such as CAD-CAM, dental implantation, dental prosthesis, bone loss, damaged maxilla/mandible, implant framework, and bone volume. Ten studies were available for the final analysis. These studies shed light on milled titanium framework’s relative effectiveness and characteristics versus DMLS for implant-supported hybrid dentures. This narrative analysis clarifies the critical roles of the CAD-CAM and DMLS frameworks in implant-supported hybrid dentures. Despite the significant benefits of both of these technologies, it is evident that more investigation is required to identify the optimal framework option for specific clinical scenarios, highlighting the importance of continuing research in this field. Full article