Search Results (195)

Part segmentation of industrial 3D models is often limited by the lack of sufficiently large and consistently labeled training datasets. This study proposes a workflow for generating synthetic segmentation datasets from robust parametric computer-aided design (CAD) models and evaluates its applicability on a dental abutment case. The workflow includes the definition of a modeling strategy, creation of a robust parametric CAD model, automated generation of valid geometry variants, and preparation of labeled training data for point-cloud-based segmentation. In the experimental part of the study, a synthetic dataset of segmented dental abutment geometries was generated from the developed parametric CAD model and used to train a PointNeXt-S part-segmentation model. The segmentation performance of the trained model was evaluated on manually labeled real-world abutments. Results show that the segmentation of industrial 3D models improved with increasing synthetic training-set size and further improved when data augmentation was applied. The best-performing augmented model achieved a mean Intersection over Union (IoU) of 89.2% on the real-world validation set, compared with 82.4% without augmentation. The findings indicate that parametric-CAD-based synthetic dataset generation can provide an effective basis for training segmentation models for complex industrial geometries. Full article

The increasing adoption of digital workflows in implant dentistry relies heavily on the accuracy of implant scan bodies (ISBs), which may be affected by repeated sterilization. This in vitro study evaluated the effect of 50 steam sterilization cycles on the dimensional stability of polymer and titanium ISBs. A total of 100 test specimens (n = 50 per material) were scanned before (T0) and after sterilization (T50) using a high-resolution intraoral scanner, generating 900 STL datasets for metrological analysis. Surface deviation, linear displacement, and angular deviation were assessed using validated industrial and dental software, with statistical evaluation performed through paired tests and linear mixed-effects models. Both materials exhibited statistically significant dimensional changes after sterilization (p < 0.001). Titanium scan bodies demonstrated greater linear deformation (69.76 μm) compared to polymer ones (49.50 μm), while maintaining superior angular stability (0.21° vs. −1.69° mean angular change in the polymer group). A significant interaction between material type and sterilization was observed. Despite high baseline precision, repeated autoclaving induced clinically relevant deviations in both materials. These findings indicate that cumulative sterilization cycles adversely affect ISB accuracy and highlight the importance of adhering to manufacturer recommendations to ensure optimal prosthetic outcomes. Full article

This study proposes the development of a recycling process for the reintegration of dental zirconia waste into CAD/CAM systems for rapid prototyping, with the objective of demonstrating the feasibility of manufacturing functional products from recycled zirconia obtained from a commercial dental laboratory. The proposed methodology aims to explore a simple and economically viable process, which involves the purification and processing of a heterogeneous zirconia powder, followed by the fabrication of pre-sintered blocks suitable for CAD/CAM applications. The recycled bulk ceramic was characterized and compared with commercial zirconia through density measurements, X-ray diffraction, scanning electron microscopy, Vickers hardness, flexural strength testing, and sintering shrinkage analysis. The results indicated that, although recycled zirconia exhibits lower property values than the commercial reference material, it retains adequate characteristics for specific practical applications. Consequently, to demonstrate industrial feasibility, four components were designed using CAD and machined using CAM from the recycled blocks, simulating a rapid prototyping process. The fabricated components exhibited a smooth and flawless surface, were mechanically robust and solid to the touch, and showed well-defined contours with sharp edges. Dimensional analysis demonstrated high accuracy, with an average percentage error of 0.53% ± 0.14. These findings demonstrate that high-value ceramic waste can be reintegrated into the production chain as functional industrial components through a process that is closely aligned with the real conditions of industrial recycling, while also mitigating environmental contamination from hazardous industrial waste. Full article

Industrial and municipal wastewater may contain substances that inhibit biological processes in wastewater treatment plants (WWTPs), posing risks to operational stability and environmental protection. The aim of this study is to evaluate the practical suitability of the ISO 8192:2007 respiration inhibition test for assessing the toxicity of wastewater. Nitrified activated sludge from a municipal WWTP was used to analyze wastewater from three industrial companies, wastewater from several discharge locations at a hospital, and WWTP influent. Oxygen consumption and inhibition were determined at sample-specific dilution levels and the reference substance 3,5-dichlorophenol. Two samples from the dental department of the hospital showed toxic effects on activated sludge respiration (inhibition > 50%), while no toxic effects were observed in the remaining samples. Several samples exhibited stimulatory effects (inhibition < 0%), indicating the presence of readily biodegradable organic matter. However, inhibitory effects (0–50% inhibition) were detected in individual wastewater samples at higher concentrations. This demonstrates that the method can detect toxicological changes in wastewater and is suitable for routine monitoring and early warning in WWTPs. Full article

This article provides an overview of modern surface engineering technologies used in the manufacturing of dental components, with a particular focus on dental implants, abutments, and crowns. The main objective of the study is to critically evaluate selected surface treatment and coating deposition methods applied to materials such as titanium, zirconia, hydroxyapatite, and NiTi alloys, and to discuss their relevance in terms of functionality, biocompatibility, and sustainability. The analyzed technologies include anodic oxidation, alkaline oxidation, electrochemical coating deposition, and other surface modification approaches aimed at improving osseointegration, corrosion resistance, and antibacterial performance. This literature review was conducted as a narrative review supported by the PRISMA framework, using the Scopus and Web of Science databases for the period 2016–2025. The findings highlight the increasing importance of surface treatments as a key factor influencing the durability and clinical success of dental implant systems. At the same time, the results indicate that the environmental aspects and energy efficiency of manufacturing and surface treatment processes are still addressed only marginally or qualitatively in the available literature. The identified research gaps include the lack of quantitative data on the energy demand of individual technologies, the absence of standardized indicators for environmental impact assessment, and the limited number of comparative studies evaluating different surface modification techniques in the context of dental manufacturing. Overall, the results emphasize the need for a more systematic sustainability assessment of surface engineering as an integral part of modern dental manufacturing practice. Full article

Achieving natural esthetics has become essential for successful dental restorations and supports the use of modern non-metal materials. However, complexity in esthetic features of natural teeth, determined by both inherent color factors and hierarchical and gradient microstructures, makes recording, determination, and reproduction difficult. This often leads to misunderstanding during manufacturing and dissatisfaction with the final outcome, even when using advanced digital tools. The aim of this study was to investigate a new, easy-to-handle digital tool for determining the color of restorative materials. An industrial-level handheld color identifier, the NCS Colourpin SE, together with the corresponding NCS color system, was tested on three materials: dental resin nanocomposite, self-glazed zirconia (SGZ), and Decore zirconia pellets. The repeatability and impacts of geometrical contributions such as surface roughness and thickness on different colors were measured. The Colourpin SE offered promising repeatability. Decore zirconia showed more than 90% repeatability for most of the colors, independent of thickness. The NCS scanner showed slightly better repeatability than earlier in clinical trials with an intraoral scanner. The shades A3.5 and A3 had lower repeatability, varying from 50 to 90%. It identified effects of material thickness and surface roughness, where the thicker samples were identified with higher blackness levels, and surface roughness seemed to be coupled with a lower blackness level in color identification codes. Small but consistent differences between materials were detected, suggesting that material and manufacturing methods affect the final shade. The NCS Colourpin SE shows potential to be developed into an affordable and easy-to-handle scanner for the identification of a patient’s tooth color, enabling synchronization with digital workflows and improving the match between restoration and the patient’s natural teeth. Nevertheless, further research and development in customized applications for color identification in esthetic dentistry is still required through multidisciplinary collaboration. Full article

The paper presents the development of a correlation model for initial tensile elastic modulus for flexible polymers as a function of Shore hardness in OO and A scale based on measurement. Measured polymers are in groups of silicone rubber, nitrile butadiene rubber (NBR), thermoplastic polyurethane (TPU) and silicone. The model is composed of piecewise exponential functions with fixed coefficients chosen to minimize the S₂ error norm and absolute value of relative error at the measured data points. Every chosen section of the hardness scale has one exponential function correlating the hardness to tensile elastic modulus with the argument in the form of a polynomial up to the fourth degree. The coefficients for the polynomial arguments were determined by enforcing interpolation conditions in a chosen set of points in the logarithmic scale for the elastic modulus. The correlation model possesses C0 continuity. For each material, five specimens were used for hardness measurements and five for the elastic modulus testing. The correlation model gives a positive value for elastic modulus of 0 for hardness, and a “finite”, “reasonable” value of 100 for hardness and is monotonic. Tensile properties were evaluated using true stress and logarithmic (Hencky) strain, with iterative correction of the changing cross-sectional area to account for large strain. The maximum relative error achieved in the correlation model for the OO scale is 13.4%, while for the A scale it is 7%. The developed model provides a practical and rapid method for estimating the initial tensile elastic modulus from non-destructive hardness measurements and is particularly useful in industrial applications and in the development of material models for dental surgery simulations. Full article

Circular economy (CE) decouples value creation from virgin resource use and waste in the medical device sector, which faces stringent patient-safety, quality, and regulatory obligations. Green Additive Manufacturing (AM) offers a precise, digitally driven route to implement CE through dematerialization, on-demand localized production, topology optimization, and material circularity. In this study, a comprehensive CE framework is tailored to medical device manufacturing that integrates eco-design, material circularity, remanufacturing, and regulatory compliance across the product life cycle. Methods include an International Organization for Standardization (ISO) 14040/44-aligned life cycle assessment, process energy metering, sterilization-compatibility studies, mechanical/biocompatibility verification to relevant standards, and a techno-economic/circularity analysis with Monte Carlo uncertainty quantification. Three case studies are explored using bio-based PA11 (selective laser sintering), recycled polyethylene terephthalate glycol (fused deposition modeling), and low-volatile organic carbon biocompatible photopolymer (stereolithography): (1) a patient-specific wrist orthosis, (2) a dental surgical guide, and (3) a single-use catheter Y-connector. Results indicate 38–68% reductions in embodied greenhouse-gas emissions, 22–54% energy savings per functional unit, and up to 80% mass recapture through in-process powder/runner reuse while maintaining clinical performance and regulatory conformity. Design-for-circularity patterns (DfC) were created for DfDisassembly, DfSter, DfTraceability, DfUpgrade, and DfPowder-Loop and provide a governance architecture combining ISO 13485 QMS, ISO 10993 biological evaluation, the European Union’s Medical Device Regulation (Regulation (EU) 2017/745), and the United States Food and Drug Administration’s guidance on Additive Manufactured (3D-printed) medical devices, guidance with unique device identification for closed-loop returns. The paper concludes with an Industry 5.0 roadmap for hospital-proximate micro-factories, materials passports, and digital product passports enabling verified circular flows at scale. Full article

Acmella oleracea (L.) R. K. Jansen (Asteraceae), commonly known as the “toothache plant” or “jambu,” is a significant medicinal plant that has been traditionally used in Brazil and other tropical and subtropical regions for relieving dental pain, as an anti-inflammatory agent, and as a culinary spice. Due to its versatile utility, this plant has been extensively studied in modern medicine and pharmacy for its diverse pharmacological properties, including anesthetic, analgesic, anti-inflammatory, antioxidant, and antimicrobial activities. Analytical research on the chemical compositions responsible for these activities has led to the identification of approximately 120 secondary metabolites. These findings provide scientific validation for its traditional uses and have spurred research into the development of ingredients for functional foods and cosmetics. This review incorporates the latest research findings, focusing on biological activities and compounds that have been practically isolated or can be isolated based on quantitative experimental data, to serve as a practical reference for industrial development. Furthermore, factors influencing the content of alkylamides and phenolic compounds, two major bioactive groups, are summarized to support material development. Ultimately, this review aims to provide a clearer understanding of the plant’s utility and contribute to the development of products that enhance human health. Full article

Pulpitis is the inflammatory response of the dental pulp to microbial challenge and can range from mild to severe in nature, with severe pulpitis traditionally resulting in pulp removal and root canal treatment (RCT). In the pursuit of more conservative treatments, recent clinical practice guidelines have recommended strategies that preserve the vitality of the dental pulp, rather than RCT, when possible. This has increased the focus on improving the accuracy of pulp diagnosis, which will direct treatment and improve management outcomes. Unfortunately, current point-of-care (PoC) tools are subjective, lack discrimination and rely on the stimulation of pulpal neurons, limiting dentists’ ability to objectively identify the level of inflammation. Molecular biomarker assessment has the potential to dynamically analyse pulpitis and correlate this with inflammatory thresholds and treatment outcomes. Numerous chemokines, cytokines, proteases and growth factors exhibit altered expression during pulpitis and can be collected intraoperatively as part of routine dental treatment. Although current data indicate several markers that could be used as next-generation diagnostic chairside tools for pulpitis, there are currently no commercial kits. Considering the interest in vital pulp treatment, there is an urgent need to engage researchers, industry, dentists and other stakeholders in the development of PoC diagnostic assays for pulpitis. Full article

Electrospinning, Forcespinning^®, and melt electrowriting are becoming increasingly important fiber-based fabrication technologies for tissue engineering and drug delivery applications. Despite their scientific and industrial relevance, their patent landscape has not been systematically examined, which limits the understanding of technological dynamics and translational applications. This study addresses this gap through a patentometric analysis conducted within a Competitive Technology Intelligence framework. A total of 3557 active and granted Extended Patent Families from 2020 to 2024 were analyzed to identify temporal patterns, geographic distribution, key innovators, industrial sectors, and primary application areas. The results showed that the overall patent activity increased until 2022 before experiencing a slight decline. China dominates the landscape, accounting for approximately 62% of applications filed, largely driven by academic institutions such as Shanghai University. Leading industries include special-purpose machinery, medical and dental technology, and textiles. According to International Patent Classification codes, filament formation (D01D5/00) is prevalent, while electrospinning—specifically IPC D04H1/728—represents the most active and influential of the three technologies. These findings exhibit the technological dynamics shaping fiber-based fabrication platforms and underscore their growing relevance in pharmaceutical innovation. The identified trends position these technologies as foundational for next-generation biomaterial design, offering valuable insights for researchers, industry stakeholders, and policymakers. Full article

Agricultural and agro-industrial residues are increasingly recognized as sustainable, low-cost feedstocks for high-performance biomedical materials. This review critically examines the translational potential of polysaccharides, proteins, inorganic compounds, and phytochemical-rich extracts derived from agro-waste, highlighting their chemical features, structure–function relationships, and application-specific readiness. Polysaccharides such as nanocellulose, pectin, and chitosan emerge as the most advanced biopolymer platforms, particularly in wound healing, drug delivery, and 3D-printed scaffolds. Protein-derived materials—including collagen, gelatin, keratin, and soy protein—show strong promise in regenerative medicine, though challenges in mechanical stability and batch reproducibility remain. Inorganic phases such as hydroxyapatite and silica obtained from eggshells, rice husk ash, and marine shells demonstrate high bioactivity, with dental and bone applications approaching clinical translation. Finally, fruit-residue phytochemicals provide multifunctional antioxidant and antimicrobial enhancements to composite systems. By integrating material chemistry, processing strategies, and translational considerations, this review outlines the current state, challenges, and future perspectives for advancing agro-waste-derived biomaterials within a circular bioeconomy. Full article

Zeolites are becoming potentially important multifunctional fillers in dentistry, providing a distinctive blend of mechanical reinforcement, remineralization, and antimicrobial properties. Their crystalline aluminosilicate frameworks offer ion-exchange capacity, the controlled release of therapeutic ions (Ag⁺, Zn²⁺, Ca²⁺, Sr²⁺, Cu²⁺), and compatibility with various dental composites. Sustainable and cost-effective zeolite production has become possible due to recent developments in synthetic strategies. These include the valorization of industrial and agricultural residues that are abundant in Si and Al. The incorporation of zeolites into dental adhesives, restorative composites, glass ionomer cements, root canal sealers, prosthetic materials, and implant coatings has been shown to improve mechanical stability and remineralization potential, and enhance antibacterial protection. The unique advantage of zeolites in integrating multifunctionality within a single system is emphasized when compared with other fillers, such as hydroxyapatite nanoparticles and bioactive glass. Nevertheless, obstacles persist with respect to clinical validation, regulatory pathways, and long-term biocompatibility. This review critically assesses the structure–function relationships, synthesis strategies, and dental applications of zeolites, while also delineating future perspectives for their translation into clinically approved, sustainable dental biomaterials. Full article

The sustainable conversion of biogenic waste into high-value materials presents a promising approach for addressing environmental and industrial challenges. This work reports an advancement into antioxidant-enriched phosphate minerals derived from green conversion of biogenic calcium carbonates of crustaceans. We demonstrate the effectiveness of Raman technology in controlling conversion using phosphoric acid treatment. The effects of reaction parameters—including acid stoichiometry, granular size distribution, and thermal treatment at 700 °C and 1200 °C—were systematically evaluated. Raman spectroscopy results validated by X-ray diffraction (XRD) and SEM-EDX analyses revealed mixed-phase minerals monetite, brushite, whitlockite or hydroxylapatite, respectively. Notably, reducing particle size enhanced conversion efficiency by increasing the reactive surface area, while the use of excess phosphoric acid facilitated conversion to monocalcium phosphate and promoted the degradation of the organic matrix. Thermal treatment further altered the product composition: heating at 700 °C produced a whitlockite-rich phase, whereas treatment at 1200 °C shifted the balance toward hydroxylapatite. The synthesized calcium phosphate compounds, including hydroxylapatite, monocalcium phosphate, whitlockite, and brushite, hold significant practical utility in biomedical applications (such as bone grafts and dental implants), agriculture, and industrial processing. Moreover, we have proven that by controlling the reaction parameters the final product composition can be tailored according to the specific needs. A greener approach yields brushite, monetite, or monocalcium phosphate, while a more energy-demanding process, including heating to 1200 °C, yields a high-purity hydroxylapatite. This research offers a sustainable analytical route for producing high-purity calcium phosphate materials from wasted biomaterials, contributing to both the bioeconomy as well as scientific innovation. Full article

This study examines the chemical recycling of polymethylmethacrylate (PMMA) dental waste in semi-batch fixed-bed reactors via pyrolysis, aiming to convert this waste into the valuable monomer methyl methacrylate (MMA). First, the effect of temperature is analyzed in a laboratory-scale (30 g) semi-batch reactor at 350, 400 and 450 °C. In order to visualize the combined effect of temperature and increase in bed volume, experiments conducted at 350 °C in the laboratory (30 g) and on a pilot scale (20 kg) are compared. Experiments conducted at 475°C on technical and pilot scales are also compared to elucidate this behavior. A detailed process analysis is presented, considering different experiments conducted in a semi-batch technical-scale reactor. Experiments were conducted in a 2 L reactor at temperatures of 425 °C, 450 °C and 475 °C to understand the effects of heating rate and temperature on product yield and composition. The results show that at 425 °C, MMA was the primary liquid component, with minimal by-products, suggesting that lower temperatures enhance monomer recovery. Higher temperatures, however, increased gas yields and reduced MMA yield due to intensified thermal cracking. This study also highlights that char formation and non-condensable gases increase with the reactor scale, indicating that heat transfer limitations can influence MMA purity and yield. These findings emphasize that for effective MMA recovery, lower temperatures and controlled heating rates are optimal, especially in larger reactors where heat transfer issues are more prominent. This research study contributes to scaling up PMMA recycling processes, supporting industrial applications to achieve efficient monomer recovery from waste. Full article