Silica-based materials have been commonly studied in the field of bone tissue regeneration, due to their high bioactivity and osteogenic properties. There are two main strategies to obtain silica-based materials, a melt-quenching process using high temperatures, or a sol-gel reaction which can be carried out at mild conditions. Both techniques allow the preparation of calcium silicates and bioactive glasses, but pure silica can only be prepared through the sol-gel method. Furthermore, current clinical treatments require personalized scaffolds and these materials can be combined with the use of 3D printing techniques to obtain patient-specific scaffolds in a fast and precise fabrication process. This review focuses on the different silica-based 3D printable materials available nowadays as well as their physical, chemical and biological properties. Using high temperature, composites can be developed using Fused Deposition Modelling (FDM), while pure silica scaffolds can be prepared through Selective Laser Sintering (SLS) using silica particles. Moreover, silica particles can be 3D printed when combining polymeric binders and SLS, Stereolitography (SLA) or Direct Ink Writing (DIW); however, binder has to be removed at high temperatures after 3D printing. Alternatively, 3D printable silica materials can be obtained at mild temperatures through DIW or SLA, in this case only allowing the printing of composites or hybrids so far, with different proportions of silica. The properties of the resultant materials as well as the main advantages and disadvantages of the printing approaches are summarized in this review, together with the future perspectives in the field of silica 3D printed scaffolds.

The rising prevalence of bone diseases in an aging population underscores the urgent need for innovative and clinically translatable solutions in bone tissue engineering. While significant progress has been made in refining the chemical properties of biomaterials, the structural design of scaffolds-a critical determinant of repair success-remains comparatively underexplored. Structural parameters such as porosity, pore size, and interconnectivity are not only essential for achieving mechanical stability but also pivotal in regulating biological processes, including vascularization, osteogenesis, and immune modulation. This review systematically categorizes scaffold architectures documented in the literature and highlights how these design parameters can be optimized to enhance bone regeneration. Advanced fabrication technologies, particularly 3D printing, are emphasized for their transformative potential in creating precise, biomimetic scaffolds that align with the complex functional demands of native bone. Furthermore, this work synthesizes diverse findings to provide a comprehensive framework for designing next-generation scaffolds. By bridging the gap between structural innovation and clinical application, this review delivers actionable strategies and a strategic roadmap for advancing the field toward improved clinical outcomes and transformative breakthroughs in regenerative medicine.

Lignin is the second most abundant renewable and sustainable biomass resource. Developing advanced manufacturing to process lignin/lignocellulose into functional materials could reduce the consumption of petroleum-based materials. 3D printing provides a promising strategy to realize complex and customized geometries of lignin materials. The heterogeneity and complexity of lignin hinder its processing via additive manufacturing, but the recent advancement in lignin modification and polymerization provides new opportunities. Here, we summarize the recent state-of-the-art 3D printing of lignin materials, including the selection and formulation of lignin materials based on different printing techniques, the chemical modification of lignin for enhanced printability, and the related application fields. Additionally, we highlight the significant role of the 3D printing of lignocellulose biomass materials, such as wood powder and agricultural wastes. It was concluded that the most challenging part is to enhance the printability of lignin materials through modification and pretreatment of lignin while keeping the whole process green and sustainable. Beyond 3D printing, we further discuss the development of smart lignin materials and their potential for 4D printing. Ultimately, we discuss the current challenges and potential opportunities for the additive manufacturing of lignin materials. We believe this review can raise awareness among researchers about the potential of lignin materials as whole materials for constructing blocks and can promote the development of 3D/4D printing of lignin towards sustainability.

Three-dimensional (3D) printing is an emerging technology with the potential to increase manufacturing flexibility and enable personalized drug delivery. 3D printing may form tablets using digitally controlled layer-by-layer material deposition, permitting the tailoring of solid oral dosage geometry and facile modifications of drug release profiles without requiring extensive alterations to the pharmaceutical formulation and process. The challenge to assure the quality of drugs still lies in monitoring and controlling critical steps in the 3D printing process. Optimizing an 3D printing process requires a comprehensive understanding of the critical process parameters, material attributes and their impact on the performance of 3D-printed tablets. This review focuses on recent advances in 3D printing technologies for solid oral dosage forms, emphasizing critical process parameters and material attributes that may be considered for optimizing printing processes and enhancing the quality of printed tablets. Additionally, this review explores real-time analytical tools and the crucial considerations for ensuring the performance of building materials, printing processes, and manufactured solid drug products. This review contributes to the ongoing discourse on harnessing the potential of 3D printing in the pharmaceutical field while emphasizing the imperative need for quality assurance throughout additive manufacturing processes.

We report on enhancing the mechanical and structural characteristics of polypropylene (PP) three-dimensional (3D)-printed structures fabricated via fused filament fabrication (FFF) by employing hybrid PP-based filament containing a minute amount of polyethylene terephthalate glycol (PETG) inclusions. The improvement was obtained by increasing adhesion through rapid macromolecular interdiffusion between PETG inclusions, enriching the boundary. The inclusions serve as anchoring elements and enhance layer-to-layer adhesion via the interlocking mechanism. In our work, four different hybrid filaments containing 0.7, 1.4, 2.1%, and 3.5 vol % of PETG were produced via melt extrusion of the PP/PETG blend. The samples with 0.7-2.1% PETG had an average diameter of dispersed phase of about 1.2-1.4 μm. The size of PETG inclusions was noticeably larger for 3.5% PETG samples (∼1.9 μm). It was determined that introducing PETG into the PP matrix has practically no effect on the PP thermal transitions. Via X-ray photoelectron spectroscopy (XPS) measurements, we determined that the concentration of PETG material on the filament surface is 10-20 times higher than that in bulk. As the polyester content increases, the surface area occupied by the inclusions increases from approximately 7 to 55%. Our results show that utilization of the hybrid PP/PETG filaments significantly improves the printed parts' mechanical characteristics and sintering level compared to those made from pure PP filament. Specifically, incorporating 0.7% of PETG into the PP filament increased Young's modulus of the printed structures by 80%. Modulus increase by ∼55% was caused by adding 2.1 and 3.5% of PETG. For the yield stress, the addition of 0.7 and 2.1/3.5% of PETG led to an increase of the stress by about 50 and 30%, respectively. In general, the improvement of mechanical characteristics is higher for the lowest content of the PETG inclusions dispersed in the PP matrix. The result indicated that more efficient interfacial anchoring occurs at reduced PETG concentrations where the layer-to-layer contact is not overpopulated with the polyester domains.

Additive manufacturing, also known as 3D printing, is becoming more and more popular because of its wide range of materials and flexibility in design. Layer by layer, 3D complex structures can be generated by the revolutionary computer-aided process known as 3D bioprinting. It is particularly crucial for youngsters and elderly patients and is a useful tool for tailored pharmaceutical therapy. A lot of research has been carried out recently on the use of polysaccharides as matrices for tissue engineering and medication delivery. Still, there is a great need to create affordable, sustainable bioink materials with high-quality mechanical, viscoelastic, and thermal properties as well as biocompatibility and biodegradability. The primary biological substances (biopolymers) chosen for the bioink formulation are proteins and polysaccharides, among the several resources utilized for the creation of such structures. These naturally occurring biomaterials give macromolecular structure and mechanical qualities (biomimicry), are generally compatible with tissues and cells (biocompatibility), and are harmonious with biological digesting processes (biodegradability). However, the primary difficulty with the cell-laden printing technique (bioprinting) is the rheological characteristics of these natural-based bioinks. Polysaccharides are widely used because they are abundant and reasonably priced natural polymers. Additionally, they serve as excipients in formulations for pharmaceuticals, nutraceuticals, and cosmetics. The remarkable benefits of biological polysaccharides-biocompatibility, biodegradability, safety, non-immunogenicity, and absence of secondary pollution-make them ideal 3D printing substrates. The purpose of this publication is to examine recent developments and challenges related to the 3D printing of stimuli-responsive polysaccharides for site-specific medication administration and tissue engineering.

The growing interest in gel-based additive manufacturing, also known as three-dimensional (3D) gel-printing technology, for research underscores the crucial need to develop robust biobased materials with excellent printing quality and reproducibility. The main focus of this study is to prepare and characterize some composite gels obtained with a low-molecular-weight gelling (LMWG) peptide called Fmoc-diphenylalanine (Fmoc-FF) and two types of cellulose nanofibrils (CNFs). The so-called Fmoc-FF peptide has the ability to self-assemble into a nanowire shape and therefore create an organized network that induces the formation of a gel. Despite their ease of preparation and potential use in biological systems, unfortunately, those Fmoc-FF nanowire gel systems cannot be 3D printed due to the high stiffness of the gel. For this reason, this study focuses on composite materials made of cellulose nanofibrils and Fmoc-FF nanowires, with the main objective being that the composite gels will be suitable for 3D printing applications. Two types of cellulose nanofibrils are employed in this study: (1) unmodified pristine cellulose nanofibrils (uCNF) and (2) chemically modified cellulose nanofibrils, which ones have been grafted with polymers containing the Fmoc unit on their backbone (CNF-g-Fmoc). The obtained products were characterized through solid-state cross-polarization magic angle-spinning 1H NMR and confocal laser scanning microscopy. Within these two CNF structures, two composite gels were produced: uCNF/Fmoc-FF and CNF-g-Fmoc/Fmoc-FF. The mechanical properties and printability of the composites are assessed using rheology and challenging 3D object printing. With the addition of water, different properties of the gels were observed. In this instance, CNF-g-Fmoc/Fmoc-FF (c = 5.1%) was selected as the most suitable option within this product range. For the composite bearing uCNF, exceptional print quality and mechanical properties are achieved with the CNF/Fmoc-FF gel (c = 5.1%). The structures are characterized by using field emission scanning electron microscopy (FESEM) and small-angle X-ray scattering (SAXS) measurements.

Thre e-dimensional (3D) printing is an emerging technology that expanded quickly into a diverse array of clinical applications over the last decade. 3D printing, often called additive manufacturing, uses specialized printers to create objects through the addition of materials layer-by-layer. Using computer-aided design software via a 3D scanner or a digital camera, objects can be printed to highly precise and specific dimensions. This technology, including both the hardware and software, has applications in surgical procedures, dental implants and crowns, pharmaceuticals, and biomedical products. With the enormous potential of using 3D printing in multiple health care sectors, there is still limited usage for this technology in maternal and child health nursing practice. We provide an overview of 3D printing technology, review the current health care applications, and explore the opportunities and challenges of 3D printing in maternal and child nursing.

The development of cost-effective, flexible, and scalable microfluidic devices is crucial for advancing organ-on-a-chip (OoC) technology for drug discovery and disease modeling applications. In this study, we present a novel 3D-printed flexible microfluidic device (3D-FlexTPU-MFD) fabricated through a one-step fused deposition modeling (FDM) process using thermoplastic polyurethane (TPU) as the printing filament and polyvinyl chloride (PVC) as the bonding substrate. The device's compatibility was evaluated with various cell types, including human primary myoblasts, human primary endothelial cells (HUVEC), and human iPSC-derived optic vesicle (OV) organoids. Myoblasts cultured within the device exhibited high viability, successful differentiation, and the formation of aligned myotube bundles, outperforming conventional well-plate cultures. Additionally, iPSC-derived OV organoids-maintained viability, displayed neurite outgrowth, and sustained expression of the eye marker PAX6. These results demonstrate that the 3D-FlexTPU-MFD effectively supports cell growth, differentiation, and alignment, making it a promising platform for tissue modeling and OoC applications in future.

Surgical guides are integral tools in orthodontics, enhancing the precision and predictability of mini-implant placement. These guides facilitate accurate positioning, reduce risks to surrounding anatomical structures, and ensure proper angulation and depth during procedures. The aim of the present paper is to present a detailed review of the surgical guides used in orthodontics, focusing on their classification, mechanical properties, biocompatibility, and future developments. The advantages, disadvantages, clinical steps, and implications are also described based on the data in recent scientific literature. Future developments may incorporate artificial intelligence and augmented reality, further optimizing treatment planning and patient outcomes, thus solidifying the role of surgical guides in efficient orthodontic care.

Currently, bone tissue engineering is a research hotspot in the treatment of orthopedic diseases, and many problems in orthopedics can be solved through bone tissue engineering, which can be used to treat fractures, bone defects, arthritis, etc. More importantly, it can provide an alternative to traditional bone grafting and solve the problems of insufficient autologous bone grafting, poor histocompatibility of grafts, and insufficient induced bone regeneration. Growth factors are key factors in bone tissue engineering by promoting osteoblast proliferation and differentiation, which in turn increases the efficiency of osteogenesis and bone regeneration. 3D printing technology can provide carriers with better pore structure for growth factors to improve the stability of growth factors and precisely control their release. Studies have shown that 3D-printed scaffolds containing growth factors provide a better choice for personalized treatment, bone defect repair, and bone regeneration in orthopedics, which are important for the treatment of orthopedic diseases and have potential research value in orthopedic applications. This paper aims to summarize the research progress of 3D printed scaffolds containing growth factors in orthopedics in recent years and summarize the use of different growth factors in 3D scaffolds, including bone morphogenetic proteins, platelet-derived growth factors, transforming growth factors, vascular endothelial growth factors, etc. Optimization of material selection and the way of combining growth factors with scaffolds are also discussed.

Bone defects are due to trauma, infections, tumors, or aging, including bone fractures, bone metastases, osteoporosis, or osteoarthritis. The global burden of these demands research into innovative strategies that overcome the limitations of conventional autografts. In this sense, the development of three-dimensional (3D) bioprinting has emerged as a promising approach in the field of tissue engineering and regenerative medicine (TERM) for the on-demand generation and transplantation of tissues and organs, including bone. It combines biological materials and living cells, which are precisely positioned layer by layer. Despite obtaining some promising results, 3D bioprinting of bone tissue still faces several challenges, such as generating an effective vascular network to increase tissue viability. In this review, we aim to collect the main knowledge on methods and techniques of 3D bioprinting. Then, we will review the main biomaterials, their composition, and the rationale for their application in 3D bioprinting for the TERM of bone.

Superficial lesions of the face are often treated with an electron beam and surface collimation utilizing a conformal lead shield with an opening around the region of treatment (ROT). To fabricate the lead shield, an imprint of the patient face is needed. Historically, this was achieved using a laborious and time-consuming process that involved a gypsum imprinted model (GIM) of the patient topography. We propose utilization of 3-dimentional (3D) printing technology to create a 3-dimensional printed custom model (3D-PCM) of the patient facial topography as a more accurate and more efficient alternative to GIM. GIM and 3D-PCM were generated for three patients requiring en face electron therapy of the nose. The models for both methods were then CT-scanned and fused rigidly to the CT of the patient. The accuracy of the models was compared with the CT image of the patient via visual inspection and the Sørensen-Dice similarity coefficient (DSC). The efficiency of the two methods was evaluated by the average time needed to complete each process based on user-reported experience. The average DSC between the patient and GIM is 0.95336 (standard deviation (SD) = 0.0099479), while the average DSC of the patient and 3D-PCM is 0.97886 (SD = 0.0037441). With respect to efficiency, the average time to fabricate and dry GIM is 54.5 hours with hands-on time of 2.5 hours, while generation of 3D-PCM takes about 6.5 hours, with hands on time of approximately 2.5 hours. 3D-PCMs based on CT scan images are found to be an excellent substitute for GIMs by exhibiting a higher degree of fidelity with patient's anatomy, requiring significantly less time to complete, being less labor intensive, and allowing for greater patient comfort. The disadvantage of exposing the patient to radiation associated with the CT scan image acquisition for designing a 3D-PCM could be eliminated by employing 3D-camera scanning technology.

The advent of 3D printing technology has emerged as a key technical revolution in recent years, enabling the development and production of innovative medication delivery methods in the pharmaceutical sector. The designs, concepts, techniques, key challenges, and potential benefits during 3D-printing technology are the key points discussed in this review. This technology primarily enables rapid, safe, and low-cost development of pharmaceutical formulations during the conventional and additive manufacturing processes. This phenomenon has wide-ranging implications in current as well as future medicinal developments. Advanced technologies such as Ink-Jet printing, drop-on-demand printing, Zip dose, Electrohydrodynamic Printing (Ejet) etc., are the current focus of the drug delivery systems for enhancing patient convenience and improving medication compliance. The current and future applications of various software, such as CAD software, and regulatory aspects in 3D and 4D printing technology are discussed briefly in this article. With respect to the prospective trajectory of 3D and 4D printing, it is probable that the newly developed methods will be predominantly utilized in pharmacies and hospitals to accommodate the unique requirements of individuals or niche groups. As a result, it is imperative that these technologies continue to advance and be improved in comparison to 2D printing in order to surmount the aforementioned regulatory and technical obstacles, render them applicable to a vast array of drug delivery systems, and increase their acceptability among patients of every generation.

Three-dimensional printing (3DP) has gained popularity among scientists and researchers in every field due to its potential to drastically reduce energy costs for the production of customized products by utilizing less energy-intensive machines as well as minimizing material waste. The 3D printing technology is an additive manufacturing approach that uses material layer-by-layer fabrication to produce the digitally specified 3D model. The use of 3D printing technology in the pharmaceutical sector has the potential to revolutionize research and development by providing a quick and easy means to manufacture personalized one-off batches, each with unique dosages, distinct substances, shapes, and sizes, as well as variable release rates. This overview addresses the concept of 3D printing, its evolution, and its operation, as well as the most popular types of 3D printing processes utilized in the health care industry. It also discusses the application of these cutting-edge technologies to the pharmaceutical industry, advancements in various medical fields and medical equipment, 3D bioprinting, the most recent initiatives to combat COVID-19, regulatory frameworks, and the major challenges that this technology currently faces. In addition, we attempt to provide some futuristic approaches to 3DP applications.

Repair and regeneration of damaged tissues due to disease and accidents have become a severe challenge to tissue engineers and researchers. In recent years, biocompatible metal materials such as stainless steels, cobalt alloys, titanium alloys, tantalum alloys, nitinol, and Mg alloys have been studied for tissue engineering applications; as suitable candidates in orthopedic and dentistry implants. These materials and their alloys are used for load-bearing and physiological roles in biological applications. Due to the suitable conditions provided by a porous material, many studies have been performed on the porous implants, including Mg-based scaffolds. Mg alloy scaffolds are attractive due to some outstanding features and susceptibilities, such as providing a cell matrix for cell proliferation, migration, and regeneration, providing metabolic substances for bone tissue growth, biocompatibility, good biodegradability, elastic modulus comparable to the natural bone, etc. Accordingly, in the present study, a general classification of all the production methods of Mg-based scaffolds is provided. Strengths and weaknesses, the effect of the production approach on the final properties of scaffolds, including mechanical and biological capabilities, and the impact of alloying elements and process parameters have been reviewed, and discussed. Finally, the manufacturing methods have been compared and the upcoming challenges have been stated.

The purpose of this study was to investigate the effects of acetyl tributyl citrate (ATBC) on the mechanical properties, abrasion resistance, and cytotoxicity of a polyurethane-based 3D printing resin for mouthguard applications. The synthesized polycarbonate-based polyurethane acrylate was formulated into digital light processing printing resins with 40 wt% triethylene glycol dimethacrylate, and different percentage of ATBC were added for further characterizations. The mechanical properties and abrasion resistance, ATBC migration, and the cytotoxicity of the resins were evaluated. The addition of ATBC in polyurethane-based resins enhanced the flexibility of printed resins. ATBC of 5-10% increased the toughness of printed resins, and the elongation at break. The printed resins with ATBC show higher hardness, comparing to conventional mouthguard materials, and have flexibility at meantime. All resins with ATBC showed no cytotoxicity and extremely low plasticizer migration, suggesting that ATBC have potential in long-term applicability. This is one of the few studies that shows the potential of adding ATBC into light-cure 3D printing resins. This study indicates that adding ATBC not only can tune the mechanical properties of 3D printing resins, but it can also showed low migration and did not increase the cytotoxicity in 3D printing resins.

The field of bone tissue engineering (BTE) has witnessed a revolutionary breakthrough with the advent of three-dimensional (3D) bioprinting technology, which is considered an ideal choice for constructing scaffolds for bone regeneration. The key to realizing scaffold biofunctions is the selection and design of an appropriate bioink, and existing bioinks have significant limitations. In this study, a composite bioink based on natural polymers (gelatin and alginate) and liver decellularized extracellular matrix (LdECM) was developed and used to fabricate scaffolds for BTE using 3D bioprinting. Through in vitro studies, the concentration of LdECM incorporated into the bioink was optimized to achieve printability and stability and to improve the proliferation and osteogenic differentiation of loaded rat bone mesenchymal stem cells (rBMSCs). Furthermore, in vivo experiments were conducted using a Sprague Dawley rat model of critical-sized calvarial defects. The proposed rBMSC-laden LdECM-gelatin-alginate scaffold, bioprinted layer-by-layer, was implanted in the rat calvarial defect and the development of new bone growth was studied for four weeks. The findings showed that the proposed bioactive scaffolds facilitated angiogenesis and osteogenesis at the defect site. The findings of this study suggest that the developed rBMSC-laden LdECM-gelatin-alginate bioink has great potential for clinical translation and application in solving bone regeneration problems.

Impact loads applied to the human head can result in skull fractures or other injuries that require a craniectomy. The removed portion is replaced with biological or synthetic materials using cranioplasty surgery. Titanium has been the material of choice for cranial implants due to its superior properties and biocompatibility; however, its issues have prompted the search for substitute materials (e.g., polymers). The issues are related to the requirement for surface modification, casting, radiologic incompatibility and potential allergy risks. Recently, polymeric materials have been used in many fields as alternatives to titanium.

This research aims to conduct a finite element study to evaluate the skull reconstruction process by using PEEK and carbon fiber reinforced PEEK 30 and 60% in the production of cranial implants as alternatives to conventional titanium implants.

A three-dimensional model of a defective skull was rehabilitated with a custom-made cranial implant. The implants were stimulated using two designs (plate and mesh), and different polymeric materials (PEEK and carbon fiber reinforced PEEK 30 and 60%) as titanium substitutes, under 2000 N impact force.

The results illustrated that plate implants reduced the stresses on the skull and increased the stresses on brain tissues compared to mesh implants. Titanium, CFR-PEEK 30 & 60% implants (whether mesh or flat) were not prone to fracture, unlike mesh PEEK implants. In addition, CFR-PEEK 60% implants produced the lowest values of stress, strain, and total deformation on the skull and brain compared to titanium implants, unlike PEEK implants. By using the titanium plate implant, the peak tensile and compressive stresses on the skull were 24.99 and 25.88 MPa, respectively. These stresses decreased to 21.6 and 24.24 MPa when using CFR-PEEK 60%, increased to 26.07 and 28.99 MPa with CFR-PEEK 30%, and significantly increased to 41.68 and 87.61 MPa with PEEK. When the titanium mesh implant was used, the peak tensile and compressive stresses on the skull were 29.83 and 33.86 MPa. With CFR-PEEK 60%, these stresses decreased to 27.77 and 30.57 MPa, and with CFR-PEEK 30% and PEEK, the stresses increased to 34.04 and 38.43 MPa, and 44.65 and 125.67 MPa, respectively. For the brain, using the titanium plate implant resulted in peak tensile and compressive stresses of 14.9 and 16.6 Pa. These stresses decreased to 13.7 and 15.2 Pa with CFR-PEEK 60%, and increased to 16.3 and 18.1 Pa, and 73.5 and 80 Pa, with CFR-PEEK 30% and PEEK, respectively. With the titanium mesh implant, the peak tensile and compressive stresses were 12.3 and 13.5 Pa. Using CFR-PEEK 60%, these stresses decreased to 11.2 and 12.4 Pa on the brain, and increased with CFR-PEEK 30% and PEEK to 14.1 and 15.5 Pa, and 53.7 and 62 Pa, respectively. Additionally, the contact area between the PEEK implant (whether mesh or plate design) and the left parietal bone of the skull was expected to be damaged due to excessive strains. Importantly, all implants tested did not exceed permissible limits for tensile and compressive stresses and strains on the brain.

It was concluded that carbon fiber-reinforced PEEK implants, with 30% and 60% reinforcements, can be used as alternatives to titanium for cranial reconstruction. The addition of carbon fibers to the PEEK matrix in these percentages enhances the mechanical, chemical, and thermal properties of the implants. Additionally, these composites are characterized by their low weight, biocompatibility, lack of clinical issues, and ease of fabrication. They can also help preserve the skull, protect the brain, and are not susceptible to damage.

Overcoming the drawbacks of titanium cranial implants and increasing the effectiveness of the cranioplasty process by utilizing PEEK and carbon fiber reinforced PEEK materials in the reconstruction of the damaged portion of skull.

Recent advancements in materials synthesis and processing technology, coupled with a deeper understanding of bone nanoscale structure and biology, have provided new avenues for designing bioactive materials in bone tissue regenerative medicine. This Review focuses on the design and application of polydopamine-modified polycaprolactone scaffolds loading metal nanoparticles for bone tissue engineering. We explore their antibacterial properties and their ability to guide cell behavior. Specifically, we discuss the synthesis techniques, protein deposition, morphology variations, and interactions with the extracellular matrix of these scaffolds and biocompatibility and efficacy in promoting bone tissue regeneration in vitro and in vivo. Challenges and unmet needs are reviewed in the development of polymer- and metal-based materials for bone tissue engineering.

The Food and Drug Administration's approval of the first three-dimensional (3D) printed tablet, Spritam®, led to a burgeoning interest in using 3D printing to fabricate numerous drug delivery systems for different routes of administration. The high degree of manufacturing flexibility achieved through 3D printing facilitates the preparation of dosage forms with many actives with complex and tailored release profiles that can address individual patient needs.

This comprehensive review provides an in-depth look into the several 3D printing technologies currently utilized in pharmaceutical research. Additionally, the review delves into vaginal anatomy and physiology, 3D-printed drug delivery systems for vaginal applications, the latest research studies, and the challenges of 3D printing technology and future possibilities.

3D printing technology can produce drug-delivery devices or implants optimized for vaginal applications, including vaginal rings, intra-vaginal inserts, or biodegradable microdevices loaded with drugs, all custom-tailored to deliver specific medications with controlled release profiles. However, though the potential of 3D printing in vaginal drug delivery is promising, there are still challenges and regulatory hurdles to overcome before these technologies can be widely adopted and approved for clinical use. Extensive research and testing are necessary to ensure safety, effectiveness, and biocompatibility.

Gold nanoparticles can generate heat upon exposure to radiation due to their plasmonic properties, which depend on particle size and shape. This enables precise control over the release of active substances from polymeric pharmaceutical formulations, minimizing side effects and premature release. The technology of 3D printing, especially vat photopolymerization, is valuable for integrating nanoparticles into complex formulations.

This study aimed to incorporate gold nanospheres (AuNSs) and nanorods (AuNRs) into polymeric matrices using vat photopolymerization, allowing for controlled drug release with exposure to 532 nm and 1064 nm wavelengths.

The AuNSs (27 nm) responded to 532 nm and the NRs (60 nm length, 10 nm width) responded to 1064 nm. Niclosamide was used as the drug model. Ternary blends of Polyethylene Glycol Diacrylate 250 (PEGDA 250), Polyethylene Glycol 400 (PEG 400), and water were optimized using DesignExpert 11 software for controlled drug release upon specific wavelength exposure. Three matrices, selected based on solubility and printability, underwent rigorous characterization. Two materials achieved controlled drug release with specific wavelengths. Bilayer devices combining AuNSs and AuNRs demonstrated selective drug release based on irradiation wavelength.

A pharmaceutical device was developed, capable of controlling drug release upon irradiation, with potential applications in treatments requiring delayed administration.

Layered rocks are prevalent in the Earth's crust and are frequently encountered in underground engineering construction. Due to their pronounced anisotropy, the deformation and failure mechanism of layered rock are complex. Laboratory tests are an effective way to study these mechanisms. However, natural layered rocks present challenges, such as difficult sampling and large discreteness. Additionally, current methods for creating layered rock models are often costly or lack precision, limiting research into their mechanical properties. In this study, a 3D printing process using wet material extrusion was adopted, with a wide range of material options and low production costs. Five layered model samples with bedding dip angles of 0°, 30°, 45°, 60° and 90° were printed using this method. Uniaxial compression tests were conducted, supplemented by digital image correlation (DIC) to capture detailed stress-strain data and failure patterns. The results demonstrate that the mechanical properties of the 3D-printed samples closely resemble those of natural layered rocks and exhibit significant anisotropy. This approach presents a new cost-effective method for studying the mechanical behavior of layered rock.

In the context of the digital revolution, 3D printing technology brings innovation to the personalized treatment of cervical spondylosis, a clinically common degenerative disease that severely impacts the quality of life and increases the economic burden of patients. Although traditional surgeries, medications, and physical therapies are somewhat effective, they often fail` to meet individual needs, thus affecting treatment adherence and outcomes. 3D printing, with its customizability, precision, material diversity, and short production cycles, shows tremendous potential in the treatment of cervical spondylosis. This review discusses the multiple applications of 3D printing in the treatment of cervical spondylosis, including the design, manufacture, and advantages of 3D-printed cervical collars, the role of 3D models in clinical teaching and surgical simulation, and the application of 3D-printed scaffolds and implants in cervical surgery. It also discusses the current challenges and future directions.

Three-dimensional printing (3DP) has emerged as a game-changing technology in the pharmaceutical industry, providing novel formulation development in the pharmaceutical sector as a whole, which improved patients' individualized therapy. The pediatric population is among the key targets for individualized therapy. Children are a diverse group that includes neonates, infants, and toddlers, each with unique physiological characteristics. Treatment adherence has a significant impact on safe and effective pharmacotherapy in the pediatric population. Improvement of therapeutic dosage forms that provide for the special demands of the pediatric population is a significant challenge for the pharmaceutical industry. Scientists have actively explored 3DP, a quick prototype manufacturing method that has emerged in recent years from many occupations due to its benefits of modest operation, excellent reproducibility, and vast adaptability. This review illuminates the most widely used 3DP technology and its application in the development of pediatric-friendly drug formulations. This 3DP technology allows optimization of pediatric dosage regimens and cases that require individualized treatment, such as geriatrics, renal impairment, liver impairment, critically ill, pregnancy populations, and drugs with nonlinear pharmacokinetics. The fast evolution of 3DP expertise, in addition to the introduction of pharmaceutical inks, has enormous promise for patient dosage form customization.

Personalized orthopedic devices are increasingly favored for their potential to enhance long-term treatment success. Despite significant advancements across various disciplines, the seamless integration and full automation of personalized orthopedic treatments remain elusive. This paper identifies key interdisciplinary gaps in integrating and automating advanced technologies for personalized orthopedic treatment. It begins by outlining the standard clinical practices in orthopedic treatments and the extent of personalization achievable. The paper then explores recent innovations in artificial intelligence, biomaterials, genomic and proteomic analyses, lab-on-a-chip, medical imaging, image-based biomechanical finite element modeling, biomimicry, 3D printing and bioprinting, and implantable sensors, emphasizing their contributions to personalized treatments. Tentative strategies or solutions are proposed to address the interdisciplinary gaps by utilizing innovative technologies. The key findings highlight the need for the non-invasive quantitative assessment of bone quality, patient-specific biocompatibility, and device designs that address individual biological and mechanical conditions. This comprehensive review underscores the transformative potential of these technologies and the importance of multidisciplinary collaboration to integrate and automate them into a cohesive, intelligent system for personalized orthopedic treatments.

In recent years, four-dimensional (4D) fabrication has emerged as a powerful technology capable of revolutionizing the field of tissue engineering. This technology represents a shift in perspective from traditional tissue engineering approaches, which generally rely on static-or passive-structures (e.g., scaffolds, constructs) unable of adapting to changes in biological environments. In contrast, 4D fabrication offers the unprecedented possibility of fabricating complex designs with spatiotemporal control over structure and function in response to environment stimuli, thus mimicking biological processes. In this review, an overview of the state of the art of 4D fabrication technology for the obtainment of cellularized constructs is presented, with a focus on shape-changing soft materials. First, the approaches to obtain cellularized constructs are introduced, also describing conventional and non-conventional fabrication techniques with their relative advantages and limitations. Next, the main families of shape-changing soft materials, namely shape-memory polymers and shape-memory hydrogels are discussed and their use in 4D fabrication in the field of tissue engineering is described. Ultimately, current challenges and proposed solutions are outlined, and valuable insights into future research directions of 4D fabrication for tissue engineering are provided to disclose its full potential.

The emergence of 4D printing has become a pivotal tool to produce complex structures in biomedical applications such as tissue engineering and regenerative medicine. This chapter provides a concise overview of the current state of the field and its immense potential to better understand the involved technologies to build sophisticated 4D-printed structures. These structures have the capability to sense and respond to a diverse range of stimuli, which include changes in temperature, humidity, or electricity/magnetics. First, we describe 4D printing technologies, which include extrusion-based inkjet printing, and light-based and droplet-based methods including selective laser sintering (SLS). Several types of biomaterials for 4D printing, which can undergo structural changes in various external stimuli over time were also presented. These structures hold the promise of revolutionizing fields that require adaptable and intelligent materials. Moreover, biomedical applications of 4D-printed smart structures were highlighted, spanning a wide spectrum of intended applications from drug delivery to regenerative medicine. Finally, we address a number of challenges associated with current technologies, touching upon ethical and regulatory aspects of the technologies, along with the need for standardized protocols in both in vitro as well as in vivo testing of 4D-printed structures, which are crucial steps toward eventual clinical realization.

Acute wounds are converted to chronic wounds due to advanced age and diabetic complications. Nanozymes catalyze ROS production to kill bacteria without causing drug resistance, while microneedles (MNs) can break through the skin barrier to deliver drugs effectively. Nanozymes can be intergrateded into MNs delivery systems to improve painless drug delivery. It can also reduce the effective dose of drug sterilization while increasing delivery efficiency and effectively killing wounded bacteria while preventing drug resistance. This paper describes various types of metal nanozymes from previous studies and compares their mutual enhancement with nanozymes. The pooled results show that the MNs, through material innovation, are able to both penetrate the scab and deliver nanozymes and exert additional anti-inflammatory and bactericidal effects. The catalytic effect of some of the nanozymes can also accelerate the lysis of the MNs or create a cascade reaction against inflammation and infection. However, the issue of increased toxicity associated with skin penetration and clinical translation remains a challenge. This study reviews the latest published results and corresponding challenges associated with the use of MNs combined with nanozymes for the treatment of wounds, providing further information for future research.

Since three-dimensional (3D) bioprinting has emerged, it has continuously to evolved as a revolutionary technology in surgery, offering new paradigms for reconstructive and regenerative medical applications. This review highlights the integration of 3D printing, specifically bioprinting, across several surgical disciplines over the last five years. The methods employed encompass a review of recent literature focusing on innovations and applications of 3D-bioprinted tissues and/or organs. The findings reveal significant advances in the creation of complex, customized, multi-tissue constructs that mimic natural tissue characteristics, which are crucial for surgical interventions and patient-specific treatments. Despite the technological advances, the paper introduces and discusses several challenges that remain, such as the vascularization of bioprinted tissues, integration with the host tissue, and the long-term viability of bioprinted organs. The review concludes that while 3D bioprinting holds substantial promise for transforming surgical practices and enhancing patient outcomes, ongoing research, development, and a clear regulatory framework are essential to fully realize potential future clinical applications.

Material-extrusion-based 3D printing with polylactic acid (PLA) has transformed the production of lightweight lattice structures with a high strength-to-weight ratio for various industries. While PLA offers advantages such as eco-friendliness, affordability, and printability, its mechanical properties degrade due to environmental factors. This study investigated the impact resistance of PLA lattice structures subjected to material degradation under room temperature, humidity, and natural light exposure. Four lattice core types (auxetic, negative-to-positive (NTP) gradient in terms of Poisson's ratio, positive-to-negative (PTN) gradient in terms of Poisson's ratio, and honeycomb) were analyzed for variations in mechanical properties due to declines in yield stress and failure strain. Mechanical testing and numerical simulations at various yield stress and failure strain levels evaluated the degradation effect, using undegraded material as a reference. The results showed that structures with a negative Poisson's ratio exhibited superior resistance to local crushing despite material weakening. Reducing the material's brittleness (failure strain) had a greater impact on impact response compared to reducing its yield stress. This study also revealed the potential of gradient cores, which exhibited a balance between strength (maintaining similar peak force to auxetic cores around 800 N) and energy absorption (up to 40% higher than auxetic cores) under moderate degradation (yield strength and failure strain at 60% and 80% of reference values). These findings suggest that gradient structures with varying Poisson's ratios employing auxetic designs are valuable choices for AM parts requiring both strength and resilience in variable environmental conditions.

The aim of this study is to provide an overview of the current state-of-the-art in the fabrication of bioceramic scaffolds for bone tissue engineering, with an emphasis on the use of three-dimensional (3D) technologies coupled with generative design principles. The field of modern medicine has witnessed remarkable advancements and continuous innovation in recent decades, driven by a relentless desire to improve patient outcomes and quality of life. Central to this progress is the field of tissue engineering, which holds immense promise for regenerative medicine applications. Scaffolds are integral to tissue engineering and serve as 3D frameworks that support cell attachment, proliferation, and differentiation. A wide array of materials has been explored for the fabrication of scaffolds, including bioceramics (i.e., hydroxyapatite, beta-tricalcium phosphate, bioglasses) and bioceramic-polymer composites, each offering unique properties and functionalities tailored to specific applications. Several fabrication methods, such as thermal-induced phase separation, electrospinning, freeze-drying, gas foaming, particle leaching/solvent casting, fused deposition modeling, 3D printing, stereolithography and selective laser sintering, will be introduced and thoroughly analyzed and discussed from the point of view of their unique characteristics, which have proven invaluable for obtaining bioceramic scaffolds. Moreover, by highlighting the important role of generative design in scaffold optimization, this review seeks to pave the way for the development of innovative strategies and personalized solutions to address significant gaps in the current literature, mainly related to complex bone defects in bone tissue engineering.

The synchronized development of mineralized bone and blood vessels is a fundamental requirement for successful bone tissue regeneration. Adequate energy production forms the cornerstone supporting new bone formation. ETS variant 2 (ETV2) has been identified as a transcription factor that promotes energy metabolism reprogramming and facilitates the coordination between osteogenesis and angiogenesis. In vitro molecular experiments have demonstrated that ETV2 enhances osteogenic differentiation of dental pulp stem cells (DPSCs) by regulating the ETV2- prolyl hydroxylase 2 (PHD2)- hypoxia-inducible factor-1α (HIF-1α)- vascular endothelial growth factor A (VEGFA) axis. Notably, ETV2 achieves the rapid reprogramming of energy metabolism by simultaneously accelerating mitochondrial aerobic respiration and glycolysis, thus fulfilling the energy requirements essential to expedite osteogenic differentiation. Furthermore, decreased α-ketoglutarate release from ETV2-modified DPSCs contributes to microcirculation reconstruction. Additionally, we engineered hydroxyapatite/chitosan microspheres (HA/CS MS) with biomimetic nanostructures to facilitate multiple ETV2-DPSC functions and further enhanced the osteogenic differentiation. Animal experiments have validated the synergistic effect of ETV2-modified DPSCs and HA/CS MS in promoting the critical-size bone defect regeneration. In summary, this study offers a novel treatment approach for vascularized bone tissue regeneration that relies on energy metabolism activation and the maintenance of a stable local hypoxia signaling state.

The three-dimensional (3D) printing technology has led to transformative shift in prosthodontics. This review summarizes the evolution, processing techniques, materials, integration of digital plan, challenges, clinical applications and future directions of 3D printing in prosthodontics. It appraises from the launch of 3D printing to its current applications in prosthodontics. The convergence of printing technology with digital dentistry has facilitated the creation of accurate, customized prostheses, redefining treatment planning, design, and manufacturing processes. The progression of this technology is from generating models to prosthesis like-fixed dental prosthesis (FDP), implants, and splints. Additionally, it exhibits more wide capabilities. The exploration of materials for 3D printing provides various options like polymers, ceramics, metals, and hybrids, each with distinctive properties that are applicable to different clinical scenarios. The combination of 3D-printing technology and digital workflow simplifies the processes of data transfer, computer-aided design (CAD) design to fabrication, decreasing errors and chairside time. The clinical benefits include enhanced accuracy, comfort, conservative lab procedures, and economics. Challenges in the technology involve significant aspects like initial investment, material availability, and skill requirements. Future trends emphasize on research for improved materials, bioprinting integration, artificial intelligence (AI) application, regularization efforts to ensure safe and common use of the technology. 3D printing offers promise in prosthodontics, addressing challenges through research. The material improvements will promote its broader adoption and revolutionize the future of dental rehabilitation.

This study assessed AI-processed low-dose cone-beam computed tomography (CBCT) images for single-tooth diagnosis. Human-equivalent phantoms were used to evaluate CBCT image quality with a focus on the right mandibular first molar. Two CBCT machines were used for evaluation. The first CBCT machine was used for the experimental group, in which images were acquired using four protocols and enhanced with AI processing to improve quality. The other machine was used for the control group, where images were taken in one protocol without AI processing. The dose-area product (DAP) was measured for each protocol. Subjective clinical image quality was assessed twice by five dentists, with a 2-month interval in between, using 11 parameters and a six-point rating scale. Agreement and statistical significance were assessed with Fleiss' kappa coefficient and intra-class correlation coefficient. The AI-processed protocols exhibited lower DAP/field of view values than non-processed protocols, while demonstrating subjective clinical evaluation results comparable to those of non-processed protocols. The Fleiss' kappa coefficient value revealed statistical significance and substantial agreement. The intra-class correlation coefficient showed statistical significance and almost perfect agreement. These findings highlight the importance of minimizing radiation exposure while maintaining diagnostic quality as the usage of CBCT increases in single-tooth diagnosis.

This study outlined the prevalent use of brachytherapy in skin cancers, such as basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). The importance of customized applicator fabrication for optimal treatment delivery was highlighted, focusing on adaptable devices tailored to individual patient anatomy, often facilitated by 3D printing technology. The purpose of this work was to investigate the association of medical science and 3D printing in customized applicator fabrication for brachytherapy, leveraging the advancements in fabrication techniques to enhance treatment precision and patient outcomes.

The study enrolled five patients with tumor lesions unsuitable for surgical intervention, situated across various anatomical locations, such as earlobe, temple, hand, and cheek. Customized applicators were fabricated via 3D printing (fused deposition modeling) for each patient, followed by radiotherapy protocol delivering a total dose of 51 Gy in 17 fractions. Patient assessments during and post-radiotherapy were done by radiation oncologist using RTOG scale as well as dermatological evaluations with dermatoscopy and reflectance confocal microscopy. Methodologically, applicators were 3D-printed using fused deposition modeling technology. Printing parameters were optimized in Prusa Slicer software, ensuring precise control in printout shape correlated with treatment efficacy.

This study examined the therapeutic outcomes of brachytherapy in five patients with inoperable skin cancer lesions. Utilizing customized 3D-printed applicators, the patients underwent brachytherapy regimen delivering a cumulative dose of 51 Gy in 17 fractions. The evaluation with RTOG scale revealed varied treatment responses, with complete remission achieved in all cases. Reflectance confocal microscopy showed post-treatment normalization of epidermal morphology and notable scar formation. Optical profilometry demonstrated consistent micro-structures on the applicator surfaces, without compromising treatment efficacy. These findings indicated the potential of 3D-printed applicators in optimizing brachytherapy outcomes in skin cancer management.

Our study demonstrates the effectiveness of 3D-printed applicators in treating inoperable skin cancer lesions with high precision. In personalized fabrication, optimal conformity with anatomical features was achieved, resulting in complete remission in all patients. This approach minimizes treatment-related side effects and enhances overall patient outcomes, suggesting a promising future for 3D printing technology in skin cancer treatment applications. Further research and clinical validation are needed to establish 3D printing as a standard practice in skin cancer treatment.

Near-field direct-writing electrospinning technology can be used to produce ordered micro/nanofiber membrane dressings. The application of this technology can simply realize the control of dressing porosity, compound different functional substances, and adjust their distribution, thus improving the defects of common dressings such as insufficient breathability, poor moisture retention performance, and single function. Herein, a novel multifunctional wound dressing was prepared to utilize near-field direct-writing electrospinning technology, in which calf skin collagen type I (CSC-I) and polycaprolactone (PCL) were used as the composite matrix, Hexafluoroisopropanol (HFIP) as the solvent, and erythromycin (ERY) as an anti-infective drug component. The results show that the micro/nanofiber membranes prepared by near-field direct-writing electrospinning technology can all present a complete mesh structure, excellent thermal stability, and good moisturizing properties. Moreover, the composite fiber membrane loaded with ERY not only had obvious antibacterial properties against E. coli and S. thermophilus but also a better slow-release function of drugs (it is rare to have both in traditional wound dressings). Therefore, this experimental design can provide relevant theories and an experimental foundation for preparing a new type of medical dressing with drug loading and has good guiding significance for the application and promotion of near-field direct-writing electrospinning in medical dressings.

The concept of ecology, historically rooted in the economy of nature, currently needs to evolve to encompass the intricate web of interactions among humans and various organisms in the environment, which are influenced by anthropogenic forces. In this review, the definition of ecology has been adapted to address the dynamic interplay of energy, resources, and information shaping both natural and artificial ecosystems. Previously, 3D (and 4D) printing technologies have been presented as potential tools within this ecological framework, promising a new economy for nature. However, despite the considerable scientific discourse surrounding both ecology and 3D printing, there remains a significant gap in research exploring the interplay between these directions. Therefore, a holistic review of incorporating ecological principles into 3D printing practices is presented, emphasizing environmental sustainability, resource efficiency, and innovation. Furthermore, the 'unecological' aspects of 3D printing, disadvantages related to legal aspects, intellectual property, and legislation, as well as societal impacts, are underlined. These presented ideas collectively suggest a roadmap for future research and practice. This review calls for a more comprehensive understanding of the multifaceted impacts of 3D printing and the development of responsible practices aligned with ecological goals.

The present work aimed to prepare novel bio-based composites by adding fillers coming from agro-wastes to an acrylate epoxidized soybean oil (AESO) resin, using liquid crystal display (LCD) 3D printing. Different photocurable formulations were prepared by varying the reactive diluents, iso-bornyl methacrylate (IBOMA) and tetrahydrofurfuryl acrylate (THFA). Then, two fillers derived from different industrial wastes, corn (GTF) and wine (WPL-CF) by-products, were added to the AESO-based formulations to develop polymer composites with improved properties. The printability by LCD of the photocurable formulations was widely studied. Bio-based objects with different geometries were realized, showing printing accuracy, layer adhesion, and accurate details. The thermo-mechanical and mechanical properties of the 3D-printed composites were tested by TGA, DMA, and tensile tests. The results revealed that the agro-wastes' addition led to a remarkable increase in the elastic modulus, tensile strength, and glass transition temperature in the glassy state for the systems containing IBOMA and for flexible structures in the rubbery region for systems containing THFA. AESO-based polymers demonstrated tunable properties, varying from rigid to flexible, in the presence of different diluents and biofillers. This finding paves the way for the use of this kind of composite in applications, such as biomedical for the realization of prostheses.

3D printable biopolymer nanocomposites composed of hydroxyapatite nanoparticles and functionalized plant-based monomers demonstrate potential as sustainable and structural biomaterials. To increase this potential, their printability and performance must be improved. For extrusion-based 3D printing, such as Direct Ink Writing (DIW), printability is important for print fidelity. In this work, triglycerol diacrylate (TGDA) was added to an acrylated epoxidized soybean oil:polyethylene glycol diacrylate resin to increase hydrogen bonding. Greater hydrogen bonding was hypothesized to improve printability by increasing the ink's shear yield strength, and therefore shape holding after deposition. The effects of this additive on material and mechanical properties were quantified. Increased hydrogen bonding due to TGDA content increased the ink's shear yield stress and viscosity by 916% and 27.6%, respectively. This resulted in improved printability, with best performance at 3 vol% TGDA. This composition achieved an ultimate tensile strength (UTS) of 32.4 ± 2.1 MPa and elastic modulus of 1.15 ± 0.21 GPa. These were increased from the 0 vol% TGDA composite, which had an UTS of 24.8 ± 1.8 MPa and a modulus of 0.88 ± 0.06 GPa. This study demonstrates the development of bio-based additive manufacturing feedstocks for potential uses in sustainable manufacturing, rapid prototyping, and biomaterial applications.

With the advent of personalized medicine, the drug delivery system will be changed significantly. The development of personalized medicine needs the support of many technologies, among which three-dimensional printing (3DP) technology is a novel formulation-preparing process that creates 3D objects by depositing printing materials layer-by-layer based on the computer-aided design method. Compared with traditional pharmaceutical processes, 3DP produces complex drug combinations, personalized dosage, and flexible shape and structure of dosage forms (DFs) on demand. In the future, personalized 3DP drugs may supplement and even replace their traditional counterpart. We systematically introduce the applications of 3DP technologies in the pharmaceutical industry and summarize the virtues and shortcomings of each technique. The release behaviors and control mechanisms of the pharmaceutical DFs with desired structures are also analyzed. Finally, the benefits, challenges, and prospects of 3DP technology to the pharmaceutical industry are discussed.

Periodontitis, a prevalent oral condition, is facing difficulties in therapeutic approaches, sometimes leading to failure. This literature review was conducted to investigate the diversity of other therapeutic approaches and their potential contributions to the successful management of the disease. This research scrutinized the alterations in microbial diversity and imbalances in crucial microbial species, which contribute significantly to the pathogenesis of periodontitis. Within the limitations of this study, we highlight the importance of understanding the treatment plan's role in periodontitis disease, opening the way for further research and innovative treatment plans to mitigate the impact of periodontitis on oral health. This will aid both healthcare professionals and patients in preventing and effectively treating periodontitis, ultimately improving oral health outcomes and overall systemic health and well-being.

With the global population expected to reach 9.7 billion by 2050, there is an urgent need for advanced materials that can address existing and developing environmental issues. Many current synthesis processes are environmentally unfriendly and often lack control over size, shape, and phase of resulting materials. Based on knowledge from biological synthesis and assembly processes, as well as their resulting functions (e.g., photosynthesis, self-healing, anti-fouling, etc.), researchers are now beginning to leverage these biological blueprints to advance bio-inspired pathways for functional materials for water treatment, air purification and sensing. The result has been the development of novel materials that demonstrate enhanced performance and address sustainability. Here, an overview of the progress and potential of bio-inspired methods toward functional materials for environmental applications is provided. The challenges and opportunities for this rapidly expanding field and aim to provide a valuable resource for researchers and engineers interested in developing sustainable and efficient processes and technologies is discussed.

In the realm of modern medicine, tissue engineering and regeneration stands as a beacon of hope, offering the promise of restoring form and function to damaged or diseased organs and tissues. Central to this revolutionary field are biological macromolecules-nature's own blueprints for regeneration. The growing interest in bio-derived macromolecules and their composites is driven by their environmentally friendly qualities, renewable nature, minimal carbon footprint, and widespread availability in our ecosystem. Capitalizing on these unique attributes, specific composites can be tailored and enhanced for potential utilization in the realm of tissue engineering (TE). This review predominantly concentrates on the present research trends involving TE scaffolds constructed from polysaccharides, proteins and glycosaminoglycans. It provides an overview of the prerequisites, production methods, and TE applications associated with a range of biological macromolecules. Furthermore, it tackles the challenges and opportunities arising from the adoption of these biomaterials in the field of TE. This review also presents a novel perspective on the development of functional biomaterials with broad applicability across various biomedical applications.

3D bioprinting is a disruptive, computer-aided, and additive manufacturing technology that allows the obtention, layer-by-layer, of 3D complex structures. This technology is believed to offer tremendous opportunities in several fields including biomedical, pharmaceutical, and food industries. Several bioprinting processes and bio-ink materials have emerged recently. However, there is still a pressing need to develop low-cost sustainable bio-ink materials with superior qualities (excellent mechanical, viscoelastic and thermal properties, biocompatibility, and biodegradability). Marine-derived biomaterials, including polysaccharides and proteins, represent a viable and renewable source for bio-ink formulations. Therefore, the focus of this review centers around the use of marine-derived biomaterials in the formulations of bio-ink. It starts with a general overview of 3D bioprinting processes followed by a description of the most commonly used marine-derived biomaterials for 3D bioprinting, with a special attention paid to chitosan, glycosaminoglycans, alginate, carrageenan, collagen, and gelatin. The challenges facing the application of marine-derived biomaterials in 3D bioprinting within the biomedical and pharmaceutical fields along with future directions are also discussed.

To date, organ transplantation remains an effective method for treating end-stage diseases of various organs. In recent years, despite the continuous development of organ transplantation technology, a variety of problems restricting its progress have emerged one after another, and the shortage of donors is at the top of the list. Bioprinting is a very useful tool that has huge application potential in many fields of life science and biotechnology, among which its use in medicine occupies a large area. With the development of bioprinting, advances in medicine have focused on printing cells and tissues for tissue regeneration and reconstruction of viable human organs, such as the heart, kidneys, and bones. In recent years, with the development of organ transplantation, three-dimensional (3D) bioprinting has played an increasingly important role in this field, giving rise to many unsolved problems, including a shortage of organ donors. This review respectively introduces the development of 3D bioprinting as well as its working principles and main applications in the medical field, especially in the applications, and advancements and challenges of 3D bioprinting in organ transplantation. With the continuous update and progress of printing technology and its deeper integration with the medical field, many obstacles will have new solutions, including tissue repair and regeneration, organ reconstruction, etc., especially in the field of organ transplantation. 3D printing technology will provide a better solution to the problem of donor shortage.