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Ultrasonic inspection of anisotropic materials presents challenges due to directionally dependent wave propagation and beam distortion. Specifically, conventional spherically focused probes, which aim to converge the beam to a small cross section within the solid and increase inspection resolution, can yield spatially and temporally varying focal profiles in anisotropic media. This variability can make interpreting signals from defects within the samples more difficult. To address this challenge, acoustic holograms were designed to enhance ultrasonic beam focusing in silicon wafers. Lens geometries were inversely calculated using ray tracing in pursuit of conical focusing in the solid. Analytical modeling using the angular spectrum approach predicted higher amplitude and more circular focal cross sections for the custom lenses compared to the spherical lenses. The custom lenses, along with conventional spherical lens designs, were fabricated using stereolithographic 3D printing and tested on [3 1 1] and [1 3 5] silicon wafers with etched flat bottom holes. Experimental validation showed the custom lenses produced higher contrast defect signatures with smaller cross-sectional areas from sub-wavelength defects, suggesting improved defect sensitivity and anisotropy-dependent scattering. The results showcase the potential of customized acoustic holograms to enhance ultrasonic inspection of anisotropic materials. The presented design and modeling methods provide the framework for further optimization of acoustic lenses tailored to anisotropic media. [ABSTRACT FROM AUTHOR]

This review focuses on the progressive role of 3D printing in dentistry, particularly emphasizing the use of zirconia-based and lithium disilicate (LS2)-based ceramic materials. Celebrated for their biocompatibility and esthetic resemblance to natural teeth, these materials have shown promising results with high success rates. Digital light processing (DLP) and stereolithography (SLA) have been noted for producing superior 3D-printed ceramic products. Despite facing challenges such as surface defects, mechanical strength limitations, and esthetic inconsistencies, active research is dedicated to refining the quality and esthetics of 3D-printed zirconia-based and LS2-based ceramics. This review acknowledges the need to mitigate the steep costs of this manufacturing form and recognizes the current shortfall in clinician and technician awareness of these advanced techniques. Addressing these issues through focused research on improving surface quality, dimensional accuracy, and mechanical properties of 3D-printed dental prostheses is crucial, as is enhancing the dental community's understanding and acceptance of this innovative technology. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the color alterations, flexural strength, and microhardness properties of two different 3D-printed permanent crown resins. Materials and Methods: Samples were produced from two different 3D-printed permanent crown resins: Group 1 (Saremco Crowntec, Saremco Dental) and Group 2 (P-crown V2, Senertek). Color changes (ΔE values), flexural strength, and Vickers hardness number (VHN) of the samples were calculated. Data were analyzed with Shapiro-Wilk normality test, independent t test, and Mann-Whitney U tests. The significance level was accepted as P < .05. Results: ΔE values for red wine were found to be significantly higher in Group 1 (6.43 ± 2.26; P < .001). The flexural strength values (MPa) of Group 1 were significantly higher than Group 2 in all three solutions (P < .001). There was no significant difference between the VHN values of the samples kept in wine and coffee solutions (P = .271; .827). Conclusions: 3D-printing resins are affected at different levels by coloring solutions. Microhardness and flexural strength of 3D-printed samples kept in different coloring agents are different. In the use of 3D-printing resins, product selection should be made by taking into account the individual factors such as the eating and drinking habits of the patient and the physical properties expected from the sample. [ABSTRACT FROM AUTHOR]

As a new method of acoustic focusing, metasurfaces have the advantage of achieving high-resolution focusing with compact and planar geometry in a relatively broad frequency band. Among these, the Helmholtz resonator cavity based metasurface has been widely utilized due to its superior performance. However, the research on this metamaterial has focused on the audible frequency band and it remains a challenge to apply this structure to the ultrasonic frequency band for biomedical applications. One reason is that the ultrasonic metasurfaces typically require complex and deep subwavelength microstructures, which is a great challenge to the current state-of-the-art fabrication techniques, and the other reason is that transferring metasurfaces with the conventional metal structure in air to those in water induces a significant transverse wave effect. In this study, we first designed a Helmholtz resonant cavity based metasurface working at 1.5 MHz according to the generalized Snell law, which is the frequency employed in biomedical applications. The resonant cavity unit was made of resin and air, which suppressed the transverse wave effect greatly. The makings and sparse distribution of the unit enabled the easy fabrication of the metasurface by 3D printing. Then, the focusing characteristics were investigated through numerical simulation and good focusing results were achieved, although the unit structure did not meet full phase coverage. Finally, the metasurface was fabricated, and the focusing was demonstrated experimentally. This work paves a way for the application of Helmholtz resonant cavity based metasurfaces in the biomedical ultrasound field. [ABSTRACT FROM AUTHOR]

The article extends J. S. McMullen's 2024 entrepreneurial growth model inspired by the novel and the film "The Martian", arguing that incorporating AI and 3D printing into a closed-system environment allows for continuous, rather than just survival-driven, growth. It proposes that labor substitution, independent knowledge generation, and structural capital transformation can drive exponential growth, unlike McMullen’s entropy-limited model. By focusing on human desires for comfort and long-term innovation cycles, the model envisions sustained wealth creation even in constrained environments.

The following technique describes the virtual planning of a single implant by combining an intraoral digital scan, an open-source computer-aided design software program, bone sounding, and 2D radiographic imaging. The surgical implant guide is fabricated using additive manufacturing technologies. Further, the surgical implant guide positioned in the patient's mouth is used to radiographically verify the estimated mesiodistal implant angulation before proceeding with the surgical intervention and can be modified if necessary. When a CBCT scan is not available, this technique eases implant planning procedures and minimizes possible surgical complications. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the efficacy of using a customized xenograft shell with a 1:1 mixture of particulate xenograft and autogenous bone for the reconstruction of horizontally deficient anterior maxillary alveolar ridges. Materials and Methods: CBCT images of the atrophic maxilla of eight patients were acquired and generated into 3D models. The data were transferred to a 3D printer for fabrication. During the surgery, xenograft blocks were manually sliced and customized on the 3D-printed models into bone shells. Then they were fixed to the atrophic site, and the gap was augmented with a 1:1 mixture of particulate xenograft and autogenous bone. Results: Clinical assessment showed no adverse effects; however, one patient exhibited wound dehiscence. The mean difference between the preoperative and 6-month postoperative CBCTs showed a net average bone gain of 4.06 mm at 2 mm from the crest and 4.34 mm at 5 mm from the crest, which was statistically significant. On the other hand, a statistically significant graft resorption of 1.41 mm at 2 mm from the crest and 2.19 mm at 5 mm from the crest was found when the mean difference between the immediate and 6-month postoperative CBCTs was calculated. Conclusions: Within the limitations of the study, the use of xenograft shells as a barrier for maxillary alveolar ridge reconstruction is a predictable technique; however, further investigations regarding the required time for graft consolidation are required. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the dimensional accuracy of implant impressions obtained using five different tray types and two techniques. Materials and Methods: A partially dentate maxillary Kennedy Class II model was created as a reference model through 3D printing. Then, implant analogs 4.3 mm in diameter were placed at the first premolar, first molar, and second molar sites. Five types of trays were used to create impressions: (1) metal stock trays, (2) plastic stock trays, (3) custom trays fabricated using liquid crystal display (LCD), (4) custom trays fabricated using fused deposition modeling (FDM), and (5) custom trays fabricated using urethane dimethacrylate (UDMA) resin. Open and closed tray techniques were also compared. In total, 150 impressions were obtained. The reference model and impressions were scanned using a laboratory scanner. Additionally, the positional and angular deviations of implants with different tray types and techniques were evaluated using the superimposition method. Results: There was no statistically significant difference (P > .05) between the impression accuracy with the different tray types and impression techniques. The angular deviations with plastic and UDMA trays were greater than those with metal, FDM, and LCD trays. Angular deviation at the second molar was greater when using closed plastic trays compared to open plastic trays. The highest and lowest positional deviations were observed at the first molar implant with an open plastic tray impression (mean ± SD of 62.46 ± 28.54 mm) and a closed LCD tray impression (36.59 ± 29.93 mm). The greatest angular deviation was observed with an open FDM tray impression at the first premolar implant (0.067 ± 0.024 degree), and the lowest angular deviation was observed with a closed metal stock tray impression at the second molar implant (0.039 ± 0.025 degree). Statistical differences were detected using the Mann-Whitney U test for paired groups and the Kruskal-Wallis test for groups with more than three comparisons (P > .05). Conclusions: Plastic and metal stock trays or conventional and 3D-printed custom trays can be used to obtain implant impressions for maxillary partially edentulous arches with similar dimensional accuracy. The five tray types and two techniques may be safely used to obtain impressions of partially edentulous maxillary arches with three implants. [ABSTRACT FROM AUTHOR]

3D printing techniques allow for the precise placement of living cells, biological substances, and biochemical components, establishing themselves as a promising approach in bioengineering. Recently, 3D printing has been applied to develop human-relevant in vitro cancer models with highly controlled complexity and as a potential method for drug screening and disease modeling. Compared to 2D culture, 3D-printed in vitro cancer models more closely replicate the in vivo microenvironment. Additionally, they offer a reduction in the complexity and ethical issues associated with using in vivo animal models. This focused review discusses the relevance of 3D printing technologies and the applied cells and materials used in cutting-edge in vitro cancer models and microfluidic device systems. Future prospective solutions were discussed to establish 3D-printed in vitro models as reliable tools for drug screening and understanding cancer disease mechanisms. [ABSTRACT FROM AUTHOR]

This clinical case outlines a comprehensive digital workflow for a minimally invasive multidisciplinary treatment. The process utilizes one open-source software for digital wax-up and one low-cost software to address esthetic concerns related to teeth misalignment. The patient's function was stabilized with a digitally made occlusal splint. The application of the described digital workflow technique, incorporating open-source, lowcost, and closed software, played a pivotal role in attaining a straightforward and predictable outcome with minimally invasive treatment. Furthermore, the continual evolution of technology contributes to the growing precision of dental procedures. The presented digital workflow helped formulate a predictable treatment plan, replicate a diagnostic digital wax-up, and achieve precise teeth alignment. This approach satisfactorily addressed the patient's esthetic concerns, providing an outstanding approximation of the definitive result. [ABSTRACT FROM AUTHOR]

Tooth autotransplantation is an effective treatment to replace missing teeth. Digital planning can facilitate successful autotransplantation. Guiding templates are highly recommended when performing cases in healed ridges in the posterior area to reduce excessive bone loss and increase the chances of fitting the donor tooth in the new socket. This case report highlights the use of 3D planning tools and fully guided drilling templates for successful tooth autotransplantation in the posterior area. Two tooth autotransplantations were performed in a 51-year-old patient using mandibular third molars to replace hopeless mandibular first and second molars. Root canal treatments were carried out before the surgeries, and different alveoloplasty techniques were used in each recipient area. The prosthetic phase was carried out after 9 months. Both teeth were asymptomatic, functional, and exhibited no signs of resorption or apical radiolucency and showed complete regeneration of the periodontal apparatus at the 2-year follow-up. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the usefulness of ridge augmentation using a customized titanium mesh (CTM) that was preformed by trimming and bending the commercial titanium mesh on a virtually reconstructed 3D acrylic resin model using clinical, radiologic, histologic, and histomorphometric analyses. Materials and Methods: This study was designed prospectively for patients who required vertical ridge augmentation using a staged approach before implant surgery. After installation of the CTM, grafting was performed using deproteinized porcine bone mineral covered with an absorbable membrane. Computed tomography was performed preoperatively and 6 months after simultaneous/staged guided bone regeneration to measure planned, reconstructed, and lacking bone volume, and the reconstruction rate was calculated based on these values. Clinical complications were also recorded, particularly the mesh exposure rate. At re-entry, the bone core was obtained using a trephine bur, and histologic and histomorphometric analyses were performed. Results: A total of 10 sites in eight patients were used for the study analysis. The mean planned bone volume was 1.15 cm3 (range: 0.78 to 1.56 cm3), mean lacking bone volume was 0.13 cm3 (range: 0 to 0.59 cm3), and mean reconstructed bone volume was 1.02 cm3 (range: 0.56 to 1.43 cm3). The exposure rate was 30% (3 out of 10 sites). The reconstruction rate was over 80%, except for one case that showed suppuration. From histomorphometric analysis, 27.52% ± 16.87% of new bone, 7.62% ± 5.19% of residual graft, and 64.86% ± 23.76% of connective tissue were observed. The core biopsy samples demonstrated different pseudoperiosteum layer appearances based on the healing stage of the augmented sites. In the premature bone, the inner osteogenic layer consisted of multiple layers of osteoblast cells with adjacent large blood vessels. However, in the mature augmented site, there was no specific inner osteogenic layer, and the outer fibrous layer was dominant. Conclusions: The fabrication of CTM based on the application of the 3D-printing technique makes vertical ridge augmentation easier and can reduce complications and achieve target bone acquisition. In addition, it is expected that quantitative analysis of the pseudoperiosteum layer will be facilitated using the CTM. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the precision and efficiency of a novel guide system for single implant placement in the mandibular symphyses and to evaluate whether the outcome is affected by the level of operator experience. Materials and Methods: A total of 90 implants were placed in three different mandibular cast types (Cawood and Howell class III, IV, and V). For each model, a complete denture was 3D printed. A polyether ether ketone rail with a guide sleeve was embedded in the middle of the denture. To determine the ideal implant position, the sleeve could be moved in a buccolingual direction. Adjustment of implant angulation was possible, and an angle correction of 0, 12, or 24 degrees was available. A total of 30 clinicians were divided into three groups: group 1 (experienced, n = 10), group 2 (beginner, n = 10), and group 3 (inexperienced, n = 10). Each clinician was asked to plan and perform a guided flapless implant placement in the mandibular symphysis. Two preoperative CBCT scans were taken; the first was to verify the planning, and the second was to adjust the planning if needed. Finally, a postoperative CBCT scan was taken to compare the planning to the final implant position. Results: Based on the first CBCT, the clinicians adjusted their planning by an average of 1.66 ± 1.65 mm coronally, 2.41 ± 2.44 mm apically, and by a mean angular correction of 6.08 ± 0.77 degrees. After implant placement, the mean deviation from the planned implant position was 0.87 ± 0.58 mm at the coronal aspect and 0.98 ± 0.64 mm at the apical aspect. The mean angular deviation was 6.05 ± 0.71 degrees. Overall, there were no significant differences in coronal and apical deviation (P > .05) based on the level of experience. In terms of angulation, a significant difference was found in both planning (P = .049) and placement (P = .038) between beginners and experienced clinicians. Conclusions: Guided implant placement of a single implant in the mandibular symphysis using a removable denture with guide sleeve had an acceptable level of accuracy. Clinicians with limited experience spent more time on the procedure, resulting in less angular deviation during implant planning and placement compared to experienced clinicians. [ABSTRACT FROM AUTHOR]

For photosensitive polyurethane systems, reactive diluents are indispensable components whose main role is to reduce the viscosity of the polyurethane prepolymer to meet the requirements of the photocurable 3D printing technology for high fluidity of the precursor solution. Generally, the reactive diluent would be involved in the photocuring reaction, which in turn has a remarkable impact on the mechanical, reaction kinetics, and thermodynamic characteristics of the photosensitive polyurethane system. However, this feature is usually neglected in the study of photosensitive urethane acrylate (PUA) systems, so there is a considerable necessity to investigate the mechanism of active diluents in the photocured reaction of PUA systems. In this work, the effects of α-methyl groups along the chains of diluent molecules on the photoreaction kinetics, photocurable 3D printing, mechanical and mechanical properties, and thermodynamic characteristics of PUAs were investigated employing hydroxyethyl methacrylate and hydroxyethyl acrylate as active diluents, respectively. The relationship between chemical structure and kinetics of PUA systems was also elucidated by using dynamic mechanical analysis tests. The results demonstrated that the α-methyl group blocks the migration of reactive radicals, reduces the efficiency of the photoreaction, and causes an increase in the rigidity and strength of the molecular chain. This study not only revealed the effect of α-methyl on the kinetic mechanical and thermal performance of PUA systems but also paves the way for the development of a new class of photosensitive PUA materials used for the photocurable 3D printing technology. [ABSTRACT FROM AUTHOR]

To promote an academic library makerspace, the University of Mississippi Libraries hosted a "3D selfie" booth which used body scanning technology. This booth, advertised on campus and set up outside the library during the first weeks of class, was designed to attract attention and perform outreach through the use of body scans to be printed in the makerspace at a later date. Although the hoped-for printing of "selfies" did not materialize, the project resulted in data about interested patrons and ideas for similar projects going forward. This paper serves as a case study for other academic library makerspaces interested in similar outreach. [ABSTRACT FROM AUTHOR]

It is not currently possible to directly and noninvasively measure in vivo patellofemoral joint contact force during dynamic movement; therefore, indirect methods are required. Simple models may be inaccurate because patellofemoral contact forces vary for the same knee flexion angle, and the patellofemoral joint has substantial out-of-plane motion. More sophisticated models use 3-dimensional kinematics and kinetics coupled to a subject-specific anatomical model to predict contact forces; however, these models are time consuming and expensive. We applied a principal component analysis prediction and regression method to predict patellofemoral joint contact forces derived from a robust musculoskeletal model using exclusively optical motion capture kinematics (external approach), and with both patellofemoral and optical motion capture kinematics (internal approach). We tested this on a heterogeneous population of asymptomatic subjects (n = 8) during ground-level walking (n = 12). We developed equations that successfully capture subject-specific gait characteristics with the internal approach outperforming the external. These approaches were compared with a knee-flexion based model in literature (Brechter model). Both outperformed the Brechter model in interquartile range, limits of agreement, and the coefficient of determination. The equations generated by these approaches are less computationally demanding than a musculoskeletal model and may act as an effective tool in future rapid gait analysis and biofeedback applications. [ABSTRACT FROM AUTHOR]

Due to the poor flowability of ZrO 2 particles in photopolymerization slurries, preparing high solid loading ZrO 2 ceramic slurries is particularly challenging. Improving the thixotropy of slurries have been innovatively employed to reduce the viscosity of ZrO 2 slurries. The study primarily investigates the effects of ZrO 2 particle size and solid loading on the rheological properties of photopolymerization slurries. Results indicate that the interaction forces between ZrO 2 particles and the internal structure of the slurry are key factors affecting the rheological properties. The viscosity of ZrO 2 slurries decreases with increasing ceramic particle size. Using binary size ZrO 2 particles significantly improves the rheological properties of the slurry. Additionally, it was observed that an increase in the solid loading of the slurry resulted in not only an elevated viscosity but also a reduction in the photosensitive properties of the slurry. Ultimately, a ZrO 2 ceramic slurry with high thixotropy and lower viscosity was successfully prepared at a mass ratio of coarse to fine ZrO 2 particles of 65 %:35 % and a solid loading of 80 wt%. [ABSTRACT FROM AUTHOR]

With the increasing emphasis on biocompatibility and aesthetic considerations, all-ceramic dental restorations have gradually supplanted traditional metal-ceramic restorations. Among commonly used all-ceramic dentures, glass-ceramic (GC) dentures offer excellent aesthetics but have limited load-bearing capacity, while zirconia dentures exhibit outstanding mechanical properties but lack aesthetics and cause excessive wear on opposing teeth. Additionally, GC-zirconia bilayer dentures are prone to interface fractures, which compromise their long-term durability. Therefore, this study proposes a design and preparation method for a GC/zirconia stabilized with 5 mol% yttria (5Y-PSZ) composites functionally gradient ceramic denture. The objective of this study was to enhance the similarity between dentures and natural teeth, ensuring high strength while minimizing wear on the opposing dentition. First, the influence of PSZ content on the microstructure, mechanical and tribological properties of the GC/PSZ composites was investigated by incorporating 5Y-PSZ particles (0-15 wt%) into self-prepared fluorapatite GCs. Secondly, based on the performance of the composites and the actual requirements of dentures, a gradient ceramic was designed with an increasing PSZ content from top to bottom. Finally, gradient ceramic specimens were fabricated using vat photopolymerization 3D printing technology, and their mechanical properties were thoroughly evaluated. The results indicated that the gradient ceramic material effectively combines superior strength and fracture toughness with aesthetic appeal, while also can minimize wear on the antagonistic natural teeth. This study presents a novel strategy for designing and manufacturing high-performance all-ceramic dentures. [ABSTRACT FROM AUTHOR]

Bio‐based polymeric materials have recently gained popularity due to their unique properties, including environmental friendliness, biodegradability, and sustainability. In this study, the bio‐based TPUs were successfully synthesized by one‐shot polymerization method, utilizing 100% bio‐based polytrimethylene ether glycol (PO3G) as polyols, 71% bio‐based 1,5‐pentamethylene diisocyanate (PDI) as isocyanates, and 100% bio‐based 1,4‐butanediol BDO as chain extenders. The as‐prepared TPUs, which contained up to 92% bio‐based material were investigated using a variety of analytical methods, including morphological investigations, mechanical testing, thermal analysis, rheological behavior, docking analysis, and cytotoxicity studies. For PPB 3 (1:3:2), PPB 4 (1:4:3), PPB 5 (1:5:4), and PPB 7 (1:7:6), the initial modulus values were 78, 151, 194, and 314 GPa, and the shore‐A hardness values were 92, 93, 93, and 94. Additionally, a notable variation in the degree of phase separation (DPS) of 0.575, 0.647, 0.716, and, 0.738 between hard segment (HS) and soft segment (SS) was noticed among synthesized bio‐based TPUs and an increase in DPS with higher molar ratios corresponded to a higher content of HS. Besides, the bio‐based TPU proved outstanding cell viability results, representing its potential appropriateness for various biomedical applications. Eventually, docking simulations were shown in silico to evaluate the interaction of bio‐based TPU with the DNA gyrase enzyme. Furthermore, the results of bio‐based TPUs demonstrated excellent applications in the production of 3D printing using FDM. We effectively prepared 3D printing to provide a viable answer to environmental concerns. [ABSTRACT FROM AUTHOR]

Soft robots excel in safety and adaptability, yet their lack of structural integrity and dependency on open-curve movement paths restrict their dexterity. Conventional robots, albeit faster due to sturdy locomotion mechanisms, are typically less robust to physical impact. We introduce a multi-material design and printing framework that extends classical mechanism design to soft robotics, synergizing the strengths of soft and rigid materials while mitigating their respective limitations. Using a tool-changer equipped with multiple extruders, we blend thermoplastics of varying Shore hardness into monolithic systems. Our strategy emulates joint-like structures through biomimicry to achieve terrestrial trajectory control while inheriting the resilience of soft robots. We demonstrate the framework by 3D printing a legged soft robotic system, comparing different mechanism syntheses and material combinations, along with their resulting movement patterns and speeds. The integration of electronics and encoders provides reliable closed-loop control for the robot, enabling its operation across various terrains including sand, soil, and rock environments. This cost-effective framework offers an approach for creating 3D-printed soft robots employable in real-world environments. Soft mechanism driven robots, made via multi-material 3D printing, combine soft and rigid components for robust, adaptable locomotion. This framework balances flexibility and strength, enabling effective operation across varied terrains. [ABSTRACT FROM AUTHOR]

Emerging soft systems, including soft robots or wearable devices, actuated by fluidic means facilitate a series of inherent benefits, including safe human-robot interactions, lower costs, and adaptability in geometry for manipulating delicate objects. However, existing fluidic soft systems are facing a critical barrier: how to get rid of traditional rigid, bulky, and redundant fluid power/control components as well as develop their own flexible, portable, and universal fluidic components for implementing fully flexible, multi-circuit, and untethered autonomous systems. Here, we introduce a strategy of flexible electro-hydraulic power chips that enables multi-circuit independent pumping and control of soft systems in simple, compact, and lightweight forms. These electro-hydraulic power chips could be arbitrarily programmed through "line-plane-body" combinations of electro-hydraulic power "diode" or "triode" modules with high output density of 10.77 kPa/g and 2.15 L/min/g, and freely fabricated into the desired shapes and functions via multi-material 3D printing technique. Demonstrations of multi-circuit mass transfer, five-finger selective cooling, bird's multiple actuation, jellyfish's fast swimming show electro-hydraulic power chips' portable, powerful, and multi-circuit independent attributes. The proposed strategy is an important advance towards low-cost, mass-manufactured, and standard universal fluid power components for the next generation of multi-functional, autonomous soft systems. Developing flexible, portable fluidic components for soft systems is challenging due to reliance on rigid, bulky parts. The authors present flexible electro-hydraulic power chips, fabricated via 3D printing, achieving high output density and demonstrating versatile applications. [ABSTRACT FROM AUTHOR]

Vertebrate animals benefit from a combination of rigidity for structural support and softness for adaptation. Similarly, integrating rigidity and softness can enhance the versatility of soft robotics. However, the challenges associated with creating durable bonding interfaces between soft and rigid materials have limited the development of hybrid robots. Existing solutions require specialized machinery, such as polyjet 3D printers, which are not commonly available. In response to these challenges, we have developed a 3D printing technique that can be used with almost all commercially available FDM printers. This technique leverages the common issue of underextrusion to create a strong bond between soft and rigid materials. Underextrusion generates a porous structure, similar to fibrous connective tissues, that provides a robust interface with the rigid part through layer fusion, while the porosity enables interlocking with the soft material. Our experiments demonstrated that this method outperforms conventional adhesives commonly used in soft robotics, achieving nearly 200% of the bonding strength in both lap shear and peeling tests. Additionally, we investigated how different porosity levels affect bonding strength. We tested the technique under pressure scenarios critical to soft and hybrid robots and achieved three times more pressure than the current adhesion solution. Finally, we fabricated various hybrid robots using this technique to demonstrate the wide range of capabilities this approach and hybridity can bring to soft robotics. [ABSTRACT FROM AUTHOR]