Stereolithography Format Research Articles

Mechanical behavior of external root resorption cavities restored with different materials: a 3D-FEA study

BackgroundThe aim was to evaluate the stresses in teeth, with external root resorption (ERR) restored with different materials using finite element analysis (FEA).MethodsIn this study, a Micro-CT scan was conducted on a prepared maxillary central tooth. DICOM-compatible images obtained from the sections were converted into stereolithography format using Ctan software. Utilizing the VRMesh Studio program, a solid model was generated based on the 3D image obtained through micro-CT scanning. External root resorption cavities were strategically designed at the apical, middle, and coronal thirds levels on the buccal surface of the tooth root. Subsequently, these created resorption cavities were restored using Biodentin, mineral trioxide aggregate (MTA), and glass ionomer cement (GIC). The models were devided into 12 groups according to their location,the type of restoration, material used and the null group was added. To allow measurement of Von Mises stress values, a simulated oblique force of 100 N, was applied directed towards the palatal region of the upper central tooth at a 45° angle to the occlusal plane.ResultsThe highest von Mises stress value in the dentin was observed in the unrestored coronal cavity model (99.00 MPa). FEA results demonstrated that using a repair material significantly reduced the stress levels in the dentin. The lowest stress values were seen in cavities restored with Biodentine. The stress values in cavities treated with Biodentine and MTA were found to be similar.ConclusionsRestoring the external resorption cavity in the tooth significantly reduced stress levels in the dentin. Biodentine and MTA absorbed more force, transmitting less stress to the dentin compared to GIC.Clinical relevanceBiodentin and MTA can be used in the repair of external resorption cavities.

Development and validation of a robotic system for milling individualized jawbone cavities in oral and maxillofacial surgery

ObjectivesThis study aimed to develop and validate a robotic system capable of performing accurate and minimally invasive jawbone milling procedures in oral and maxillofacial surgery. MethodsThe robotic hardware system mainly includes a UR5E arm (Universal Robots, Denmark) and the binocular positioning system (FusionTrack 250, Atracsys LLC, Switzerland). The robotic software (Dental Navi 3.0.0, Yakebot Technology Ltd., China) is capable of generating cutting tool paths based on three-dimensional shape description files, typically in the stereolithography format, and selected cutting tool parameters, as well as designing surgical accessories. Fully impacted supernumerary tooth models in the maxilla were fabricated using software and three-dimensional printing. Following the planning of a customized cavity to fully expose the tooth, maxillary bone milling was performed on both the robot and static guide groups (n = 8). After milling, all models underwent scanning for assessment. ResultsIn the experiment with fully buried supernumerary tooth models in the maxilla, the root mean square, translation error, over-removal rate, and maximum distance were significantly smaller in the robot group compared to the static guide group. Moreover, the overlap ratio and Dice coefficient were significantly greater in the robot group. No statistically significant differences were observed between the two groups in terms of the rotation error (P = 0.80) or under-removal rate (P = 0.92). ConclusionsThis study has developed a robotic system for milling individualized jawbone cavities in oral and maxillofacial surgery, and its accuracy has been preliminarily verified to meet clinical requirements. Clinical significanceThe robotic system can achieve precise, minimally invasive, individualized jawbone milling in a variety of oral and maxillofacial surgeries, including tooth autotransplantation, surgical reshaping for zygomatic fibrous dysplasia, removal of fully impacted supernumerary or impacted teeth, and endodontic microsurgery, among other relevant clinical applications.

Development of colonic stent simulator using three-dimensional printing technique: a simulator development study in Korea.

Colonic stenting plays a vital role in the management of acute malignant colonic obstruction. The increasing use of self-expandable metal stents (SEMS) and the diverse challenges posed by colonic obstruction at various locations underscore the importance of effective training for colonic stent placement. All the components of the simulator were manufactured using silicone molding techniques in conjunction with three-dimensional (3D) printing. 3D images sourced from computed tomography scans and colonoscopy images were converted into a stereolithography format. Acrylonitrile butadiene styrene copolymers have been used in fused deposition modeling to produce moldings. The simulator replicated the large intestine from the rectum to the cecum, mimicking the texture and shape of the human colon. It enables training for colonoscopy insertion, cecum intubation, loop reduction, and stenting within stenotic areas. Interchangeable stenotic modules for four sites (rectum, sigmoid colon, descending colon, and ascending colon) were easily assembled for training. These modules integrate tumor contours and blood vessel structures with a translucent center, allowing real-time visualization during stenting. Successful and repeatable demonstrations of stent insertion and expansion using the reusable SEMS were consistently achieved. This innovative simulator offers a secure colonic stenting practice across various locations, potentially enhancing clinical outcomes by improving operator proficiency during actual procedures.

Three-dimensional anatomical analysis of the optic nerve canal with virtual model based on CBCT

The optic nerve canal (ONC) is a fine skeletal structure that contains the optic nerve. However, it has not been thoroughly examined. This necessitates establishing a baseline knowledge of the geometrical and volumetric parameters of the ONC. The data of twenty patients who received a cone beam computed tomography examination were prepared using a voxel-based segmentation. The measurement was performed separately by two examiners on virtual skull models in stereolithography format in Geomagic Wrap®. The results showed that the volume of the ONC varied between 92.48 mm3 and 162.7 mm3 (M = 123.46 mm3, SD = 26.61 mm3). Sex-specific statistically significant differences in volume were detected only for the right side. The angle of the ONC to the skull base was independent of the diameter of the canal. Both the intrarater and interrater comparisons of the measurements showed high values of reproducibility of the results. This study showed that a virtual anatomical model provides a feasible and reliable method to investigate the ONC. The examination technique could have a wider range of application in anthropology and application in clinical medicine. Advances in the automation of radiological diagnostics and the digital analysis of X-ray images could help to reduce examination times.

A Cost-Affordable Methodology of 3D Printing of Bone Fractures Using DICOM Files in Traumatology

Three-dimensional (3D) printing has gained popularity across various domains but remains less integrated into medical surgery due to its complexity. Existing literature primarily discusses specific applications, with limited detailed guidance on the entire process. The methodological details of converting Computed Tomography (CT) images into 3D models are often found in amateur 3D printing forums rather than scientific literature. To address this gap, we present a comprehensive methodology for converting CT images of bone fractures into 3D-printed models. This involves transferring files in Digital Imaging and Communications in Medicine (DICOM) format to stereolithography format, processing the 3D model, and preparing it for printing. Our methodology outlines step-by-step guidelines, time estimates, and software recommendations, prioritizing free open-source tools. We also share our practical experience and outcomes, including the successful creation of 72 models for surgical planning, patient education, and teaching. Although there are challenges associated with utilizing 3D printing in surgery, such as the requirement for specialized expertise and equipment, the advantages in surgical planning, patient education, and improved outcomes are evident. Further studies are warranted to refine and standardize these methodologies for broader adoption in medical practice.

Segmental Mandibulectomy and Mandibular Reconstruction with Fibula-Free Flap Using a 3D Template.

The present study evaluates the influence of virtual surgical planning with a preoperative 3D resin model on aesthetic and functional outcomes in patients treated by segmental mandibulectomy and reconstruction with fibula-free flap for oral cancer. All consecutive patients who underwent segmental mandibulectomy and mandibular reconstruction with a fibula-free flap using a 3D template at our department from January 2021 to January 2023 were included in the study. "Patients control" were patients treated by reconstruction with a fibula-free flap without using a 3D template. Three-dimensional modeling was performed by converting from preoperative computed tomography to a stereolithography format to obtain the resin 3D models. Qualitative analysis of anatomical and aesthetic results consisted of the evaluation of the patients' aesthetic and functional satisfaction and the symmetry of the mandibular contour observed at clinical examination. Quantitative analysis was based on the assessment of the accuracy and precision of the reconstruction by comparing preoperative and postoperative computed tomograms as objective indicators. Seven patients (five males and two females, mean age of 65.1 years) were included in the study. All patients showed a symmetric mandibular contour based on the clinical examination. After recovery, six patients (85.7%) considered themselves aesthetically satisfied. The quantitative analysis (assessed in six/seven patients) showed that the mean difference between preoperative and postoperative intercondylar distance, intergonial angle distance, anteroposterior dimension, and gonial angle improved in the 3D template-assisted group. The 3D-printed template for mandibular reconstruction with microvascular fibula-free flap can improve aesthetic outcomes in comparison with standard approaches.

Shape optimization of embedded solids using implicit Vertex-Morphing

One of the biggest challenges in optimizing the shape of complex solids is the requirement to maintain a reasonable mesh quality not only at the boundary but also for the bulk discretization of the interior. Thus, additional regularization and, in many cases, re-meshing of the structure during the iterative process is unavoidable with a Lagrangian description. By tracking the shape update using an Eulerian representation, embedded boundary methods are a promising technique for eliminating mesh distortion problems.This work consistently combines the unique features of implicit Vertex-Morphing and embedded boundary methods, facilitating the node-based shape optimization of solids with industrial complexity. One of the crucial elements for solving the primal problem on a fixed background grid is an efficient and robust quadrature scheme. To this end, we incorporate the open-source C++ framework QuESo (https://github.com/manuelmessmer/QuESo) developed for the numerical integration of arbitrarily complex embedded solids defined by oriented boundary meshes, e.g., in STereoLithography (STL) format. Meanwhile, applying the Helmholtz/Sobolev-based (implicit) filter to the vertices of the embedded boundary mesh not only exploits the extensive design space of node-based optimization but also ensures robust control over the feature size. To realize the above methodology, this work introduces a novel sensitivity analysis that yields mesh-independent shape gradients with respect to the immersed boundary. Through a specific sensitivity weighting, we recover a continuous gradient field from discrete values calculated at the nodes of the background grid. In addition, the presented workflow ensures robust enforcement of challenging geometrical constraints, including minimum wall thicknesses and design space limitations.We critically assess our approach with benchmarks and structures of industrial relevance. In all examples, trivariate B-Spline bases span the background grid, providing highly accurate finite element solutions and shape sensitivities at every iteration. Moreover, the elimination of mesh distortion problems enables a successful termination at the local optimum, even for large shape modifications.

Fabrication of electrical devices on conformal surfaces based on array nozzle and five-axis motion mechanism

It has been known that conformal printing with a single nozzle has low efficiency. This study proposes a novel non-expandable curved surface printing method that could realize high-efficiency printing with array nozzles. First, based on the non-uniform rational B-splines curved surface reconstruction method, the parameter equation of the stereolithography format curved surface model is obtained. An equidistant parallel curve filling method is proposed based on the parameter equation. According to the filling accuracy, a spatial equidistant curve network model is established by fitting the surface. Using each node on the curve network as the filling pixel increases the filling rate of the non-expandable surface and improves the printing accuracy. Compared with that of the traditional equidistant filling, the droplet filling rate could be increased by 13.05 % in this study. Finally, based on the self-developed five-axis curved surface inkjet printing system and normal vector printing method, samples of concave, convex, and multi-material conformal surfaces are sequentially printed. Our research finding lays the foundation for high-efficiency integrated molding of electronic devices with complex conformal surfaces.

Puncture and Drainage Surgery for Intracerebral Hemorrhage Guided by 3D Printing Puncture Guide Plate.

Accurate puncture is the key to ensure the effect of puncture and drainage surgery for intracerebral hemorrhage. It usually uses CT to guide the drainage tube to reach the center of the hematoma cavity, which has the problems of inaccurate positioning using 2D images and high requirements for surgeon's experience in brain anatomy and imaging diagnosis. The aim of this study was to use a 3D printing puncture guide plate to guide the puncture and drainage surgery for intracerebral hemorrhage. The CT images were imported into 3D Slicer software to reconstruct 3D models of the head skin and intracerebral hematoma. The target was set in the center of the hematoma and the puncture path from the target to the entry point was designed, the 3D model of puncture guide plate was constructed and saved as stereolithography format file, which was imported into 3D printer to print. During surgery, the drainage tube was placed in the center of the hematoma guided by the 3D printing puncture guide plate, and the blood clot was extracted by the suction syringe. Eight patients with hypertensive intracerebral hemorrhage were treated with puncture and drainage surgery guided by 3D printing puncture guide plate. The average operation time of the 8 surgeries was 17.63 minutes. The drainage tubes were all precisely placed in the center of the hematoma, and the blood clots were all successfully extracted. The positioning errors of the 8 drainage tubes were between 1.76mm and 2.68mm, and the mean value was 2.10±0.32mm. The hematoma clearance rate of the 8 patients was between 74.18% and 96.73%, and the mean value was 85.14±6.71%. The puncture and drainage surgery for intracerebral hemorrhage guided by 3D printing puncture guide plate helps to quickly and effortlessly localize intracerebral hematoma and achieves satisfactory hematoma clearance rate.

Feasibility of Easy to Use and Inexpensive Three-Dimensional Printed Educational Model of Temporal Bone: Practiced Without Drilling.

Three-dimensional (3D) printed temporal bone model draws great attention as a promising alternative for conventional cadaveric model in education of otologic surgery. However, its high price and requirement for specialized tools hinder widespread use. We devised a simple educational model based on lattice structure to overcome these problems and compared it with a commercial model. We converted high-resolution temporal bone computed tomography images into stereolithography format, and printed it using the G005 3D printing system from CUBICON©. In this process, the part to be drilled out was made of lattice structure. We evaluated the model by a questionnaire prepared in advance, and compared the results with those of a commercial model. We created an educational 3D printed temporal bone lattice model one-tenth the cost of commercial temporal bone. Our model reproduced the important structures of the temporal bone, produced less dust, and had similar strength and grinding sensation compared to the commercial model. The surface texture and reproducibility were comparable to the commercial model. Although most of structures were remodeled more elaborately in the commercial model than our model, our model demonstrated significant potential as a cost-effective educational tool for medical students and residents. 3D printed temporal bone lattice model has potential for widespread use due to low cost and easy accessibility. Further improvements in the fine structures of the temporal bone are necessary to enhance its utility as an educational model.

CBCT Imaging for Bracket Positioning with Consideration to Root Axes

Cone-beam computed tomography (CBCT) imaging and computer-aided manufacturing were used to produce stereolithographic trays for indirect-direct bonding. The ability to align teeth considering both the crown and the root decreases the chances for post treatment relapse. Three-dimensional (3D) images for separate brackets in a bracket kit were obtained from CBCT scanning in DICOM format and then converted to stereolithography format using Mimics software. Another CBCT image was obtained for the patients’ dentition. The images were saved in DICOM format and then placed into the Mimics image processing software. The images were enhanced, and the teeth were isolated to gain a clear view of their roots. With both images in the Mimics image-processing software, each bracket was placed on its designated tooth and positioned accurately. After the brackets were placed, a 3D image of a U-shaped stent was added to the project. Then, the image of the stent was placed over the teeth and half of the brackets. In the Mimics software, the teeth and brackets were then subtracted from the image of the tray to have a negative replica. The subtracted image of the tray in stereolithography format was printed with a 3D printer to obtain a 3D printed bracket positioning tray with indentations for bracket seating. This allowed brackets to be seated on the tray and bonded using conventional bonding steps.

A generative design method based on spline scanning for additive manufacturing

While additive manufacturing (AM) provides design flexibility, challenges persist in handling intricate freeform shapes, especially those laden with fine details. Conventional AM processes, such as slicing stereolithography (STL) format models, generating line segment toolpaths, and polyline-based printing, prove costly and compromise accuracy. This paper proposes a solution: the spline scanning generative design method. Utilizing spline patterns to construct smooth toolpaths directly, it enables seamless curved printing, significantly reducing computational expenses while maintaining high accuracy through spline control points. Experimental implementation, supported by dedicated algorithms, attests to its efficacy, emphasizing its potential for intricate freeform structure design and printing.

An immersed moving boundary for fast discrete particle simulation with complex geometry

An immersed moving boundary (IMB) scheme in LBM-DEM is proposed for discrete particle simulation with arbitrarily complex geometry. Momentum exchange between fluid and unresolved particles can be exerted by a modified weighting function with drag force and a new solid operator in IMB, which can describe both particle–fluid interaction and complex geometry, and requires only local information in perspective of solution. Combined with stereolithography (STL) format for describing complex geometry, a GPU-based LBM-DEM-IMB is implemented, and its ability and accuracy for complex geometry from STL model is verified by simulating flow past a stationary sphere. Compared with CFD-DEM in discrete particle simulations of both fluidized bed with immersed tube and aerosol transporting in human nasal, proposed method has much higher efficiency and maintains comparable accuracy in dense and dilute particle–fluid systems with complex geometry, which demonstrates it to be a promising computational strategy for particle–fluid two-phase flows.

Complex-geometry simulations of transient thermoelasticity with the Shifted Boundary Method

We propose a formulation of the Shifted Boundary Method, an immersed/embedded/unfitted boundary method, for transient thermo-elasticity problems characterized by very complex geometries. With an extensive set of numerical experiments, we demonstrate that the SBM performs accurately and robustly, even when the geometry is represented in stereolithography format (STL, or Standard Tessellation Language) with gaps and overlaps. We conclude with a thermoelastic analysis of an advanced fluid tank design, obtained with topology optimization methodologies and a candidate for additive manufacturing processes. This final example represents what is foreseen as the typical application of the SBM in the context of the simulation of additively manufactured components.

Endodontic microsurgery virtual reality simulation and digital workflow process in a teaching environment.

Computer simulations are stimulating increased attention in dentistry. Augmented reality superimposes a virtual scenario over an existing reality and allows interaction with it. Virtual reality (VR) simulates a fully immersive situation permitting the user to experience the full environment in real time. Haptic technology provides tactile and realistic force feedback for the user to experience the immersive situation as if they were really there. Preclinical training is important to gain familiarity with difficult surgical techniques and to implement interpersonal skills. Developing a valid assessment of surgical simulation is challenging. This paper wants to present a newly realized VR simulation in endodontic microsurgery through the developmental digital workflow, the demonstration of a haptic VR scenario and student self-assessment and self-reflection feedback. The volumes were exported in a stereolithography format to prepare and optimize in terms of shape and shade for the VR simulation. The graphics and touchable haptic solid were created using Virteasy Editor, which allows the transformation of 3D surfaces into graphical and volumetric haptic solids depending on their material (enamel, dentine, pulp and bone). Users were asked to execute the osteotomy and root-resection preparation. The assessment criteria were determined, and the feedback statements were created by a questionnaire with fixed answers. Objective and qualitative criteria for assessing the preparation were obtained from the literature. This study provides proof that it is possible to provide reliable and clinically relevant qualitative feedback with a VR simulator. VR simulation offers an innovative approach with all the benefits of clinical experience. It permits you to save your own progress and review the assessment at any time.

USE OF 3D-PRINTED FRACTURE MODELS VERSUS SAWBONES FOR SURGICAL RESIDENT TRAINING: A FEASIBILITY STUDY

Conventional fracture courses utilise prefabricated sawbones that are not realistic or patient specific. The aim of this study is to determine the feasibility of creating 3D fracture models and utilising them in fracture courses to teach surgical technique.We selected an AO type 2R3C2 fracture that underwent open reduction internal fixation. De-identified CT scan images were converted to a stereolithography (STL) format. This was then processed using Computer Aided Design (CAD) to create a virtual 3D model. The model was 3D printed using a combination of standard thermoplastic polymer (STP) and a porous filler to create a realistic cortical and cancellous bone. A case-based sawbone workshop was organised for residents, unaccredited registrars, and orthopaedic trainees comparing the fracture model with a prefabricated T-split distal radius fracture. Pre-operative images aided discussion of fixation, and post-operative x-rays allowed comparison between the participants fixation. Participants were provided with identical reduction tools. We created a questionnaire for participants to rate their satisfaction and experience using a Likert scale.The 3D printed fracture model aided understanding and appreciation of the fracture pattern and key fragments amongst residents and unaccredited trainees. Real case-based models provided a superior learning experience and environment to aid teaching. The generic sawbone provided easier drilling and inserting of screws. Preliminary results show that the cost of 3D printing can be comparable to generic sawbones.It is feasible to create a fracture model with a real bone feel. Further research and development is required to determine the optimum material to use for a more realistic feel.The use of 3D printed fracture models is feasible and provides an alternative to generic sawbone fracture models in providing surgical training to residents.

Finite Element Analysis of Stress Distribution in Root Canals When Using a Variety of Post Systems Instrumented with Different Rotary Systems.

It is very important for clinicians to provide restorative treatments that provide durability for endodontically treated teeth. Trauma, occlusal premature contact, and features of teeth are some of the issues that can cause vertical root fractures (VRFs) in root canal-treated teeth. The aim of this 3-D study was to compare stress distribution on mandibular premolar teeth when using a variety of post designs instrumented with different rotary systems. Six mandibular premolar teeth were instrumented with the following tools: ProTaper Next, WaveOne (WO), Reciproc (R), ReciprocBlue (RB), F6-Skytaper, and TF-Adaptive. Teeth were scanned using cone beam computed tomography (CBCT) and the images were transferred to the Catia V5R25 software. Data were recorded in a stereolithography (STL) format. Four different post systems were used, fabricated from metal, fiber, zirconia, and titanium, respectively. Dentin, gutta, post, core, and crown models were added to the solid model. ANSYS V17.2 finite element analysis (FEA) software was used to determine stress distribution on each assembly. Finite analysis models were created that allowed for the calculation of stress distribution of 250-N loading at a 45° angle and vertical in relation to the roots. The maximum principal stress and von Mises values were higher under oblique loading on the roots. The F6-Skytaper and WO systems showed lower stress than other systems. The TF-Adaptive instrument showed higher stress distribution than the other models. Fiber and titanium posts showed lower stress than others. The F6-Skytaper, R, and RB instruments were found to be most effective in terms of displacement of the crown, resulting in the lowest stress values. Fiber and titanium posts showed better results than other post systems, while root canals instrumented with the F6-Skytaper and WO instruments were less likely to result in root fractures.

Evaluating the accuracy of intraoral direct digital impressions in 2 infants with unilateral cleft lip and palate compared with digitized conventional impression

Presurgical infant orthopedics was introduced as an interceptive approach for treating cleft lip and/or palate (CLP). This study aimed to evaluate the intraoral digital impression technique as a viable alternative to conventional impression in infants with unilateral CLP. Trios 3-Shape scanner (3Shape, Copenhagen, Denmark) was used for intraoral scanning of the infants' maxillary arches to provide a direct digital scan (DDS). In addition, conventional impressions of the same patients were taken in a hospital setting, and the resultant stone models were digitized using the same scanner to create an indirect digital scan (IDS). Both scans (DDS and IDS) were exported in stereolithography format, and the resultant stereolithography files were imported into computer-assisted-design software (Exocad DentalCAD; exocad GmbH, Darmstadt, Germany) for 3-dimensional surface model superimposition. Differences between the 2 surfaces were quantified in millimeters and visually displayed by a color map. Three-dimensional surface model superimposition of the DDS and IDS scans showed an excellent agreement between both approaches, in which differences ranged from 0.01 mm to 0.1 mm CONCLUSIONS: Intraoral direct digital impression in infants with unilateral CLP is a safe, accurate, and time-efficient technique, which can be a viable alternative to conventional impression. This will aid in overcoming the challenges and complications that are frequently associated with using conventional impressions in infants with unilateral CLP, thus reducing the burden of care not only on the patients' families but also on the care providers.

3D printing for orbital volume anatomical measurement.

The aim was to develop a method for reproducible orbital volume (OV) measurement in vivo based on 3D printing. Twelve orbits were obtained from dry skulls of the Human Anatomy Department of Lille University. Computer tomography (CT) slice images of these orbits were transformed into stereo-lithography (STL) format and 3D-printed. Bone openings were closed using either putty and cellophane after printing (3D-Orb-1) or at the printing stage in silico using MeshMixer (3D-Orb-2). The results were compared with those of the conventional water-filling method as a control group (Anat-Orb). The observers reported a mean orbital volume of 21.3 ± 2.1 cm3 for the open-skull method, 21.2 ± 2.4 cm3 for the non-sealed 3D-printing method, and 22.2 ± 2.0 cm3 for the closed-print method. Furthermore, the intraclass correlation coefficients (ICCs) showed excellent intra-rater agreement, i.e., an ICC of 0.994 for the first observer and 0.998 for the second, and excellent interobserver agreement (ICC: 0.969). The control and 3D-Orb-1 groups show excellent agreement (ICC: 0.972). The 3D-Orb-2 exhibits moderate agreement (ICC: 0.855) with the control and appears to overestimate orbital volume slightly. Our 3D-printing method provides a standardized and reproducible method for the measurement of orbital volume.

Thermal efficiency of open-cell metal foams: Impact of foam thickness by comparing correlations and numerical modeling

• Numerical techniques were used to analyze the extended surface efficiency and the impact of the foam's thickness. • It was considered copper and nickel foams with different thicknesses and two dielectric fluids, HFE-7100 and Ethanol. • The foam efficiency increases as the thickness decreases. • The Cu foam shows higher foam-finned efficiency than the Ni foam. • Metal foam under pool boiling of HFE-7100 has higher efficiency than pool boiling using Ethanol. • The classical pin fin model with an adiabatic tip was the one that most suitably represents the efficiency of the foams. Engineered surfaces are increasingly used to cool electronic devices with dielectric fluids in two-phase change. A common type of such surfaces is the open-cell metal foam. In this work, our goal was two-fold, to assess the influence of the thickness of the foam and which models of foam-finned efficiency can be most suitably used to predict their thermal efficiency. Numerical simulations of heat conduction in open-cell metal foams were carried out in foam-extend-4.0. Copper and nickel foams with three different thicknesses, 3 mm, 2 mm, and 1 mm, were used in the simulations under convective boundary conditions obtained from pool boiling experiments with two dielectric fluids, HFE-7100 and Ethanol, at saturation conditions and atmospheric pressure. The geometries of the foams were segmented from μCT images, converted to the stereolithography (STL) format, and used to build the computational meshes. The numerical extended surface efficiency was compared with classical analytical models and other correlations from the literature. The foam efficiency increased as the thickness decreased, i.e ., the thinnest foams showed better efficiency than the other ones. Metal foam under pool boiling of Ethanol had lower efficiency than HFE-7100. The pin fin model with adiabatic tip exhibited the lowest mean absolute error, lower than 10% for copper foams and 20% for nickel foams; the copper foam with 1 mm and HFE-7100 had the lowest error, approximately 1%. Therefore, this model could be used as a guide during the design step to determine the metal foam characteristics of a cooling system. On the other hand, the models that consider a three-dimensional matrix presented errors higher than 30%.