Shape Matching between Printed 3D Model and Digital 3D Model based on 2D views and Zernike Moments

The aim of study was to evaluate the efficacy of the use of three-dimensional (3D) printing model for preoperative planning in treatment of tibial plateau fracture. Besides, we also investigated the effect of 3D printing technology on the communication between doctors and patients. Thirty-three patients with tibial plateau fractures were enrolled in the study from March 2022 to July 2023. A 3D digital model of each tibial plateau fracture was constructed, and the individual model was exported to a 3D printer for the construction of a full solid model. This 3D-printing model, along with the Three-Column classification, was utilized to plan the operation. During each operation, the operative time and amount of blood loss were recorded as primary outcome measures. Patients were followed to evaluate surgical outcomes using Rasmussen scores and radiological evaluation, which served as secondary outcome measures. Additionally, satisfaction for patients was assessed using questionnaires developed by Yiting Lou. Two-column fractures accounted for the highest proportion at 45.5%. Isolated posterior column fractures constituted 9.1%. The average 3D printing time was 7.1 ± 0.9 h; a material cost of 1 USD per model. Complex fracture cases had significantly longer 3D printing times (p = 0.001) and provided more information to the surgical team than simple fractures. Patient satisfaction with 3D models was rated at 7.4 ± 0.7 out of 10 points. Malalignment and gap width were not correlated with surgical time (p = 0.3 and 0.2). The infection rate was 3%, and the rate of secondary loss of reduction at six months was 25%, with no correlation with Rasmussen scores (P > 0.05, Fisher’s test). Our study revealed that 3D printing models effectively assist the surgeons in planning operations, especially in complex cases, and may enhances communication between surgeons and patients. Follow-up 6 months after surgery showed good knee function.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-30475-7.

With the rapid development of 3D printing technology and the continuous breakthrough of new material technologies, 3D printing has received more and more attention in the fields of industry, medical, sports, and education. In the cloud manufacturing environment, how to efficiently manage 3D printing models is a critical issue that needs to be solved urgently. The paper begins with a study of 3D printing model aggregation and retrieval mechanism based on this problem. Firstly, we devised a set of 3D printing model management framework with high scalability. Under this framework, a meta-model library and feature library are established to realize the aggregation of 3D printing models. Then, we developed a sketch-based 3D model retrieval method, which can help platform users to create and retrieve personalized 3D printing models easily. This study provides new ideas and a reference pattern for the model design and retrieval methods of existing commercial 3D printing platforms.

Understanding normal structural and functional anatomy is critical for health professionals across various fields such as medicine, veterinary, and dental courses. The landscape of anatomical education has evolved tremendously due to several challenges and advancements in blended learning approaches, which have led to the adoption of the use of high‐fidelity 3D digital models in anatomical education. Cost‐effective methods such as photogrammetry, which creates digital 3D models from aligning 2D photographs, provide a viable alternative to expensive imaging techniques (i.e. computed tomography and magnetic resonance imaging) whilst maintaining photorealism and serving multiple purposes, including surgical planning and research. This study outlines a comprehensive workflow for producing realistic 3D digital models from embalmed veterinary specimens. The process begins with the preservation of specimens using the modified‐WhitWell (WhitWell‐Liverpool) embalming protocol, which ensures optimal tissue rigidity and improved colour enhancement, facilitating easier manipulation and better photogrammetry outcomes. Once embalmed, specimens are photographed to create digital 3D models using photogrammetry. Briefly, all images are processed to generate a sparse point cloud, which is then rendered into a 3D mesh. The mesh undergoes decimation and smoothing to reduce computational load, and a texture is applied to create a lifelike model. Additional colour enhancements and adjustments are made using digital tools to restore the natural appearance of the specimens. The 3D models are stored on a cloud repository and integrated into the University of Liverpool's Virtual Learning Environment, providing continuous, remote access to high‐quality anatomical resources. The switch to embalmed specimens during the COVID‐19 pandemic allowed for longer‐term use and detailed dissections, enhancing the quality of digital models. Fresh specimens, though naturally coloured, are less stable for photogrammetry, making embalmed specimens preferable for accurate 3D modelling. Our method ensures embalmed specimens are rigid enough for precise modelling while allowing texture adjustments to enhance digital representation. This approach has improved logistical efficiency, educational delivery, and specimen quality. Innovative embalming techniques and advanced photogrammetry have the power to revolutionise anatomical education with the creation of a vast digital library accessible online to students at any time. This approach paves the way for integrating digital 3D models into immersive environments and assessing their impact on learning outcomes.

Despite inherent errors, cephalometric superimpositions are currently the most widely used means for assessing sagittal and vertical tooth movements. The purpose of this study was to compare three-dimensional (3D) digital model superimposition with cephalometric superimposition. The material was collected from initial and final maxillary casts and lateral cephalometric radiographs of 30 patients (6 males, 24 females, mean age 17.7 years) who underwent orthodontic treatment with extraction of permanent teeth. Each pair of cephalograms was traced and superimposed according to Ricketts' four-step method. 3D scanning of the maxillary dental casts was performed using INUS dental scanning solution(R), which consists of a 3D scanner, an autoscan system, and 3D reverse modelling software. The 3D superimposition was carried out using the surface-to-surface matching (best-fit method) function of the autoscan system. The antero-posterior movement of the maxillary first molar and central incisor was evaluated cephalometrically and on 3D digital models. To determine whether any difference existed between the two measuring techniques, paired t-tests and correlation analysis were undertaken. The results revealed no statistical differences between the mean incisor and molar movements as assessed cephalometrically or by 3D model superimposition. These findings suggest that the 3D digital orthodontic model superimposition technique used in this study is clinically as reliable as cephalometric superimposition for assessing orthodontic tooth movements.

PurposeThe aim of this study was to determine the efficacy of using 3D printing models in the learning process of orbital anatomy and pathology by ophthalmology residents.MethodsA quasi-experimental study was performed with 24 residents of ophthalmology at Mashhad University of Medical Sciences. Each stratum was randomized into two groups. The educational booklets were distributed, and various forms of orbital 3D models were printed from orbital computed tomography (CT) scans. Knowledge enhancement on the topics was measured by comparing pretest and posttest scores.Results Thirteen residents who were trained using traditional methods were deemed the control group; while 11 residents who were trained using the 3D printed models were classed as the intervention group. The control group was younger than the intervention group (P = 0.047). The results showed that there was a statistically significant difference in the total posttest scores between the two groups. Based on the repeated measures of the analysis of variance (ANOVA), score variables were significant between the two groups (P = 0.008). Interestingly, the use of the 3D educational model was more effective and statistically significant with the year one residents as compared to the year two residents (P = 0.002).ConclusionThis study is the first one in Iran quantifying the effects of learning using 3D printed models in medical education. In fact, 3D modeling training is seemingly effective in teaching ophthalmic residents. As residents have never encountered such technology before, their experience using 3D models proved to be satisfactory and had a surprising positive effect on the learning process through visual training.

The goal of this study is to show the process for obtaining a 3D model of a canine tibia using free software from clinical quality computed tomography (CT) images. In this case, the obtained model was used for generating a computer simulation with the Finite Element Method (FEM) and for generating a 3D printed canine tibia. First, a real canine tibia was scanned in order to generate Dicom (Digital Imaging and Communication on Medicine) CT images. Using the open source 3D Slicer, the Dicom CT images, the cortical and trabecular bones were segmented to construct to build a first 3D tibia model. The defects of this first 3D model were examined, and its surfaces were smoothed using open source MeshMixer software. Subsequently, the smoothed 3D tibia model was exported to STL file (Standard Triangle Language), and then imported to Mentat-Marc FEM software in which uniform tetrahedral elements meshes for the trabecular and cortical bones were generated. These 3D meshes were used to develop a Finite Element Analysis for studying the mechanical stiffness of the tibia. Also, the stl file obtained was imported to the Wanhao cura v.18.04 software, and the G-code file were created. Finally, a 3D canine tibia model was printed in a Wanhao Duplicator 6 3D printer with ivory-colored PLA. This 3D printed model was used for later for educational training.KeywordsTibiaComputerized axial tomographyCanineCorticalTrabecularFEM3D printed model

Developing an accurate onboard‐camera pose estimation is one major challenge of satellite systems, and the attempt of improving remote sensing camera pose accuracy never ceases. The camera pose can be recovered by aligning a captured 2D image and a 3D digital surface model of the corresponding scene. In this paper, a novel camera pose estimation method from captured images with the over known real scene 3D products is proposed to enhance remote sensing camera attitude accuracy. The purpose of this estimation is to determine the pose of a camera purely from an image based on a known 3D model, where 3D products of very high spatial resolution are projected onto image space by virtual camera system with error‐contained initial exterior orientation parameters, and whether the pose of the camera can be determined precisely depends on the 2D–3D registration result. The process consists of two steps: (1) feature extraction and (2) similarity measure and registration. Furthermore, the proposed method revises the rotation matrix and translation vector by utilizing formulation based on quaternion representation of rotation, respectively. We evaluate our method on challenging simulation data and results show that acceptable accuracy of camera pose can be achieved.

Objective: To study the clinical efficacy of digital design combined with three-dimensional (3D) printing model minimally invasive extraction of complex impacted mandibular third molars. Methods: Eight patients who visited the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology from April 2023 to March 2024 were included, including 3 males and 5 females, aged from 27 to 57 years old. The impacted mandibular third molars of all patients were closely related to the mandibular canal, and part of the dental tissue entered the mandibular canal. Preoperative digital design was used to simulate the intraoperative tooth segmentation and bone removal operation of the power system and the segmented tooth dislocation path, and analyze the tooth extraction resistance. The mandibular teeth, mandibular canal and mandibular model were three-dimensionally printed using light-curing resin inkjet. During the operation, an endoscope was used combined with the 3D printed model to minimally invasively extract the impacted mandibular third molar. Quantitative sensory testing of the patient's lower lip skin on the operated side was performed before surgery, 2 days after surgery, and 7 days after surgery. Clinical data such as operation time were collected. A paired sample t test was performed on the 2 and 7 days postoperative data and the preoperative data to compare the data differences. Results: All 8 patients successfully completed preoperative design, model printing and minimally invasive surgery. The number of teeth segmented in the preoperative design was (4.4±1.3), and the number of teeth segmented in the actual operation was (4.0±1.1). The operation time was (33.3±13.0) min. None of the patients had postoperative numbness of the lower lip or other postoperative complication. It was observed endoscopically that the inferior alveolar neurovascular bundle was exposed in the extraction socket during the operation. The patient's pressure pain threshold 2 days after surgery (0.601±1.170) was significantly lower than before surgery (1.251±1.109) (t=2.83, P=0.025). Conclusions: For complicated impacted mandibular third molars, digital design combined with 3D printing model can be used to perform minimally invasive extraction with the assistance of an endoscope.

The aim of this study was to evaluate the usefulness of a personalized 3D-printed thyroid model that characterizes a patient’s individual thyroid lesion. The randomized controlled prospective clinical trial (KCT0005069) was designed. Fifty-three of these patients undergoing thyroid surgery were randomly assigned to two groups: with or without a 3D-printed model of their thyroid lesion when obtaining informed consent. We used a U-Net-based deep learning architecture and a mesh-type 3D modeling technique to fabricate the personalized 3D model. The mean 3D printing time was 258.9 min, and the mean price for production was USD 4.23 for each patient. The size, location, and anatomical relationship of the tumor and thyroid gland could be effectively presented using the mesh-type 3D modeling technique. The group provided with personalized 3D-printed models showed significant improvement in all four categories (general knowledge, benefits and risks of surgery, and satisfaction; all p < 0.05). All patients received a personalized 3D model after surgery and found it helpful to understand the disease, operation, and possible complications and their overall satisfaction (all p < 0.05). In conclusion, the personalized 3D-printed thyroid model may be an effective tool for improving a patient’s understanding and satisfaction during the informed consent process.

Early predator detection is a key component of the predator-prey arms race and has driven the evolution of multiple animal hearing systems. Katydids (Insecta) have sophisticated ears, each consisting of paired tympana on each foreleg that receive sound both externally, through the air, and internally via a narrowing ear canal running through the leg from an acoustic spiracle on the thorax. These ears are pressure-time difference receivers capable of sensitive and accurate directional hearing across a wide frequency range. Many katydid species have cuticular pinnae which form cavities around the outer tympanal surfaces, but their function is unknown. We investigated pinnal function in the katydid Copiphora gorgonensis by combining experimental biophysics and numerical modelling using 3D ear geometries. We found that the pinnae in C. gorgonensis do not assist in directional hearing for conspecific call frequencies, but instead act as ultrasound detectors. Pinnae induced large sound pressure gains (20–30 dB) that enhanced sound detection at high ultrasonic frequencies (>60 kHz), matching the echolocation range of co-occurring insectivorous gleaning bats. These findings were supported by behavioural and neural audiograms and pinnal cavity resonances from live specimens, and comparisons with the pinnal mechanics of sympatric katydid species, which together suggest that katydid pinnae primarily evolved for the enhanced detection of predatory bats.

Background/Objectives: The possibilities of endovascular and minimally invasive treatment of visceral and renal artery aneurysms require precise procedure planning. Accurate visualization of vascular pathologies is crucial in this regard. Expanding diagnostic imaging with real 3D models is one of these methods. The objective of our study was to evaluate the utility of 3D printing and virtual 3D models in visualizing visceral and renal artery aneurysms. Methods: A group of 30 patients with true aneurysms of the visceral and renal arteries was selected based on computed tomography angiography (CTA). Aneurysm morphology, diameters, arterial diameters, and anatomical vessel variants were analyzed. Imaging data were processed and 3D-printed using Fused Filament Fabrication (FFF) technology. The resulting 3D models were measured, and dimensional deviations were compared to radiological images. Results: The cohort included 51 aneurysms across arteries supplying abdominal organs, with splenic artery aneurysms (49%) and renal artery aneurysms (25.5%) predominating. Half of the patient group had multiple aneurysms, and 36.7% exhibited anatomical arterial variants. Forty-three 3D models of visceral and renal artery aneurysms were generated, accurately depicting isolated vascular pathologies and the course of visceral arteries in regions of interest. Measurement analysis confirmed that the 3D-printed models showed a mean dimensional deviation of 0.24 mm compared to radiological images. Conclusions: 3D-printed and virtual models enhance the analysis of vascular pathologies, significantly improving the assessment of pathological changes and visualization of anatomical details, especially in hilar aneurysms and aneurysm branches.

The 3D (three-dimensional) modeling has become an important digital and information technology with the continuous progress of science and technology, and it has been widely used in the ore prospecting, especially the uranium ore, which is an important strategic resource for the development of our country's nuclear industry. In recent years, 3D digital modeling technology has become a mainstream method in the geological industry with the rapid development of prospecting and prediction methods, and it plays a huge role in prospecting and prediction research for uranium deposits. In order to strengthen the prospecting prediction research of uranium deposits in the Xiangshan uranium ore field, a three-dimensional digital modeling study was carried out in this paper. Based on previous research of the metallogenic geological background, ore deposit characteristics and metallogenic regularity of the Julong'an uranium deposit in Xiangshan area, Jiangxi Province, a semi-automatic 3D digital and information modeling software, SKUA-GOCAD, was used to build topographic surface, structure stratigraphy and ore body models of the Julong'an uranium deposit in this paper. It can analyze the spatial distribution and geological morphological characteristics of each geological body in the study area using these digital and information models intuitively. Together with metallogenic characteristics, the metallogenic prospective area was divided using the 3D digital geological prediction model, and it showed that the prospecting potential for the Julong'an uranium mining area was great. From this research we can draw a conclusion that it has an obvious ore-controlling effect for the stratigraphy, structure and abrupt changing zone of interfaces of different formations. Meanwhile, the intersection region with the interface between the rock formations, the abrupt changing zone of the interface between different formations, and the intersection region of three interfaces are the favorable metallogenic areas. This research not only provided important prospecting ideas for the subsequent mineral exploration of uranium deposits, but also was beneficial to the next stage of ore prediction research in the Xiangshan area.

The construction industry is key to Thailand’s economy, which is growing consistently with domestic and international trends. Its projected growth is 3.0–4.0% annually from 2024 to 2026, consistent with overall investment trends. However, the recent Workers’ Compensation Fund data shows that construction consistently leads to occupational accidents, causing significant losses. From 2019 to 2023, residential construction accounted for 3.50% and nonresidential for 2.66% of annual occupational injuries, highlighting ongoing safety challenges. Therefore, the study focuses on the effectiveness of digital 2D and 3D modelling, including Building Information Modeling, in improving safety protocols and reducing workplace accidents. The study uses a quantitative approach to evaluate how digital 2D and 3D modelling tools affect work method development, risk assessments, safety awareness and compliance oversight. The results demonstrate a significant positive correlation between the use of digital models and enhanced safety performance indicators, such as reduced accident rates and increased client satisfaction. The most notable improvements occurred in work method formulation and risk assessment, where digital 2D and 3D modelling provide detailed visualizations that help identify potential hazards and plan safe construction practices.

IntroductionFor medical and allied health students, knowledge of anatomical variation is important as it may influence physical examination, diagnosis and treatment of patients. Recent studies indicate anatomical variation should be conceptually integrated early into the anatomy curriculum prior to the discipline specific variations taught in surgical and radiological postgraduate training programs. For academic institutions with limited access to cadaveric dissection and anatomy museums, the opportunity for students to appreciate the range of normality in anatomical structures is diminished. Thus, the purpose of this study was to demonstrate how 3D models of anatomical variations may be used to assess structure, function and spatial relationships by incorporating the concept of anatomical variations into assessment paradigms.MethodsTwo 3D digital models depicting upper limb muscular variations, and a 3D teratological model were evaluated by undergraduate kinesiology (KIN) (n = 30), and graduate clinical anatomy (CA) (n = 10) students. The study protocol consisted of the following instruments introduced in sequence: (1) 30‐question Spatial Ability Test (SAT), (2) 16‐question baseline upper limb anatomy test, (3) 13‐question multiple choice quiz based on the displayed 3D models, and (4) Student perception survey (5‐point Likert scale). Based on SAT scores, a median split was used stratify the students into high (KIN: 15, CA: 5) and low spatial ability (KIN: 15, CA: 5). All data are presented as Mean ± SD.ResultsBoth student groups scored similarly on the baseline anatomy knowledge test (KIN: 71 ± 17 %, CA: 71 ± 12%). The mean 3D model quiz scores for KIN students of high spatial ability were 72 ± 16% compared to those of lower spatial ability, 68 ± 14%. The 3D model quiz scores for CA students of high spatial ability were 88 ± 12% compared to CA students of lower spatial ability, 77 ± 15%. The models were perceived as useful in assessing spatial relationships (KIN: 4.4 ± 0.8, CA: 4.9 ± 0.3) and clinical concepts (KIN: 4.0 ± 0.9 CA: 3.9 ± 0.3). Student perceptions were positive for integrating the 3D models into lecture, or laboratory discussions, but KIN students were relatively neutral (3.2 ± 1.2) compared to CA students (3.9 ± 0.3) in their integrated use in bell‐ringer style laboratory assessments. The students expressed interest for a database of explorable 3D models of anatomical variations.ConclusionIntegration of the 3D variant models into anatomy curricula could be a useful means in assessing fundamental anatomical concepts, while demonstrating how deviations in structure can affect normal function. For institutions with computer access but limited cadaveric resources, the 3D models could be powerful supplementary teaching and assessment tools for anatomy students of all education levels and spatial abilities. Furthermore, development of a database of explorable anatomical variations for teaching and learning purposes would be valuable for allied health and medical programs in search of integrating variant anatomy into their anatomy curricula.Support or Funding InformationSupported by: American Association of Anatomists (AAA) Education Research Scholarship; Natural Sciences and Engineering Research Council of Canada (NSERC)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Assessment of Anomalous Coronary Arteries by Imagers and Surgeons: Comparison of Imaging Modalities