3D Planning Research Articles

Sagittal Discrepancies of Intraoperative Results between 2D and 3D Planning in Orthognathic Surgery: A Series of 44 Cases

Pre-surgical planning in orthognathic surgery is a process of vital importance for obtaining satisfactory results for both the clinician and the patient. There are different planning methods, among which 3D software is one of the most important. These allow precise observation of the movements of bone and soft tissue structures, which until recently could not be predicted. Despite its advantages, many specialists continue to plan using the 2D method. The aim of this paper is to present the discrepancies between 2D and 3D preoperative planning and the intraoperative results of 44 patients undergoing bimaxillary orthognathic surgery and, together with this, to expose the variables that possibly influence the occurrence of these differences.

Customized Genioplasty and Advantages of 3D Virtual Planning: An Updated Literature Review.

Genioplasty is a surgical technique that modifies the projection of the chin in three dimensions to achieve symmetry and facial harmonization. Virtual 3D planning is increasingly used, supplanting the conventional surgical technique due to the precise and predictable results obtained.The definition of the objective of the study was first carried out using the PICO (Patient, Intervention, Comparison, Outcome) question method. Posteriorly, an updated literature review was carried out in the "PubMed" database using the keywords "Genioplasty and Virtual 3D Planning," obtaining 11 articles for the study with the objective of defining the advantages and disadvantages of performing a virtually planned genioplasty, comparing it with the conventional technique.In the results, it is observed that virtually planned genioplasty presents greater precision, a reduction in surgical time, and a lower rate of complications than the conventional technique. Virtual planning using computer-aided design/computer-aided manufacturing technology presents good reproducibility in the patient with <2 mm variations between what was planned and what was obtained postoperatively, with statistically significant results (p < 0.001).In conclusion, virtually planned genioplasty with customized cutting guides and osteosynthesis plates achieves very precise surgery results with good reproducibility, reducing surgical time, intraoperative complications, and the difficulty of the surgical technique.

A new path planning strategy driven by geometric features and tensile properties for 3D printing of continuous fiber reinforced thermoplastic composites

Three-dimensional (3D) printing technology for continuous fiber reinforced thermoplastic composites (C-FRTP), capable of rapid manufacturing of lightweight components with intricate geometric features, has emerged as one of the most promising technologies in the field of advanced composite manufacturing. Path planning is a crucial step for determining the fabrication quality of C-FRTP components. This study proposed a new 3D printing path planning strategy driven by the geometric features and tensile properties of C-FRTP components. The strategy employed the properties of the Euler graph to generate the continuous full-field filling paths, ensuring the geometric features of the target components. The intersections were scattered along the printing path to enhance the tensile strength. The feasibility and advantages of the new path planning strategy were validated by comparative experiments with different printing paths. The results indicated that the new strategy not only achieved the geometric features of the target components but significantly enhanced their tensile strength. Using the printing path generated by the new path planning strategy, the tensile strength of specimens featuring mounting holes reached 349.4 MPa, which was only about 4.1 % lower than the tensile strength of continuous fibers at straight paths. Compared to the existing contour-parallel path, the new strategy in this work improved the tensile properties by about 40.9 %. The new path planning strategy proposed in this study shows great potential to design and fabricate C-FRTP components with enhanced mechanical properties for practical applications.

Passive fit and time efficiency for prefabricated versus conventionally constructed cobalt chromium CAD\\CAM 3-unit implant supported frameworks in free end saddle models: a pilot invitro study

BackgroundThe passive fit of 3-unit implant supported prefabricated metal screw-retained prosthesis before implant placement might be difficult. Hence, we aim to evaluate the passive fit and time efficiency of CAD/CAM 3-unit implant supported fixed prostheses that were constructed based on virtual versus those based on actual implant positions in Kennedy Class I models.MethodsA sample of 5 Kennedy class I models with thin wiry ridges were restored by 20 frameworks bilaterally, 10 based on actual (group A) and 10 based on virtual (group V) implant positions. The models were imaged using cone beam computed tomography and scanned using an intraoral scanner. The STL (Standard Tessellation Language files) and the DICOM (Digital Imaging and Communications in Medicine) files were registered on a 3D planning software. A CAD/CAM surgical guide was planned, resin printed and used for installing 6 implants bilaterally. In group V, the framework was designed based on the virtual scan bodies and virtual multi-unit abutments, while in group A intra-oral scanning of the model after attaching the scan bodies was necessary. Frameworks of both groups were milled and tested for passive fit using 8 clinical tests. McNemar and Wilcoxon signed rank tests were used to study the effect of the group on passive fit and time efficiency, respectively. The significance level was set at P ≤ 0.05.ResultsNo statistically significant difference was found between group V and group A frameworks regarding passive fit (p-value = 1, OR = 0.5) and time efficiency (P = 0.179, Effect size = 0.948).ConclusionWithin the limitations of this study, it can be concluded that in free end saddle cases, prefabricated CAD\\CAM 3-unit implant-supported cobalt chromium screw retained prostheses can achieve an adequate passive fit. However, their fit might be negatively affected in thin ridges and they might require some adjustments.

Optimizing range of motion in reverse shoulder arthroplasty.

Optimal glenoid positioning in reverse shoulder arthroplasty (RSA) is crucial to provide impingement-free range of motion (ROM). Lateralization and inclination correction are not yet systematically used. Using planning software, we simulated the most used glenoid implant positions. The primary goal was to determine the configuration that delivers the best theoretical impingement-free ROM. With the use of a 3D planning software (Blueprint) for RSA, 41 shoulders in 41 consecutive patients (17 males and 24 females; means age 73 years (SD 7)) undergoing RSA were planned. For the same anteroposterior positioning and retroversion of the glenoid implant, four different glenoid baseplate configurations were used on each shoulder to compare ROM: 1) no correction of the RSA angle and no lateralization (C-L-); 2) correction of the RSA angle with medialization by inferior reaming (C+M+); 3) correction of the RSA angle without lateralization by superior compensation (C+L-); and 4) correction of the RSA angle and additional lateralization (C+L+). The same humeral inlay implant and positioning were used on the humeral side for the four different glenoid configurations with a 3 mm symmetric 135° inclined polyethylene liner. The configuration with lateralization and correction of the RSA angle (C+L+) led to better ROM in flexion, extension, adduction, and external rotation (p ≤ 0.001). Only internal rotation was not significantly different between groups (p = 0.388). The configuration where correction of the inclination was done by medialization (C+M+) led to the worst ROM in adduction, extension, abduction, flexion, and external rotation of the shoulder. Our software study shows that, when using a 135° inlay reversed humeral implant, correcting glenoid inclination (RSA angle 0°) and lateralizing the glenoid component by using an angled bony or metallic augment of 8 to 10 mm provides optimal impingement-free ROM.

Three-Dimensional Holographic-Guided Robotic Lung Segmentectomy for Deep Pulmonary Nodules: Technique and Initial Results.

Background: Diagnosis and treatment of small and isolated lung nodules remain challenging issues. Purpose: The aim of this article is to report the technique of real-time navigation using holographic reconstruction technology combined with a robot assisted thoracic surgery (RATS) platform for lung resection in patients withsmall deep nodules.Research Design: The pre-surgery 3D planning was based on the chest CT scan. The reconstruction was uploaded to a head-mounted display for real-time navigation during mini invasive robot assisted surgery performed with an open console platform. We evaluated this technique with the success rate of diagnosis, the operative time and the post-operative course.Study Sample: This technique was performed in 6 patients (4 female, mean age 65 years) to date.Results: The precision of the head-mounted display based localization system was effective in all cases without the need of open conversion. The mean diameter of the nodules was 8mm (6-9). The diagnosis was a lung cancer (n = 5) and tuberculoma (n = 1). The mean operative time was 125min (100-145). The mean hospital stay was 2.5days (1-3).Conclusions: In conclusion, the intraoperative navigation using the 3D holographic assistance was an helpful tool for mini invasive RATS lung segmentectomy without the need of preoperative localization.

Preoperative 3D Planning and Intraoperative Navigation in Robot-Assisted Laparoscopic Surgery for Complex Pheochromocytoma.

To evaluate the value of preoperative 3D planning and intraoperative navigation in robot-assisted laparoscopic surgery for complex pheochromocytoma. Observational study. Place and Duration of the Study: Department of Urology, The Affiliated Hospital of Hebei University, from July 2022 to July 2023. Sixty patients with complex pheochromocytoma were divided into the study group (n = 30) and the control group (n = 30) according to the treatment method. The study group was treated with robot-assisted laparoscopic surgery, with preoperative 3D printing-based planning, and intraoperative 3D navigation, and the control group underwent conventional retroperitoneal robot-assisted laparoscopic surgery. Surgical-related indicators and intraoperative and postoperative complication rates between the two groups were compared. The operation time, postoperative hospital stay, and drainage tube retention time in the study group were significantly shorter than in the control group (p <0.001), and the intraoperative blood loss in the study group was significantly less than in the control group (p <0.001). The study group exhibited a significantly lower incidence of intraoperative haemodynamic instability (HI), use of vasoactive drugs, and postoperative ICU transfer rate than the control group (p <0.05). The incidence of surgical complications in the study group was significantly lower than in the control group (p = 0.04). The non-recurrence rate in the study and control groups after 1-year follow-up was 96.7% and 90%, respectively (χ2= 2.77, p = 0.10). Robot-assisted surgery, performed through renal surface, has the advantages of less bleeding, shorter surgical time, faster recovery, fewer complications related to chromaffin cell inflammation and postoperative complications, and is safe and effective in treating complex pheochromocytoma. 3D planning and navigation, Robot-assisted surgery, Complex pheochromocytoma.

3D Surgery Planning and Smile Arc Protection

3D Surgery Planning and Smile Arc Protection

Asymmetric Network Combining CNN and Transformer for Building Extraction from Remote Sensing Images.

The accurate extraction of buildings from remote sensing images is crucial in fields such as 3D urban planning, disaster detection, and military reconnaissance. In recent years, models based on Transformer have performed well in global information processing and contextual relationship modeling, but suffer from high computational costs and insufficient ability to capture local information. In contrast, convolutional neural networks (CNNs) are very effective in extracting local features, but have a limited ability to process global information. In this paper, an asymmetric network (CTANet), which combines the advantages of CNN and Transformer, is proposed to achieve efficient extraction of buildings. Specifically, CTANet employs ConvNeXt as an encoder to extract features and combines it with an efficient bilateral hybrid attention transformer (BHAFormer) which is designed as a decoder. The BHAFormer establishes global dependencies from both texture edge features and background information perspectives to extract buildings more accurately while maintaining a low computational cost. Additionally, the multiscale mixed attention mechanism module (MSM-AMM) is introduced to learn the multiscale semantic information and channel representations of the encoder features to reduce noise interference and compensate for the loss of information in the downsampling process. Experimental results show that the proposed model achieves the best F1-score (86.7%, 95.74%, and 90.52%) and IoU (76.52%, 91.84%, and 82.68%) compared to other state-of-the-art methods on the Massachusetts building dataset, the WHU building dataset, and the Inria aerial image labeling dataset.

Three-dimensional secondary reconstruction of mistreated zygomatic fractures using patient specific surgical guides and implants.

The zygomatic bone has a great impact on the anterior and lateral projection of the midface as well as the proper position of the globe. Primary alignment of zygomatic fractures is very important as secondary reconstruction is far more challenging. Treatment of misaligned zygoma requires refracturing of the bone to allow for repositioning. Due to the great impact of the zygoma on the projection of the midface, a precise 3D realignment is of great importance. Technology nowadays develops rapidly and allows for superior results in many surgical fields. The use of patient specific surgical guides and fixation plates is becoming more abundant. Using 3D segmentation and design software, we developed a sequence for using 3D planning and printing both for the refracturing stage, avoiding a coronal approach, and for precise repositioning and fixation of the zygoma in the new position. The method is described as well as a unique advanced 3D analysis, allowing for objectively assessing the results. Two cases are presented, including the design and post operative changes. Pre-op, planned and final positions were compared and showed exceptional accuracy allowing for the elimination of human errors which are common in a 3D sensitive procedure such as refracturing of the zygoma. This method can easily be applied to other secondary reconstruction procedures requiring realignment.

Geological factors in the sustainable management of mine water heating, cooling and thermal storage resources in the UK

Re-use of the UK's coal mine water heating, cooling and thermal storage resource is increasing in scale and the number of schemes. The upward trajectory requires 3D planning, regulation and licensing to manage sustainable deployment. We review geological factors controlling thermal and flow processes in the anthropogenically-altered subsurface, critical for resource management with multiple users of the same space. Potential interactions of mine water geothermal schemes with the wider environment are also summarized, leading towards concepts of 3D mine water thermal blocks, protection zones, or management strategies integrating heating, cooling and storage demands. Factors such as the magnitude, extent and timescale of thermal processes to underpin management approaches are poorly quantified by data measured at-scale under varying pumping rates and thermal loads. We demonstrate early insights of how two infrastructures, the UK Geoenergy Observatory in Glasgow and the Coal Authority's Mine Water Heat Living Lab in Gateshead, can measure and monitor heat-flow processes in real world settings to provide an evidence base. For example, a thermal storage test at Glasgow showed rapid temperature changes in the rock and mine workings at the re-injection borehole and indicated an influence of lithologically-controlled transmissivity and thermal conductivity on temperature dissipation and recovery.

The 3D plan analysis under progressive collapse for RC buildings through demand capacity ratio (DC) for three levels of damage

The progressive collapse presents a sudden load may cause initial failure in local parts at the frame which could lead to sequence reactions in the elements of the structure. A building of seven storeys was chosen to designed under gravity load according ACI 318 Code. This building is analyzed under progressive collapse condition for two columns damage cases; edge damage, corner damage. The building needs to be loaded as specified according (GSA) General Services Administration requirements through linear static analysis. The results of linear analysis show the variation in ((DC)) demand capacity ratio for the columns. The aspects of damage action in this study regarding section size and damage cases with 100% damage column loss (full damage), 60% damage (0.6 section size), 80% damage (0.8 section size). A GSA guideline to typical building with (DC) values bigger than 1.5 refer to critical potential damage conditions at the columns of the frame. It can be seen of the results the effect of size reduction for the building. This effect is clear to be decreased along distance from any plan. The((DC)) for columns which exceeded 1.5 value which show risky damage condition could actually happened that present serious threat possibility specially for nominated columns C22, C29 and C23 at plans A and B which show middle columns at lower position of the building.

Implantation of Reverse Shoulder Endoprothesis Using Navigation.

The implantation of a reverse shoulder arthroplasty (RSA) is a proven method for pain relief and improvement in shoulder function. Results vary, depending on the patient's age, the severity of the disease, and the experience of the surgeon. Indications for RSA are diverse, ranging from rotator cuff arthropathy to fractures. Recent studies show improved survival rates and reduced complications after primary implantation. Preoperative planning using 3D-CT or MRI is considered to be the gold standard. Patient-specific instruments (PSI) have been introduced, but are associated with costs and waiting times. Navigation with augmented reality (AR) provides a more efficient alternative. The intraoperative transfer of the plan to the patient is carried out via AR glasses, allowing real-time information without having to divert the surgeon's attention from the surgical site. This optimises the workflow and potentially yields more precise implantation results. In summary, the combination of 3D planning, navigation, and AR offers a promising method for precise and efficient RSA-implantations. Nevertheless, long-term results and functional scores are not yet available.

3D printing indoor evacuation plans for visually impaired people

3D printing indoor evacuation plans for visually impaired people

The Emerging Role of Three-dimensional Technologies in Orthoplastic Surgery.

Three-dimensional (3D) planning and manufacturing technologies have become integral to head and neck reconstruction following tumor resection. These technologies facilitate the prototyping of patient-specific solutions in both digital and physical form. Three-dimensional tumor models and cutting guides help conceptualize and verify the surgical approach, as well as serve as a blueprint for reconstruction. Computer-aided renderings have been shown to add precision to bony contouring to achieve functional and aesthetic goals following tumor resection, such as in mastication, oral competence, speech, and symmetric facial aesthetics. Three-dimensional technologies have also been introduced in orthopedic oncology, making limb-salvage surgery the mainstay of treatment in cases where amputation was historically required. The advent of customized 3D cutting guides and plates allows surgeons to spare surrounding healthy tissue, markedly enhancing postoperative quality of life and significantly reducing associated morbidities. Borrowing from these applications of 3D planning and modeling, our institution has recently implemented these technologies for the reconstructive planning of soft tissue defects following sarcoma resection. Here we present a series of cases that demonstrate the workflow and clinical outcomes associated with the utilization of 3D planning techniques in orthoplastic surgery.

Evaluation of Two Clinical Stem-Fit Philosophies Within the Femoral Canal Using a Preoperative Planning Tool: Could a Hybrid Approach Be Best?

BackgroundTotal hip arthroplasty (THA) has transformed patient lives, yet evolving expectations and the number of postoperative foot angle changes have underscored the need for precise component positioning. The objective of this study was to use 3-dimensional (3D) preoperative planning to evaluate stem alignment and orientation for three THA systems using two different stem-fit algorithms. It was hypothesized that the different stem alignments would yield similar changes in stem orientation and placement within the canal for all 3 systems. MethodsThis study introduced a novel 3D preoperative planning tool, comparing two different surgical stem-fit philosophies within the canal: “canal fit” (CF) and “anatomical fit” (AF). We virtually implanted 10 subjects with three different THA implant systems using both philosophies, evaluating 60 total fits within the canals. The CF philosophy aimed to minimize cortical bone removal. In contrast, the AF philosophy prioritized aligning the implanted head with the anatomical head center. ResultsDetailed analyses revealed that AF led to fixation occurring mainly on the medial aspect of the stem, while CF exhibited a more even distribution between medial and lateral sides. The AF philosophy achieved significantly closer placement of the implanted head to the anatomical center (2.0 to 2.1 mm) compared to the CF philosophy (3.0 to 6.0 mm) (P < 0.01). The AF resulted in neutral stem orientation (0°) across all stems, whereas the CF exhibited greater malrotation (2.0 to 7.0°) (P < 0.02). The AF required more bone removal (0.13 to 0.46 cm³) than the CF (0.02 to 0.06 cm³) (P < 0.01). ConclusionsThe findings underscore the importance of 3D planning, emphasizing its potential to improve stem version alignment in THA. The results from this study may advocate 3D preoperative planning with robotic surgery to plan stem placement within the canal while maintaining anatomical femoral head restoration.

Virtual surgical planning in orthognathic surgery: A prospective evaluation of postoperative accuracy

ObjectivesThe development of 3D computer-assisted technologies over the past years has led to vast improvements in orthognathic surgery. The aim of the present study was to evaluate differences in maxillary position between 3D virtual surgical planning (VSP) and surgical results. Materials and methodsWe assessed data from 25 patients who underwent bimaxillary non-segmented orthognathic surgery with 3D VSP. Each patient underwent a postoperative CT scan within 40 days after surgery. We compared the STL (Standard Triangulation Language) file from the VSP with that obtained from the postoperative CT. ResultsAccording to our comparative analysis, the postoperative and VSP 3D models did not statistically differ. The Lin concordance correlation coefficient was always >0.95 for each landmark, but in 21 patients (84 % of the sample) we identified at least one point with a difference of more than 1.5 mm between the postoperative and VSP 3D model on at least one axis. The most frequently observed differences corresponded to sagittal translation and pitch rotation. ConclusionsAn intraoperative clinical and aesthetic evaluation of the consequences of bone movements on patient face is strongly recommended, also when we use VSP because we may have clinically significant differences from the planning.

Accuracy of Implant Placement Based on Three-Dimensional Preoperative Planning in Total Elbow Arthroplasty.

Background: Accurate implant placement in the optimal position is important to obtain favourable clinical outcomes and prevent complications in total joint arthroplasty. We aimed to assess the accuracy of implant placement based on three-dimensional (3D) preoperative planning for unlinked total elbow arthroplasty (TEA) and to clarify the effect of implant placement on clinical outcomes. Methods: This study included 20 patients (22 elbows, 17 with rheumatoid arthritis and 5 with osteoarthritis, with a mean follow-up period of 47 months) who underwent TEA with an unlinked-type implant after computed tomography (CT)-based 3D preoperative planning. Implant placement was planned preoperatively and several parameters were set to reflect it intraoperatively. TEA was performed based on the plan, and postoperative CT was conducted to evaluate differences in implant placement by comparing the preoperative plan and postoperative implant placement. Furthermore, we evaluated the relationship between implant placement differences and postoperative clinical outcomes, including range of motion, Visual Analogue Scale, Mayo Elbow Performance Score 1 year after surgery and complications at the last follow-up. Results: The mean absolute translation was within 2 mm, the mean absolute tilt was within 4°, the mean absolute rotation of the humeral component was within 4° and the mean absolute rotation of the ulnar component was 10.2° ± 6.8°. In the ulnar components, 15/22 (68%) cases were externally rotated, and the mean external rotation was 7.1° ± 10.2°. We defined the absolute ulnar component's rotational difference of more than 10° as a 'malrotation' group (n = 8) and 10° or less as a 'control' group (n = 14). We compared the clinical outcomes between both groups, however, no significant differences were observed in clinical outcomes and complications. Conclusions: We observed notable malrotation in the postoperative positioning of the ulnar component. Intraoperative support devices may be necessary to accurately reproduce the preoperative plan in the surgical field. Level of Evidence: Level IV (Therapeutic).

A comparison between 3D printed models and standard 2D planning in the use of metal block augments in revision knee arthroplasty.

The study focused on the ability to predict the need and size of femoral and tibial augmentation using standard two-dimensional (2D) templates and models created with three-dimensional (3D) printing in surgical planning. This observational cohort study included 28 consecutive patients (22 females, 6 males; mean age: 71±7.3 years; range, 54 to 82 years) with periprosthetic joint infection recruited between March 2021 and September 2023 undergoing revision total knee arthroplasty revision (TKA). Standard planning was made using calibrated X-ray images. The 3D planning started with computed tomography scans to generate a 3D template of the distal femur and proximal tibia. The model was exported to a 3D printer to produce a patient-specific phantom. The surgery was then simulated on the 3D phantom using revision knee arthroplasty instrumentation to evaluate the appropriate augmentation to use until a correct alignment was obtained. Three-dimensional planning predicted the need for femoral and tibial augments in 22 (78.6%) cases at both the tibial and femoral components, while 2D planning correctly predicted the need for augmentation in 17 (60.7%) for the tibial side and 18 (64.3%) for the femoral side. The Cohen's kappa demonstrated a significant agreement between the 3D planning for the femoral metal block and the intraoperative requirement (kappa=0.553), whereas 2D planning showed only nonsignificant poor agreement (kappa=0.083). In contrast, the agreement between 2D or 3D preoperative planning for tibial augment and the intraoperative requirement was nonsignificant (kappa=0.130 and kappa=0.158, respectively). On the femoral side, 2D planning showed only a fair nonsignificant correlation (r=0.35, p=0.069), whereas 3D planning exhibited substantial agreement with the actual thickness of the implanted augment (r=0.65, p<0.001). On the tibial side, 3D and 2D planning showed substantial agreement with the actual size of implanted augments (3D planning, r=0.73, p<0.001; 2D planning, r=0.69, p<0.001). Prediction based on 3D computed tomography segmentation showed significant agreement with the intraoperative need for augmentations in revision TKA. The results suggest that planning with 3D printed models represents a stronger aid in this kind of surgery rather than standard 2D planning, providing greater accuracy in the prediction of the required augmentation in revision TKA.

Three-Dimensional Coverage Path Planning for Cooperative Autonomous Underwater Vehicles: A Swarm Migration Genetic Algorithm Approach

Cooperative marine exploration tasks involving multiple autonomous underwater vehicles (AUVs) present a complex 3D coverage path planning challenge that has not been fully addressed. To tackle this, we employ an auto-growth strategy to generate interconnected paths, ensuring simultaneous satisfaction of the obstacle avoidance and space coverage requirements. Our approach introduces a novel genetic algorithm designed to achieve equivalent and energy-efficient path allocation among AUVs. The core idea involves defining competing gene swarms to facilitate path migration, corresponding to path allocation actions among AUVs. The fitness function incorporates models for both energy consumption and optimal path connections, resulting in iterations that lead to optimal path assignment among AUVs. This framework for multi-AUV coverage path planning eliminates the need for pre-division of the working space and has proven effective in 3D underwater environments. Numerous experiments validate the proposed method, showcasing its comprehensive advantages in achieving equitable path allocation, minimizing overall energy consumption, and ensuring high computational efficiency. These benefits contribute to the success of multi-AUV cooperation in deep-sea information collection and environmental surveillance.