3D Group Research Articles

[Translated article] Can 3D-printed patient-specific instruments improve local control and overall survival in pelvic sarcoma? A clinical validation study

Background and objectives 3D-printed patient-specific instruments (PSIs), also known as 3D guides, have been shown to improve accuracy in resection of pelvic tumors in cadaver studies and achieve better surgical margins in vivo. This study evaluates the clinical impact of 3D-printed guides on medium-term local and distant disease control, as well as disease-free and overall survival in patients.Material and methods A cohort study included 25 patients with primary pelvic or sacral sarcomas: 10 in the 3D group and 15 in the control group, with a median follow-up of 47 months. Demographic and clinical data, including tumor histology, stage, resection technique, associated reconstruction, adjuvant therapies, and complications, were evaluated. Surgical margins (free, marginal, and contaminated) and relapse-free and overall survival curves were analyzed.Results The 3D group achieved a higher rate of free margins (80% vs 66.7%, p = 0.345). Local recurrence (50% vs 60%, P=.244) and distant disease relapse (20% vs 47%, p = 0.132) rates were lower in the 3D group. At the end of the follow-up, the 3D group had a higher overall survival rate (60% vs 40%, p = 0.327). The complication rate was similar in both groups, with a deep infection rate of 40%.Conclusions The use of 3D guides in resecting primary pelvic tumors not only achieves a higher rate of free margins compared to conventional techniques but also shows a trend towards higher local, distant, and overall disease-free survival. Further studies with larger sample sizes and higher levels of evidence are necessary to validate these clinical trends.

Osteoinductively Functionalized 3D-Printed Scaffold for Vertical Bone Augmentation in Beagle Dogs.

To evaluate the efficacy of 3D-printed scaffolds that were osteoinductively functionalized with a bone morphogenetic protein 2 (BMP-2)-incorporated biomimetic calcium phosphate particles (BMP-2-inc. BpNcCaP)/hyaluronic acid (HA) composite gel in vertical bone augmentation in beagle dogs. Four Beagle dogs were used in this study. Three months after the extraction of 1st, 2nd, 3rd, and 4th premolars at both sides of the lower jaws of Beagle dogs, one or two critical-size vertical bone defects (4 mm vertical bone defect without buccal and lingual bone) on each sidewere surgically created. The defects were randomly subjected to the following groups: (1) Control (without bone-defect-filling materials); (2) 3D scaffold; (3) BMP2-inc. BpNcCaP/HA-functionalized 3D scaffold. Six weeks post-surgery, samples were harvested and subjected to micro-CT and histomorphometric analyses. The struts of the BMP2-inc. BpNcCaP/HA-func. 3D scaffold were covered by a thick layer of cemented irregular particles with an average pore size at 327 ± 27 μm. The BpNcCaP/HA-func. 3D scaffold group bore significantly higher bone volume, bone volume fraction, trabecular number, trabecular thickness, bone mineral density, connectivity density, and bone volumes in three directions (mesiodistal, buccolingual, and apicocoronal) when compared with the groups of Control and 3D scaffold. Moreover, the BMP2-inc. BpNcCaP/HA-func. 3D scaffold group bore significantly lower trabecular separation and exhibited significantly higher bone-to-scaffold contact percentage and newly formed bone area percentage within pores in comparison with 3D scaffold. BMP2-inc. BpNcCaP/HA-func. 3D scaffold dramatically enhanced vertical alveolar bone augmentation, which suggests a promising application potential of BMP2-inc. BpNcCaP/HA-func. 3D scaffold in dental clinic.

A supramodal thorough account of the Molyneux question

In this paper, we want to tackle the Molyneux question thoroughly, by addressing it in terms of both ordinary perception and pictorial perception: if a congenitally blind person recovered sight, could she recognize visually the 3D shapes she already recognized tactilely, both when such shapes are given to her directly and when they are given to her pictorially, i.e., as depicted shapes? We want to claim that empirical evidence suggests that the question can be positively answered in both cases. For in the first case, such evidence shows that perception of 3D shapes is supramodal; namely, it can be equivalently achieved in different sense modalities, notably touch and vision, independently of the sensory input such shapes are accessed. While in the second case, such evidence shows that one can satisfy both in vision and in touch the condition for depicted shapes, which are typically not where the perceiver is, to be grasped by that perceiver in a picture’s subject, i.e., what the picture presents. This condition states that the picture’s vehicle, i.e., the typically 2D physical basis of a picture, is enriched by adding to its properties the 3D grouping properties that allow for a figure/ground segmentation to be performed in that vehicle’s elements.

3D vs. 2D-4 K: Performance and self-perception of laparoscopic novices in a randomized prospective teaching intervention using standard tasks and box trainers

ObjectiveThe use of three-dimensional (3D) laparoscopy in surgical practice and training has been an area of research and discussion. Studies have suggested that 3D vision can improve speed and precision compared to traditional two-dimensional (2D) displays, while other authors found no benefits on the learning curves of laparoscopic novices. Modern two-dimensional laparoscopy with a resolution of 3840 × 2160 pixels (2D-4 K) seems to improve laparoscopic view and helps learners orient without stereopsis. However, evidence comparing these systems for laparoscopic training is limited. Therefore, the impact of viewing mode (2D-4 K vs. 3D) on learning and task proficiency remains unclear.DesignWe performed a two-hour teaching intervention on basic laparoscopic skills for novices. In this parallel group randomized study, we randomly assigned learners to 2D-4 K or 3D teaching and performed tasks of increasing difficulty and complexity using standard laparoscopy box trainers. Before the last and most challenging task, learners had to crossover to the other laparoscopy setup. Our hypothesis was that learners would be faster and more precise when using a 3D setup. The primary endpoint was task proficiency measured by speed and failure rate. Secondary outcomes were performance using the viewing mode of the other group without familiarization, self-perception, and career aspirations before and after the teaching intervention, expressed on a Likert scale.SettingThe study was performed by the Department of General, Visceral and Thoracic Surgery at the German Armed Forces Hospital Ulm, which is an academic teaching hospital of the University of Ulm.ParticipantsThirty-eight laparoscopic novices, including medical students and junior residents, participated voluntarily in this teaching intervention. Group allocation was performed via the virtual coin flip method. Apparently, participants and tutors were not blinded to group assignment. No formal approval by the ethics committee was needed for this noninvasive study in compliance with the World Medical Association Declaration of Helsinki as discussed with the ethics committee of the University of Ulm.ResultsThirty-eight laparoscopy novices were randomized in the study. The 3D group (n = 19) was significantly faster than the 2D-4 K group (n = 19) (p = .008) in a standard box trainer model, with 134.45 ± 41.45 s vs. 174.99 ± 54.03 s for task 1 and 195.97 ± 49.78 s vs. 276.56 ± 139.20 s for task 2, and the effect was consistent throughout the learning curve. The failure rate was not significantly affected by the viewing mode. After crossover to the other laparoscopy system, precision and time were not significantly different between the groups. Learners rated the difficulty of laparoscopy lower on a Likert scale after having two hours of basic laparoscopy training. The study was funded by the hospital’s teaching budget.ConclusionsLaparoscopic novices can benefit from a 3D laparoscopy training setup. Exclusive 3D training prior to a complex task on a 2D-4 K setup does not negatively affect the learner’s performance.

Three-dimensional-printed guide plate for direct percutaneous pedicle screw implantation in minimally invasive transforaminal lumbar interbody fusion surgery: a retrospective study of 162 patients

BackgroundThis study aimed to investigate the impact of three-dimensional (3D)-printed guide plate-assisted percutaneous pedicle screw implantation on minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) surgery.MethodsOverall, 162 patients who underwent MIS-TLIF at Tai’an City Central Hospital were retrospectively reviewed. The studied variables included operative time, volume of intraoperative blood loss, fluoroscopy time, postoperative drainage volume, visual analogue scale (VAS) score, Oswestry disability Index (ODI) score (preoperatively and at 2 weeks, 3 months, 6 months, and 12 months after surgery), and intervertebral fusion rate at 6 months after surgery.ResultsThe conventional group included 99 patients who underwent a conventional procedure, while the 3D printing group included 63 patients who underwent 3D-printed guide plate-assisted percutaneous pedicle screw implantation. The conventional group required more times of positioning needle punctures than the 3D printing group (22.2 ± 5.9 vs. 16.1 ± 4.9). The operation and fluoroscopy time were also longer in the former group (183.5 ± 51.1 min vs. 148.8 ± 40.3 min and 30.2 ± 5.9 s vs. 24.1 ± 4.9 s, respectively). In 3D printing group, lower back pain VAS scores and ODI scores at 2 weeks and 3 months after surgery were observed. There were no significant differences in terms of the volumes of intraoperative blood loss; postoperative lower limb pain VAS scores; and interbody fusion rate (P > 0.05).ConclusionThe novel 3D-printed guide plate-assisted percutaneous pedicle screw implantation can achieve better amelioration of back pain and recovery of function. It also reduced the times of positioning needle puncture and fluoroscopy time during percutaneous screw placement surgery and reduced the duration of surgery.

Performance of game sessions in VR vs standard 2D monitor environment. an EEG study.

Nowadays studies using Virtual Reality (VR) are gaining high popularity due to VR being a better approximation of the ecological environment for visual experiments than standard 2D display settings. VR technology has been already applied in medicine in the therapy of mental disorders, neurorehabilitation, and neurofeedback. However, its effectiveness compared to the standard 2D procedure is still not fully documented and limited information about the neurophysiological underpinnings of VR is provided. In this study, we tested participants' performance during several sessions of the computer game in two different environments, VR vs. 2D monitor display. Participants performed three 25 min gaming sessions of adapted Delay Match-To-Sample task during EEG recording. The results showed that the VR group outperformed the 2D display group in the first session and then maintained its performance level throughout the remaining two sessions while the 2D group increased performance in each session eventually leveling up in the last one. Also group differences in the EEG activity were most profound only in the first session. In this session, the VR group was characterized by stronger and more synchronized neuronal activity, especially in delta, theta, and gamma bands. The VR group was less impacted by visual arousals as indicated by the theta/beta2 ratio in parietal electrodes.

Evaluating the impact of brachytherapy duration on therapeutic outcomes in patients with cervical cancer

The total duration of radiotherapy for patients with cervical cancer should be limited to 56 days to optimize treatment outcomes. This study aimed to statistically evaluate the effects of extended radiotherapy duration on survival and complications in 649 patients with cervical cancer treated with brachytherapy at our institution from 2014 to 2019. All patients had undergone intensity-modulated external beam radiation therapy, with 525 receiving two-dimensional (2D) brachytherapy and 124 receiving three-dimensional (3D) brachytherapy. Using the inverse probability of treatment weighting (IPTW) and propensity score matching (PSM), clinical data regarding treatment duration, survival outcomes, and complications were analyzed. PSM revealed that overall survival (OS) did not significantly differ between patients receiving prolonged treatment (>56 days) and those receiving treatment for a standard duration (<56 days) (P > 0.05). However, among patients who had received 2D brachytherapy, prolonged treatment correlated with increased recurrence and metastasis risks (P < 0.001); this trend was not evident in patients receiving 3D brachytherapy (P = 0.287). Higher FIGO stages were associated with worse OS and higher progression risks, which persisted post-IPTW adjustment. Extended radiotherapy duration was linked to a higher incidence of rectal and bladder reactions, particularly in the 2D group. Consequently, strictly controlling radiotherapy duration for patients receiving 2D brachytherapy is essential to reduce recurrence and metastasis risks. Close monitoring of rectal and bladder reactions is also recommended.

Utilizing 3D Model and Comparison Software Tools in Improving Assessment Methods: A Pilot Study

Purpose/Objectives: This manuscript investigates the effectiveness of computer-assisted design and manufacturing (CAD/CAM) technology in preclinical dental education. The COVID-19 pandemic created a need for remote teaching approaches. In preclinical fixed prosthodontics courses, traditional evaluation methods rely on faculty to visually grade laboratory projects utilizing rubrics and 2D images. Assessment and feedback vary amongst faculty, and faculty calibration has been inconsistent in reducing intra-and inter-rater variability. This study aimed to compare faculty assessment of student full coverage crown (FCC) preparations traditionally versus digitally through 3D model visual assessment and/or comparative analysis software reports. Methods: Eighteen UTHealth Houston School of Dentistry faculty participated, each randomly assigned into one of three assessment groups: traditional visual Group (TV), 3D Group (3D), and 3D visual assessment supplemented with comparative analysis software report (3D+) Group. Faculty graded the same eight lithium disilicate typodont preparations for all three assessment groups. Results: Survey results showed the ease of use and efficiency among the three assessment methods varied significantly. Grading scores revealed that axial wall reduction significantly differed among the three assessment methods. Conclusion: This study concludes that the combination of the two digital assessment methods can overcome the limitations of traditional evaluation methods and digital methods alone by providing objective feedback to students and enhancing their learning experience.

A novel 3D printed model for educating medical students on limb fractures: a randomized controlled preliminary study

BackgroundMedical education related to bone fracture must address numerous challenges including complex anatomical characteristics, diverse injury mechanisms, fracture typing, and treatment modalities. Our newly developed 3D printed model comprises components that may be combined or split to simulate various anatomical features, fracture types, and treatment modalities. This study aims to analyze the teaching utility of the new 3D-printed model compared with the traditional solid model.MethodsThis prospective study included 112 students randomly assigned to fracture-related education with a conventional model or the newly developed 3D-printed model. All students received 40 min of lecture, 20 min for femoral neck and 20 min for tibiofibular fractures, and a post-class quiz (10 min each) immediately followed. Scores on tests of fracture-related knowledge and user satisfaction were measured pre and post education for comparison.ResultsThe 3D printing group had an advantage in retention of anatomic knowledge, fracture typing and choice of treatment for the femoral neck fracture (P < 0.05). For the tibiofibular fracture the 3D printing group had an advantage in retention of anatomic knowledge and fracture complications (P < 0.05).Scores on the questionnaire survey also showed increased satisfaction in the 3D-printed model group(P < 0.05).ConclusionsThe proposed 3D-printed model can enhance the teaching effect significantly and has potential for widespread use in medical student education.

3D monitors improve performance on the HUGO™ RAS system: a randomised trial.

Robot-assisted surgery is used worldwide, allowing surgeons to perform complex surgeries with increased precision and flexibility. It offers technical benefits compared to traditional laparoscopic surgery due to its utilization of both 3D vision and articulated instruments. The objective was to investigate the isolated effect of 3D- versus 2D monitors when working with articulated instruments in robot-assisted surgery. Surgical novices (medical students, n = 31) were randomized to simulation-based training with either the 3D vision switched on or off. Both groups completed each of the four exercises six times over two sessions on the Medtronic Hugo™ RAS system simulator. The outcome was the simulator performance parameters and a visual discomfort questionnaire. For the efficiency parameters, we found that both groups improved over time (p < 0.001) and that the intervention group (3D) consistently outperformed the control (2D) group (p < 0.001). On the other hand, we didn't find any significant difference in the error metrics, such as drops (p-values between 0.07 and 0.57) and instrument collisions (p-values between 0.09 and 0.26). Regarding Visual Discomfort, it was significantly more difficult for the 3D group to focus (p = 0.001). 3D monitors for an open robotic console improve efficiency and speed compared to 2D monitors in a simulated setting when working with articulated instruments.

Comparison of three-dimensional vs. two-dimensional assisted thoracoscopy for recurrent laryngeal nerve lymph nodes dissection in esophagectomy: a retrospective study

BackgroundThis study aimed to explore the clinical value of 3D video-assisted thoracoscopic surgery in dissecting recurrent laryngeal nerve lymph nodes in patients undergoing minimally invasive esophagectomy.MethodsA retrospective cohort study was conducted on 205 patients, including 120 males, who underwent esophagectomy from May 2018 to May 2020 in the Department of Thoracic Surgery at the Affiliated Huai’an No.1 People’s Hospital of Nanjing Medical University. Perioperative parameters, including intraoperative blood loss, operation time, the number of dissected recurrent laryngeal nerve lymph nodes, the incidence and degree of postoperative recurrent laryngeal nerve injury, the volume of postoperative thoracic drainage, and postoperative complications, were compared between the 3D and 2D groups.ResultsThere were no significant differences in the preoperative baseline data between these two groups (P > 0.05). The number of dissected recurrent laryngeal nerve lymph nodes in the 3D group was significantly higher than in the 2D group (P < 0.05). The operation times were significantly shorter in the 3D group than in the 2D group (P < 0.05). The volume of thoracic drainage in the first 2 days was significantly less in the 3D group than in the 2D group (P < 0.05).ConclusionsCompared to the 2D system, the application of 3D video-assisted thoracoscopic surgery in minimally invasive esophagectomy can increase the number of dissected recurrent laryngeal nerve lymph nodes and ensure safety. Additionally, it can reduce the duration of the operation, decrease early postoperative thoracic drainage volume, and promote patient recovery.

The comparison of 2D and 3D systems in total laparoscopic hysterectomy: a systematic review and meta-analysis.

To evaluate the existing evidence regarding the comparison between 2 and 3D systems in Total Laparoscopic Hysterectomy (TLH) in terms of surgical outcomes. A systematic review of electronic databases, including PubMed/MEDLINE and Web of Science, was conducted to identify relevant studies comparing 2D and 3D systems in TLH. The search employed a combination of Medical Subject Headings (MeSH) terms and keywords related to the topic. Studies meeting predefined criteria were included, while case reports and studies not directly comparing 2D and 3D systems were excluded. Two independent reviewers evaluated study eligibility and performed quality assessment. The quantitative synthesis was conducted using meta-analysis techniques. A statistically significant longer operation time in the 2D group compared to the 3D group (7 studies, mean difference [MD]: 13.67, 95% confidence interval [CI] 9.35-18.00, I2 = 16%). However, no statistically significant differences were found between the groups in terms of vaginal cuff closure time (2 studies, MD: 3.22, CI -6.58-13.02, I2 = 96%), complication rate (7 studies, odds ratio [OD]: 1.74, CI 0.70-4.30, I2 = 0%), blood loss (3 studies, MD: 2.92, CI -15.44-21.28, I2 = 0%), and Hb drop (3 studies, MD: 0.17, CI -0.08-0.42, I2 = 1%). Our results revealed a significant difference favoring 3D systems in operation time, while clinical outcomes between the two systems were found to be comparable in TLH. However, further research, particularly prospective studies with larger cohorts and longer-term follow-up, along with economic analyses, is needed to provide clinicians and healthcare decision-makers with essential guidance for practice and resource allocation.

Monocular 3D Multi-Person Pose Estimation for On-Site Joint Flexion Assessment: A Case of Extreme Knee Flexion Detection.

Work-related musculoskeletal disorders (WMSDs) represent a significant health challenge for workers in construction environments, often arising from prolonged exposure to ergonomic risks associated with manual labor, awkward postures, and repetitive motions. These conditions not only lead to diminished worker productivity but also incur substantial economic costs for employers and healthcare systems alike. Thus, there is an urgent need for effective tools to assess and mitigate these ergonomic risks. This study proposes a novel monocular 3D multi-person pose estimation method designed to enhance ergonomic risk assessments in construction environments. Leveraging advanced computer vision and deep learning techniques, this approach accurately captures and analyzes the spatial dynamics of workers' postures, with a focus on detecting extreme knee flexion, a critical indicator of work-related musculoskeletal disorders (WMSDs). A pilot study conducted on an actual construction site demonstrated the method's feasibility and effectiveness, achieving an accurate detection rate for extreme flexion incidents that closely aligned with supervisory observations and worker self-reports. The proposed monocular approach enables universal applicability and enhances ergonomic analysis through 3D pose estimation and group pose recognition for timely interventions. Future efforts will focus on improving robustness and integration with health monitoring to reduce WMSDs and promote worker health.

Therapeutic effect of three-dimensional hanging drop cultured human umbilical cord mesenchymal stem cells on osteoarthritis in rabbits

BackgroundMesenchymal stem cells (MSCs) have shown a positive effect on Osteoarthritis (OA), but the efficacy is still not significant in clinical. Conventional two-dimensional (2D) monolayer culture method is prone to cause MSCs undergoing replication senescence, which may affect the functions of MSCs. Three-dimensional (3D) culture strategy can sustain cell proliferative capacity and multi-differentiation potential. This study aimed to investigate the therapeutic potential of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) cultured by 3D hanging drop method on OA.MethodshUC-MSCs were isolated from umbilical cord and cultured by 3D hanging drop method for 48 h. Scanning electron microscopy (SEM) was used to observe gross morphology 2D and 3D hUC-MSCs. Transcriptome comparison of gene expression differences between 2D and 3D hUC-MSCs. GO enrichment analysis, KEGG pathway enrichment analysis and GSEA enrichment analysis were used to analyze the impact of 3D hanging drop culture on the biological functions of hUC-MSCs. Female New Zealand rabbits (n = 12) were divided into 4 groups: Normal group, Model group, 2D hUC-MSCs treatment group and 3D hUC-MSCs treatment group. After 8 weeks, the gross and histological appearance of the cartilage was evaluated by safranin O-fast green staining and Mankin scoring system. The expression of type I collagen and type II collagen was detected by immunohistochemistry. The levels of IL-6, IL-7, TNFα, TGFβ1 and IL-10 in the knee joint fluid were tested by ELISA.Results3D hanging drop culture changed cell morphology but did not affect phenotype. The MSCs transcriptome profiles showed that 3D hanging drop culture method enhanced cell-cell contact, improved cell responsiveness to external stimuli and immunomodulatory function. The animal experiment results showed that hUC-MSCs could promote cartilage regeneration compared with Model group. 3D hUC-MSCs treatment group had a higher histological score and significantly increased type II collagen secretion. In addition, 3D hUC-MSCs treatment group increased the expression of anti-inflammatory factors TGFβ1 and IL-10.ConclusionThe above experimental results illustrated that 3D hanging drop culture method could enhance the therapeutic effect of hUC-MSCs, and showed a good clinical application prospect in the treatment of OA.

Clinical application of 3D-printed fusion cage implantation in treating cervical spondylotic myelopathy.

To investigate the clinical efficacy of 3D-printed fusion cage implantation in treating cervical spondylotic myelopathy. A retrospective analysis was performed on 52 patients with single-segment cervical spondylotic myelopathy who received anterior cervical discectomy and fusion in Affiliated Hospital of Beihua University from July 2019 to July 2022. They were divided into the 3D group and the control group. Afterward, the perioperative indicators were compared between the two groups. Meanwhile, the Japanese Orthopaedic Association (JOA) scores, Visual analogue scale (VAS) and neck disability index (NDI) were recorded pre-operation and one-year post-operation. Evaluate the fusion rate of two group of intervertebral fusion cages. The JOA score and NDI of the two groups of patients were significantly improved compared to pre-operation(P<0.05), and the JOA score, JOA score improvement rate, and NDI of the 3D group were better than the control group (P<0.05), the VAS scores were significantly improved compared to pre-operation(P<0.05), but there was no statistically significant difference between the groups (p >0.05). The intervertebral height, angle, and cervical Cobb angle of the two groups of patients were significantly improved compared to pre-operation (P<0.05), and the improvement of intervertebral height, angle, and cervical Cobb angle in the 3D group was better than the control group(P<0.05). The clinical efficacy of 3D printed intervertebral fusion cage placement in the treatment of cervical spondylotic myelopathy may be reliable, and it would be better than traditional intervertebral fusion cages in maintaining the height, angle, cervical Cobb angle, and fusion rate of the intervertebral space.

Analysis of the Clinical Value of Two-Dimensional Plus Four-Dimensional Ultrasound in the Diagnosis of Fetal Facial Anomalies

Objective: To explore and analyze the clinical value of two-dimensional plus four-dimensional ultrasound in diagnosing fetal facial anomalies. Methods: To review and analyze the basic data of 50 fetuses with facet anomalies delivered in Maternal and Child Health Hospital of Jiangyan District from January 2017 to January 2023, and to analyze and compare the two-dimensional (2D) diagnostic results of all the fetuses (2D group), and the combined 2D and four-dimensional (4D) diagnostic results (combined group). Results: Taking the delivery results as the gold standard, 39 fetuses with facial anomalies were diagnosed in the 2D group, and 48 fetuses with facial anomalies were diagnosed in the combined group, which showed that the diagnostic compliance rate of the 2D group was significantly lower than that of the combined group, and the difference of P &lt; 0.05 was statistically significant. The sensitivity and accuracy of the diagnostic efficiency of the combined group were significantly higher than that of the 2D group, and the difference was statistically significant at P &lt; 0.05; the specificity of the diagnostic efficiency of the combined group and the 2D group was compared, and the difference was not statistically significant at (P &gt; 0.05). Conclusion: 2D plus 4D ultrasounds are more accurate in diagnosing fetal facial anomalies, and the combined diagnosis is more clinically significant, so it is recommended to be widely used and promoted.

Comparison of Bond Strength of Soft Denture Liner on the Denture Base Materials Produced by Different Methods and Effect of Thermocycling

Aim: This study set out to determine the tensile bond strength between denture bases (produced by 3D printing technology, conventional technique, and computer-aided design and computer-aided manufacturing [CAD/CAM] milled) and silicone-based soft lining material. The consequence of thermocycling on the bonding strength was also investigated. Materials and Methods: The bonding between denture foundation materials produced through three distinct techniques (conventional, CAD/CAM milled, and 3D printed) and silicone-based soft lining material was examined. Before tensile testing, half of the samples underwent thermocycling (5–55°C, 5,000 cycles) in 37°C distilled water for 48 hours. A universal testing apparatus employed a crosshead speed of 5 mm/min. The failure type was identified visually, and the maximum tensile strength was noted. The Shapiro-Wilk test and analysis of variances ( P = .05) were used to assess the statistics. Results: CAD/CAM milled denture base material (1.56 ± 0.62/1.36 ± 0.16 MPa) showed higher bond strength values than the other denture bases in the tensile test conducted before and after thermocycling ( P &lt; .001). The denture base material made conventionally had the lowest bond strength (1.02 ± 0.24/0.77 ± 0.1 MPa) ( P &lt; .001). The tensile bond strength values of the conventional and 3D printing groups showed a statistically significant drop before and after thermocycling ( P = .001). Regardless of thermocycling, adhesive failure was primarily seen in all groups (76.6%). Conclusion: Compared to conventionally produced denture bases, the bond strength of soft relining materials to CAD/CAM milled and 3D printed denture base is different. In denture base materials that are conventionally, CAD/CAM and 3D printed, the thermocycling method reduced bonding strength values.

3D versus 4K laparoscopic vaginal cuff closure after hysterectomy by surgeons in training: a prospective randomised trial.

Technological advances in visual systems have contributed to overcoming the limitations in spatial perception of minimally invasive techniques. To date, there is a lack of literature on the advantages of 3D vision systems over 4K in laparoscopic surgery, although benefits have been observed in the training setting. To compare operating times, perioperative outcomes, and task achievement using 3D and 4K vision systems for vaginal cuff closure performed by residents during total laparoscopic hysterectomy (TLH). All surgeons in training have obtained the Gynaecological Endoscopic Surgical Education and Assessment (GESEA) certificate. This is a prospective randomised trial (NCT04637022). Women undergoing total hysterectomies for benign conditions between January 2021 and November 2023 were enrolled in the study. Vaginal cuff closures were performed by surgeons in training who had obtained the second level of the GESEA programme certificate. Fifty-four patients were enrolled. There were no statistically significant differences in time between 3D and 4K vision for vaginal cuff closure (p=0.918). No statistically significant differences were observed for mean estimated blood loss (EBL) (overall: 62.85 ± 22.73mL; 3D: 65 ± 24.83mL; 4K: 61.11 ± 21.18; p=0.556) and median hospital stay (p=0.234). Three non-severe intraoperative complications in the 3D group (p=0.048) and three postoperative complications in the entire cohort (p=0.685) were reported. The operating time for vaginal cuff closure performed by trainee surgeons is similar when comparing 3D vision during conventional laparoscopy and 4K vision systems. The choice of surgical vision systems may be guided by a cost analysis and surgeon preferences. Substantial evidence is lacking regarding the advantages of incorporating 3D vision into standard laparoscopy for gynaecological surgery. This research seeks to assess whether the 3D visual system can provide benefits as compared to 4K visualisation during laparoscopic vaginal cuff closure performed by surgeons in training within the GESEA 2 certification programme.

SURGICAL OUTCOMES AND INTRAOPERATIVE PARAMETERS OF THREE-DIMENSIONAL VISUALIZATION SYSTEM VERSUS CONVENTIONAL MICROSCOPES FOR MACULAR SURGERY IN HIGHLY MYOPIC EYES: A Prospective Randomized Clinical Trial.

To investigate the surgical outcomes and intraoperative parameters of 3D visualization system for macular diseases in highly myopic eyes. In this single-center, prospective, randomized, comparative interventional study, 40 highly myopic eyes (axial length > 26 mm) were randomly assigned to either a 3D visualization system or a conventional microscope group. Surgical outcomes and intraoperative parameters, including the number of indocyanine green injections, surgical time, and epiretinal membrane/internal limiting membrane peeling time, were compared. The 3D group required significantly fewer indocyanine green injections (1.3 ± 0.5 vs. 2.3 ± 0.7, P < 0.001), had shorter epiretinal membrane/internal limiting membrane peeling times (522.8 ± 258.0 vs. 751.8 ± 320.2 seconds, P < 0.05), and experienced fewer intraoperative retinal hemorrhages (0 vs. 7 cases, P < 0.05) compared with the conventional microscope group. Anatomical and functional outcomes were comparable between the two groups. The 3D system exhibited a lower number of indocyanine green injections, shorter epiretinal membrane/internal limiting membrane peeling times, and a reduced incidence of intraoperative retinal hemorrhages, suggesting the 3D visualization system may offer advantages for macular surgery in highly myopic eyes.

Evaluation of Remote Surgical Hands-on Training in Veterinary Education Using a Hololens Mixed Reality Head-Mounted Display.

Conferencing system-assisted online classes have been conducted worldwide since the COVID-19 pandemic, and the use of three-dimensional glasses may improve pre-clinical veterinary education. However, students' satisfaction with this technique rather than their ability to perform surgery using these items has not been assessed. This study could potentially assess students' satisfaction with technique/instruction rather than their ability to perform surgery using these items.This study aimed to evaluate the effectiveness of remote online hands-on training in veterinary education using 3D glasses. Sixty students enrolled at the Faculty of Veterinary Medicineat Yamaguchi University voluntarily participated and were randomly divided into a 3D glasses and tablet group, each with 30 students. Each student completed one orthopedic and one ophthalmological task. The orthopedic task was performing surgery on a limb model, whereas the ophthalmological task involved incising a cornea on an eye model. The 3D glasses group participated in the ophthalmology task, then the orthopedic task, at a separate venue from the instructor. The tablet group participated in the same tasks using a tablet. In the student questionnaire, orthopedic screw fixation showed significantly higher levels of satisfaction in the 3D glasses group than in the tablet group, indicating a preference for this method. By contrast, for ophthalmic corneal suturing, the tablet group showed a significantly higher level of satisfaction than the 3D glasses group. Our findings showed that 3D glasses have a high educational value in practical training requiring depth and angle information.