Search Results (4,867)

This study aimed to evaluate the placement accuracy and reproducibility of Surface Guided Radiotherapy (SGRT) compared with the conventional tattoo/laser method in patients undergoing radiotherapy for abdominal malignancies. A retrospective analysis was conducted on 43 patients treated with either SGRT (Group A) or the tattoo/laser technique (Group B). Patients in both groups underwent CBCT to quantify the positioning shifts in the vertical (Svrt), lateral (Slat) and longitudinal (Slng) axes, as well as the total shift. Statistical indicators including median, interquartile range (IQR), and range were calculated, and Mann–Whitney U tests were performed due to non-normal data distribution. Median values in all axes were same between groups: Svrt = 0.4 cm, Slat = 0.2 cm, Slng = 0.4 cm. Group A showed a higher total median shift equal to 0.8 cm versus 0.7 cm of Group B. However, IQRs were smaller in the Group B for all directions and total shift, indicating greater method consistency. Statistically significant differences (p < 0.05) were observed in all axes, except the vertical. These findings suggest that, while SGRT achieves comparable median alignment, its use in a highly variable anatomical region such as the abdomen may be associated with greater setup variability. Full article

The increasing demand for sustainable construction materials has driven interest in utilizing waste biomass within polymer composites. Rigid polyurethane foams, widely valued for thermal insulation, exhibit a significant flammability issue. This study investigates the impact of incorporating various waste biomass materials, including brewers’ spent grain, coffee grounds, and soybean husk and their combustion ashes on the selected properties of rigid polyurethane foams. The primary objective is to assess the potential of these eco-friendly additives as replacements for traditional raw materials, aiming to enhance fire resistance and thermal stability and thereby promoting circular economy principles in the construction sector. Composite foam samples were fabricated using a mixing and casting technique, incorporating 5% wt. of fillers into the polymer matrix. Thermal stability and flammability were evaluated using cone calorimetry and thermogravimetric analysis. The findings indicated that while biomass inclusion did not significantly improve char formation, the addition of ash substantially increased char yield, a critical factor in fire suppression. Although biomass and ash may influence flammability, they do not inherently bolster the intrinsic thermal stability of the polyurethane matrix itself. Full article

Background: Autologous tooth-derived grafts have recently gained attention as an innovative alternative to conventional biomaterials for alveolar ridge preservation (ARP) and augmentation (ARA). Their structural similarity to bone and osteoinductive potential support clinical use. Methods: This systematic review was conducted according to PRISMA 2020 guidelines and registered in PROSPERO (CRD420251108128). A comprehensive search was performed in PubMed, Scopus, and Web of Science (2010–2025). Randomized controlled trials (RCTs), split-mouth, and prospective clinical studies evaluating autologous dentin-derived grafts were included. Two reviewers independently extracted data and assessed risk of bias using Cochrane RoB 2.0 (for RCTs) and ROBINS-I (for non-randomized studies). Results: Nine studies involving 321 patients were included. Autologous dentin grafts effectively preserved ridge dimensions, with horizontal and vertical bone loss significantly reduced compared to controls. Histomorphometric analyses reported 42–56% new bone formation within 4–6 months, with minimal residual graft particles and favorable vascularization. Implant survival ranged from 96–100%, with stable marginal bone levels and no major complications. Conclusions: Autologous tooth-derived biomaterials represent a safe, biologically active, and cost-effective option for alveolar bone regeneration, showing comparable or superior results to xenografts and autologous bone. Further standardized, long-term RCTs are warranted to confirm their role in clinical practice. Full article

Background/Objectives: Integrating 3D visualization technologies, including virtual reality (VR), augmented reality (AR), and mixed reality (MR), into dental education may enhance students’ understanding of facial anatomy and clinical procedures. This study aimed to assess dental students’ perceptions of using MR for three-dimensional visualizations of impacted teeth. Methods: Cone-beam computed tomography (CBCT) scans of patients with impacted teeth were retrospectively selected from a university clinic database. The CBCT images were processed to adjust contrast for optimal visualization before being uploaded to MR goggles (HoloLens 2). A total of 114 final-year dental students participated, each manipulating the 3D images in space using the goggles. Following this, they completed a seven-question survey on a five-point Likert scale (1 = strongly agree, 5 = strongly disagree), evaluating image quality and the usefulness of 3D visualization. Results: The study group consisted of 29 males and 85 females (mean age = 24.11 years, SD = 1.48). The most favorable responses were for enhanced visualization of the impacted tooth’s position relative to adjacent structures and the inclusion of 3D image visualization as a teaching aid, which benefited students while learning and allowed them to better understand the course of the procedure for exposure/extraction of the impacted tooth, with median scores of 1, indicating a highly favorable opinion. A statistically significant relationship was found between the responses of females and males regarding the quality of the presented image using HoloLens 2 goggles. No significant correlation was found between participants with and without prior experience using VR/MR/AR. No significant correlation was found between age and responses. Conclusions: Students reported an improved understanding of the relationships between impacted teeth and adjacent structures, as well as potential benefits for clinical training. These findings demonstrate a high level of acceptance of MR technology among students; however, further research is required to objectively assess its effectiveness in enhancing learning outcomes. Full article

Objectives: Retinitis pigmentosa (RP) is commonly initiated by rod photoreceptor degeneration due to genetic mutations, followed by secondary cone loss and progressive blindness. Preserving rod function during the earlier stages of RP is a key therapeutic goal, as rod survival supports cone maintenance and delays vision loss. In this study, we investigated the therapeutic potential of transient knockdown of retinoid-related orphan receptor beta (RORB) using a cell-penetrating asymmetric small interfering RNA (cp-asiRORB) in Rho^P23H mice, a model of autosomal dominant RP. While the role of RORB in the adult retina remains unclear, prior studies of related nuclear receptors suggest potential involvement in proteostasis. Based on this, we hypothesized that persistent RORB expression may influence photoreceptor homeostasis under degenerative stress. Methods: We first optimized the cp-asiRORB design to enhance gene silencing and cellular uptake. In vitro studies were conducted under proteotoxic stress. In vivo studies involved intravitreal administration of cp-asiRORB in Rho^P23H mice. Furthermore, single-cell RNA sequencing of rod photoreceptors was performed. Results: In vitro studies demonstrated that RORB knockdown improved cell viability, reduced apoptosis, and diminished aggresome formation under proteotoxic stress. Intravitreal administration of cp-asiRORB in Rho^P23H mice effectively reduced RORB expression in the retina, leading to improved photoreceptor survival and preserved visual function. Single-cell RNA sequencing revealed upregulation of proteasomal subunit genes in cp-asiRORB-treated eyes, indicating enhanced proteostasis. Conclusions: Together, these results demonstrate that transient suppression of RORB mitigates proteotoxic stress and slows RP progression, highlighting a novel RNAi-based therapeutic strategy for retinal degeneration. Full article

Background: Orthodontically driven osteogenesis (ODO) is a surgical tunnel modification of periodontally accelerated osteogenic orthodontics (PAOO), combining selective corticotomy with bone grafting in sequential and/or segmental fashion. This is a minimally invasive approach that enhances periodontal health and allows orthodontic tooth movement beyond the original alveolar envelope. Considering the lack of long-term three-dimensional data on orthodontically driven osteogenesis (ODO), this study aims to quantitatively assess the long-term stability of alveolar bone and buccal cortical thickness following ODO, using CBCT imaging. The null hypothesis is that ODO does not result in significant changes in alveolar bone volume or cortical thickness over a seven-year follow-up period. Methods: Twenty patients (13 females, 7 males; mean age 27.4 ± 5.3 years) who had undergone orthodontically driven osteogenesis (ODO) using a minimally invasive tunnel approach and segmental corticotomy protocol followed by clear aligner therapy were retrospectively evaluated. The mean follow-up period after treatment was 7 years (range: 5–15 years). Cone beam computed tomography (CBCT) scans were obtained at one year postoperatively (T1) and again at the long-term follow-up visit (T2). Buccal bone thickness measurements were taken at standardized levels (3 mm, 5 mm, and 7 mm apical to the cementoenamel junction) and compared between T1 and T2 to evaluate bone stability over time. In addition, histologic evaluation of the previously grafted area was performed in two patients: one sample was collected during an alveolar ridge augmentation procedure six months after ODO, and the other during orthognathic surgery eight months after ODO. The samples were analyzed to assess new bone formation and integration of graft material. Results: Radiographic analysis showed long term stability of the new bone support. Histologic examination showed newly formed lamellar and reticular bone. Bone marrow showed no inflammatory infiltration, and bone particles were still detectable but incorporated in the newly created bone. Conclusions: Based on these findings, ODO appears to be a promising technique that could induce stable bone osteogenesis. A larger cohort study can enhance the evidence of these promising results to popularize this technique. Full article

Power outages in non-faulted zones caused by system failures significantly reduce the reliability of distribution networks. To address this issue, this paper proposes a fault self-healing technique based on the integration of soft open points (SOPs) and network reconfiguration. A mathematical model for power restoration is developed. The model incorporates SOP operational constraints and the stochastic output of photovoltaic (PV) distributed generation. And this formulation enables the determination of the optimal network reconfiguration strategy and enhances the restoration capability. The study first analyzes the operational principles of SOPs and formulates corresponding constraints based on their voltage support and power flow regulation capabilities. The stochastic nature of PV power output is then modeled and integrated into the restoration model to enhance its practical applicability. This restoration model is further reformulated as a second-order cone programming (SOCP) problem to enable efficient computation of the optimal network configuration. The proposed method is simulated and validated in MATLAB R2019a. Results demonstrate that combining the SOP with the reconfiguration strategy achieves a 100% load restoration rate. This represents a significant improvement compared to traditional network reconfiguration methods. Furthermore, the second-order cone programming (SOCP) transformation ensures computational efficiency. The proposed approach effectively enhances both the fault recovery capability and operational reliability of distribution networks with high penetration of renewable energy. Full article

Background/Objectives: Periradicular disease is largely microbial in origin. Even gutta-percha (GP) cones manufactured under aseptic conditions can acquire contaminants during handling or storage, undermining otherwise adequate canal preparation. To assess residual antimicrobial activity on GP cones after brief exposure to five endodontic disinfectants: sodium hypochlorite (NaOCl) 1%, 2.5%, 5.25%; chlorhexidine (CHX) 2%; and glutaraldehyde 2% against Enterococcus faecalis and Candida albicans. Methods: Standardized GP cones were dipped for 5–120 s, blotted on neutralizing gauze, and placed on agar inoculated with either organism. Using an agar diffusion approach, inhibition-zone diameters were recorded at 0, 24, and 48 h. Data were summarized using descriptive statistics (means, standard deviations, and 95% confidence intervals) for each disinfectant–dip-time combination. Results: By 24 h, inhibition zones were observed for most disinfectants; for C. albicans, glutaraldehyde 2% showed no measurable effect. At later time points, performance depended on both disinfectant and contact time. For E. faecalis, NaOCl 2.5% and 5.25% yielded the largest zones at 48 h (20–21 mm at 120 s), whereas NaOCl 1% was smaller (10 mm) and glutaraldehyde 2% modest (9 mm). For C. albicans, NaOCl 2.5% and CHX 2% were most effective at 48 h (17–19 mm at 120 s); NaOCl 5.25% was intermediate, NaOCl 1% weak, and glutaraldehyde 2% showed no measurable antifungal effect. Longer immersions (≥45 s) consistently increased inhibition zone diameters. Conclusions: Residual antimicrobial activity on GP cones depends on both the agent and the immersion time. For E. faecalis, higher concentration NaOCl produced the largest zones at short contact time, whereas for C. albicans, CHX 2% and NaOCl 2.5% provided the most reliable carryover. Selecting an appropriate concentration and allowing sufficient dip time may reduce reinfection risk at obturation. Full article

Background: The posterosuperior maxillary region poses a challenge in orthognathic surgery due to its complex three-dimensional anatomy. The pterygomaxillary suture (PMS) is a key landmark for various procedures. Understanding its anatomical relationships is essential to improving surgical precision. Methods: A retrospective analysis of CBCT images from 120 patients aged 18–70 years at Ankara Medipol University was conducted. Patients were categorized into skeletal Classes I, II, and III according to the ANB angle. Linear and angular measurements of the PMS and adjacent structures were performed. The statistical analysis included the Shapiro–Wilk, Independent t-test, Mann–Whitney U test, and regression analysis (p < 0.05). Results: There were clear differences between the skeletal groups. Class II and III patients had a lesser lateral PMS–baseline intersection distance (IV–VI) and Class II had a lesser medial PMS–baseline perpendicular distance (VV′) compared to Class I (p < 0.05). Additionally, the angle V–IV–VI was significantly narrower in Class II and III groups, indicating altered PMS orientation in these skeletal patterns. Conclusions: PMS morphology, including thickness, width, and angulation, is influenced by skeletal pattern. A preoperative CBCT assessment and individualized surgical planning are essential to ensure the safety and accuracy of Le Fort I osteotomies, especially in Class II and III patients. Full article

There is a strong coupling between two arms in cooperative operations of dual-arm robots. To enhance the coordination and cooperation ability of dual-arm robots, a force-closure-based weighted hybrid force/position fuzzy coordination control method is proposed. Firstly, to improve the grasping stability of dual-arm robots, the force-closure dynamic constraints are established by combining the friction cone constraints with the force and torque balance constraints. Then the optimal distribution of contact force is performed according to the minimum energy consumption principle. Secondly, to enhance the coordination of dual-arm robots, the weighted hybrid force/position control method is modified by adding the synchronization error between two arms. Then the Lyapunov method is adopted to prove the stability of the proposed coordination control method. Thirdly, the fuzzy self-tuning technique is adopted to adjust the control gains automatically. Lastly, a simulation and experiment are performed for collaborative transport. The results show that, compared with the position coordination control and the traditional hybrid force/position control, the weighted hybrid force/position fuzzy coordination control can improve control accuracy and has good cooperation ability and strong robustness. Therefore, the proposed method can effectively realize the coordination control of dual-arm robots. Full article

Background: Obstructive Sleep Apnea Syndrome (OSAS) is a prevalent and underdiagnosed condition with significant systemic and quality-of-life impacts. While polysomnography remains the gold standard for diagnosis, cone-beam computed tomography (CBCT) presents a potential adjunctive imaging tool for anatomical airway evaluation. Objective: We aimed to assess the effectiveness of three-dimensional airway evaluation via CBCT as a complementary diagnostic tool for OSAS. Methods: A diagnostic test study (experimental pilot study) was conducted using CBCT scans of 30 patients, divided into two groups: 15 scans from patients with a confirmed OSAS diagnosis through polysomnography and 15 scans from healthy controls. Five tomographic variables were analyzed: anteroposterior distance, lateral distance, minimum cross-sectional area, airway volume, and airway shape. Statistical analysis was performed comparing both groups. Results: The minimum cross-sectional area and airway volume showed statistically significant differences between the OSAS and control groups (p = 0.038 and p = 0.0055, respectively). Anteroposterior and lateral distances showed trends toward significance but were not statistically significant. Conclusions: CBCT-based airway analysis, particularly focusing on volumetric and cross-sectional area parameters, demonstrates strong potential as a complementary tool in the diagnosis of peripheral-type OSAS. However, it cannot replace polysomnography, especially for central OSAS diagnosis. Full article

A new cascaded model is proposed to improve the accuracy and early warning capability of predicting mine water inrush accidents. The model sequentially applies a Bidirectional Long Short-Term Memory Network (BiLSTM) and a Variational Autoencoder (VAE) to capture the spatio-temporal dependencies between borehole water level data and water inrush events. First, the BiLSTM predicts borehole water levels, and the prediction errors are analyzed to summarize temporal patterns in water level fluctuations. Then, the VAE identifies anomalies in the predicted results. The spatial correlation between borehole water levels, induced by the cone of depression during water inrush, is quantified to assign weights to each borehole. A weighted comprehensive anomaly score is calculated for final prediction. In actual water inrush cases from Xin’an Coal Mine, the BiLSTM-VAE model triggered high-risk alerts 9 h and 30 min in advance, outperforming the conventional threshold-based method by approximately 6 h. Compared with other models, the BiLSTM-VAE demonstrates better timeliness and higher accuracy with lower false alarm rates in mine water inrush prediction. This framework extends the lead time for implementing safety measures and provides a data-driven approach to early warning systems for mine water inrush. Full article

Background/Objectives: Although surgeries employing cone-beam computed tomography (CBCT) for small lung lesions have been reported, the association between CBCT scan frequency and patient radiation exposure remains unclear. This study aimed to investigate patient radiation doses from CBCT during thoracic surgeries, and the patient radiation doses were compared with those from other preoperative marking methods. Methods: This multicenter prospective study included 81 patients who underwent surgery for small lung lesions requiring marking between January 2021 and June 2024 at three institutions. CBCT-guided surgeries involved the use of metal clips in a hybrid operating room with 1–4 scans, depending on the lesion. For other preoperative marking methods, hook-wire or virtual-assisted lung mapping (VAL-MAP) was used. Patient radiation doses were measured using wearable dosimeters at five anterior thorax sites, and the total dose was compared across methods. Results: The study included 81 patients: CBCT (n = 61), VAL-MAP (n = 10), and hook-wire (n = 10). CBCT cases were distributed as follows: single scan (n = 10), double scans (n = 34), triple scans (n = 15), and quadruple scans (n = 2). The radiation doses were 86.9 ± 61.7 mGy for hook-wire, 39.8 ± 27.5 mGy for VAL-MAP, and 11.0 ± 6.5 mGy for single-scan CBCT, 17.3 ± 7.8 mGy for double scans, 23.1 ± 14.0 mGy for triple scans, and 22.7 ± 0.1 mGy for quadruple scans. Although radiation exposure increased with more CBCT scans, performing up to triple scans resulted in significantly lower exposure compared to other methods. Conclusions: Intraoperative CBCT is a feasible and safe technique for identifying small lung lesions, providing lower radiation exposure compared to other preoperative localization methods. Full article

Successful health management in older adults requires adequate nutrition, which is often compromised by oral health issues like edentulism. Tooth loss can reduce masticatory function, especially when rehabilitation treatments fail. The present study aims to generate initial information on the potential effects of the placement of mandibular mini-implants in patients with complete maxillary and mandibular dentures on mandibular kinetics, electromyographic activity, and quality of life. Participants with complete dentures, adequate mandibular bone height, and good general health were recruited. All underwent cone beam computed tomography for diagnosis and planning to place two mandibular mini-implants. Mandibular movements were analyzed using electromagnetic articulography and electromyography before treatment and five months after implant placement. Oral health-related quality of life (OHRQoL) was assessed using the OHIP-7sp at baseline and six months post-treatment. Five subjects were included (mean age 69.7 ± 10.8 years). All mini-implants demonstrated a 100% initial success rate. At five months, significant improvements were observed in the vertical range of maximum opening, as well as in the area, trajectory, and range of frontal and sagittal movement envelopes (p < 0.05)—along with increased movement symmetry. OHRQoL also improved, with greater esthetic satisfaction, communication, and social engagement. Mandibular mini-implants improved mandibular movements and prosthetic stability, enhancing patients’ oral health-related quality of life without altering muscle activity. Full article

Background/Objectives: The hyoid bone plays a central role in functions such as swallowing, speech, and airway maintenance, and its morphology may vary with anatomical and functional parameters. This study aimed to evaluate the influence of skeletal class, respiratory mode, age, and sex on the morphometric features of the hyoid bone using cone-beam computed tomography (CBCT). Methods: A total of 560 CBCT scans (295 females, 265 males; aged 8–73 years) were retrospectively analyzed. Hyoid angle, horizontal length, and vertical height were measured using Dolphin 3D software. Participants were categorized by skeletal class (I, II, III), breathing pattern (nasal vs. oral), and age group. Data were analyzed using robust three-way ANOVA and Bonferroni post hoc tests. Results: In females, nasal breathers exhibited significantly larger hyoid angles and vertical heights than oral breathers (p < 0.001), independent of age and skeletal class. In males, both age and breathing mode significantly influenced hyoid angle and vertical length (p < 0.001). Vertical height was also significantly greater in skeletal Class I compared to Class III (p = 0.008). Notably, significant respiration–skeletal class interaction was found in females (p = 0.029) but not in males. Conclusions: Hyoid bone morphology is affected by age, breathing pattern, and skeletal class, with sex-specific differences. Nasal breathing and younger age were associated with more inferior and angularly favorable hyoid positions, which may have implications for airway stability and craniofacial development. Full article