Search Results (2,271)

Background: Early detection of dental caries is essential for effective oral health management. Current diagnostic workflows rely heavily on radiographic imaging, which involves infrastructure requirements, workflow coordination, and resource considerations that may limit frequent use in high-throughput or resource-constrained settings. These contextual factors motivate exploration of adjunct screening concepts that could support front-end triage decisions within existing care pathways. This study evaluates, in simulation, whether modeled tooth-percussion response signals contain sufficient discriminative information to justify further translational and managerial investigation. Implementation costs, workflow optimization, and economic outcomes are not evaluated directly; rather, the objective is to assess whether the technical preconditions for a potentially scalable screening concept are satisfied under controlled in silico conditions. Methods: An in silico model of tooth percussion was developed in which enamel, dentin, and pulp/root structures were represented as a simplified layered mechanical system. Impulse responses generated from simulated tapping were used to compute the modeled surface-vibration response (enamel-layer displacement), which served as a proxy for a measurable percussion-related signal (e.g., contact vibration), rather than a recorded acoustic waveform. Carious conditions were simulated through depth-dependent reductions in stiffness and effective mass and increases in damping to represent enamel and dentin demineralization. A synthetic dataset of labeled simulated signals was generated under varying structural parameters and measurement-noise assumptions. Machine-learning models using Mel-frequency cepstral coefficient (MFCC) features were trained to classify healthy teeth, enamel caries, and dentin caries at a screening (triage) level. Results: Under baseline simulation conditions, the classifier achieved an overall accuracy of 0.97 with balanced macro-averaged F1-score (0.97). Misclassifications occurred primarily between healthy and enamel-caries categories, whereas dentin-caries cases were most consistently identified. When measurement noise and structural variability were increased, performance declined gradually, reaching approximately 0.90 accuracy under the most challenging simulated scenario. These results indicate that discriminative information is present within the modeled signals at a screening (triage) level, meaning that higher-risk categories can be distinguished probabilistically rather than with definitive diagnostic certainty. Sensitivity and specificity trade-offs were not optimized in this study, as the objective was to assess separability rather than to define clinical decision thresholds. Conclusions: Within the constraints of the in silico model, simulated tooth-percussion response signals demonstrated discriminative patterns between healthy, enamel caries, and dentin caries categories at a screening (triage) level. These findings establish technical plausibility under controlled simulation conditions and support further investigation of percussion-based screening as a potential adjunct to clinical assessment. From a healthcare management perspective, the present results address a prerequisite question—whether such signals contain sufficient information to justify translational research, rather than demonstrating workflow optimization, cost reduction, or system-level impact. Clinical validation, threshold optimization, and implementation studies are required before managerial or operational benefits can be evaluated. Full article

Background: The choice of mechanical prosthesis for mitral valve replacement (MVR) is critical, yet data comparing long-term outcomes across different valve types are still needed. This study aimed to compare the long-term clinical and echocardiographic outcomes of four distinct mechanical mitral valve prostheses. Methods: We retrospectively analyzed 431 patients who underwent mechanical MVR between 2009 and 2022 with one of four valve types: Carbomedics (n = 112), Bicarbon (n = 176), ATS (n = 89), or On-X (n = 54). A competing risk regression model was used to identify predictors of a composite endpoint (valve thrombosis, reoperation, stroke, pulmonary embolism, and major bleeding), accounting for all-cause mortality. Longitudinal echocardiographic data were analyzed using linear mixed-effects models. Results: The median follow-up was 62 months. The cumulative incidence of the composite endpoint at 10 years was 14% for the On-X valve, 12% for the Bicarbon valve, 9.5% for the Carbomedics valve, and 7% for the ATS valve. After adjusting for confounders, the type of valve prosthesis was not significantly associated with the composite endpoint. Significant predictors of adverse events included coronary artery disease (Sub-distribution Hazard Ratio [SHR] 2.70, p = 0.023), peripheral artery disease (SHR 6.29, p = 0.007), and smaller valve size (SHR 0.87, p = 0.037). No significant difference in overall survival was observed between the groups (log-rank p = 0.904). All valve types were associated with favorable LV remodeling. The Carbomedics group showed the greatest reduction in left ventricular end-diastolic diameter, likely reflecting regression to the mean given the larger baseline ventricular dimensions in this group. Conclusions: The type of mechanical mitral valve did not significantly influence long-term thromboembolic and bleeding events or overall survival. Patient-specific factors and valve size were the primary determinants of adverse outcomes. The observed differences in ventricular remodeling may warrant further investigation. Full article

Background/Objectives: Saliva plays an essential role in maintaining the oral ecological balance, and its quantitative and qualitative characteristics may influence susceptibility to dental caries. The aim of this study was to determine susceptibility to dental caries based on the DMFT index and to establish a correlation between caries experience and salivary parameters in a group of young adults. Methods: This cross-sectional study was conducted between July and November 2025 on a sample of 87 fourth-year students from the Faculty of Dentistry in Craiova. Each participant underwent an intraoral clinical examination to determine the DMFT index. The salivary parameters assessed included unstimulated salivary flow rate, saliva consistency, salivary pH, stimulated salivary flow rate, and buffering capacity, using the GC Saliva-Check Buffer kit. Statistical analyses were performed using SPSS (Statistical Package for Social Sciences) software, version 26 (SPSS Inc., Armonk, NY, USA). Results: The mean DMFT index value for the entire sample was 8.26 ± 4.481, with higher values observed among female participants. Low salivary pH was significantly associated with higher DMFT values. Participants with low or very low buffering capacity exhibited higher DMFT values compared to those with normal capacity, indicating that a reduced ability to neutralize salivary acidity is associated with increased caries activity. Conclusions: The results indicate that salivary pH and buffering capacity are important factors in dental caries susceptibility among young adults. The integration of salivary testing into the diagnostic assessment of caries risk may contribute to personalized and effective preventive strategies. Full article

Background: Transtibial prostheses are commonly classified as endoskeletal or exoskeletal and differ in weight, adaptability, and mechanical response, which may influence gait performance. This study examined whether prosthesis type affects overground walking movement structure and neuromuscular control and assessed the relationship between walking speed and neuromuscular control. Methods: Principal component analysis (PCA) was applied to kinematic marker data from 20 unilateral transtibial amputees using either endoskeletal (n = 10; 54.7 ± 6.1 years) or exoskeletal prostheses (n = 10; 57.9 ± 8.7 years) during self-selected overground walking. Principal movements (PMs) were extracted to represent functionally meaningful gait components. Movement structure was evaluated using the relative explained variance of PM positions (rVAR), whereas neuromuscular control was quantified using the root mean square of PM accelerations (RMS; acceleration magnitude) and the number of zero crossings (N; regularity/predictability). Group differences were examined using covariate-adjusted analyses, controlling for preferred walking speed. Results: No significant differences in walking movement structure were found between prosthetic types. Unadjusted analyses suggested greater swing-phase acceleration (PM₂) and lower neuromuscular variability across PM₁–PM₄ in the endoskeletal group; however, these effects were no longer significant after adjusting for BMI and walking speed. Walking speed showed strong associations with neuromuscular control (p ≤ 0.003), with faster speeds linked to greater swing-phase acceleration and reduced variability. Conclusions: Walking movement structure and neuromuscular control were comparable between prosthetic types, while walking speed emerged as a key factor in gait evaluation among transtibial amputees. Full article

In implant treatment in the aesthetic zone, high aesthetic quality is required in addition to functionality and long-term stability when reconstructing defects in peri-implant tissues. Post-traumatic cases often present with extensive loss of both hard and soft tissues, making the selection of an appropriate grafting method essential. This report describes a case in which an interpositional gingival graft (IGG) and a strip gingival graft (SGG) were combined to regenerate peri-implant soft tissue following guided bone regeneration (GBR), maintaining favorable tissue morphology and aesthetics for six years. The patient was a 53-year-old woman who suffered trauma after falling down stairs, resulting in a fractured bridge in the right maxillary canine region and crown fracture. The traumatized tooth was extracted, and GBR was performed to restore hard tissue volume. Subsequently, IGG and SGG were used to improve soft tissue thickness, interproximal papilla height, and a healthy mucogingival junction (MGJ). A cantilever implant prosthesis was selected as the final restoration. Over six years, no gingival recession or marginal bone loss was observed, and excellent aesthetic stability was maintained. A mini-review of published reports on IGG and SGG demonstrated their efficacy in enhancing soft tissue volume. The findings of this case suggest that a comprehensive approach—including bone augmentation, soft tissue grafting, and prosthetic design—can provide predictable, long-term aesthetic and functional outcomes in complex post-traumatic cases (223). Full article

Background/Objectives: One key objective in temporomandibular joint replacement is to precisely position the implant according to the virtual surgical plan, utilizing drilling and osteotomy guides for accuracy. However, implementing this process can be challenging, as—even though the drilling and osteotomy guides should only fit in one position—there often are still multiple potential positions for both guides and implants on smooth bony surfaces. Even minor deviations in the implant’s placement can affect wear, influence biomechanical behavior, and lead to adverse outcomes. Intraoperative navigation has emerged to verify the alignment of implants with the preoperatively planned ideal position. While the use of navigation systems in TMJ surgery is well documented for certain procedures, its application in TMJ replacement cases has been limited. Methods: In this study, two methods to improve the accuracy of TMJ replacement are introduced: a new marker-based navigation workflow and the use of orientation screws in two patients. Results: Unlike conventional navigation methods, the marker-based system provides a more intuitive method for assessing the 3D orientation of the TMJ implant concerning the planned position, enhancing surgical accuracy. The addition of a guiding screw provides a reference point to enhance the accuracy of guide placement. Conclusions: The accurate placement of the prosthesis largely relies on the precise positioning of the guides. Even slight inaccuracies in the position of the TMJ prosthesis, resulting from suboptimal guide placement, can lead to significant negative clinical outcomes. Marker-based navigation and the use of guiding screws may potentially improve the precision of TMJ replacement procedures. Full article

Objective: This study aimed to quantitatively evaluate five opportunistic respiratory pathogens among individuals, with or without dentures, who have either healthy or diseased periodontal conditions. Methods: Saliva samples were obtained from 24 older adults. DNA extraction was performed, followed by a quantitative Polymerase Chain Reaction targeting five opportunistic respiratory pathogens, namely Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus pyogenes, Klebsiella pneumoniae, and Streptococcus agalactiae. The abundance of opportunistic pathogens among the four groups [denture-wearing with active periodontal disease (DAP), non-denture-wearing with active periodontal disease (NDAP), denture-wearing with stable periodontal health (DSP), and non-denture-wearing with stable periodontal health (NDSP)] were compared. Results: Saliva samples of all participants (100%) carried at least one opportunistic respiratory pathogen. Of the five pathogens, S. aureus, P. aeruginosa, K. pneumoniae, and S. agalactiae were present in more than 50% of the samples. A significant difference in the bacterial load of K. pneumoniae and P. aeruginosa was observed (p < 0.05). The quantity of P. aeruginosa in the NDAP group was significantly lower than the DSP group. However, for K. pneumoniae, no significant differences between the groups were detected. Conclusions: In this small pilot cohort, a relatively high prevalence and substantial microbial load of opportunistic respiratory pathogens were identified in the saliva of older adults. On the basis of these preliminary findings, optimal oral and denture hygiene care is suggested as a potential approach to reduce the presence and burden of respiratory pathogens in this population, although larger studies are required to confirm these associations and determine their clinical significance. Full article

This study presents a fully automatic hybrid framework for circle detection and geometric feature extraction from anteroposterior (AP) X-ray images. Detecting circular structures in X-ray imagery is challenging due to low contrast, noise, and metal-induced artifacts, which often limit the robustness of purely learning-based or purely geometric approaches. To address these challenges, a hybrid deep learning and computer vision pipeline is proposed that combines data-driven region localization with robust geometric fitting. A YOLOv5-based detector is first employed to identify a compact region of interest (ROI) containing circular components. Within this ROI, edge-based processing using Canny detection is applied, followed by an Edge-Snap refinement stage and robust RANSAC-based circle fitting with a Hough-transform fallback to ensure anatomically plausible circle estimation. The resulting circle centers and radii provide stable geometric parameters that can be consistently extracted across images with varying contrast, noise levels, and prosthesis appearances. The applicability of the proposed framework is demonstrated through a case study on hip prosthesis wear analysis, where the automatically detected circle parameters are used to compute medial, superior, and resultant displacement components using established two-dimensional radiographic formulations. Experimental evaluation on AP hip radiographs shows that the YOLOv5 detector achieves high ROI localization performance (mAP@0.5 = 0.971) and that the hybrid pipeline produces consistent circle parameters across longitudinal image sequences. Overall, the proposed method provides an end-to-end automatic solution for robust circle detection in X-ray imagery, with hip prosthesis wear presented solely as a case study without clinical or diagnostic claims. Full article

This case report describes the esthetic and functional rehabilitation of a 45-year-old male patient presenting with a missing maxillary right lateral incisor (#12). Due to persistent insufficiency of alveolar ridge width following multiple augmentation procedures, implant placement was contraindicated. A minimally invasive prosthetic approach was therefore selected, consisting of a single-retainer lithium disilicate resin-bonded fixed dental prosthesis (RBFDP) combined with laminate veneers to optimize anterior esthetics. The cantilever design and adhesive protocol were selected based on biomechanical principles aimed at minimizing interfacial stresses and preserving enamel structure. The prosthesis was fabricated using a fully digital workflow, and adhesive bonding was performed following established ceramic and enamel surface conditioning protocols. The restoration fulfilled the patient’s esthetic and functional expectations, and clinical follow-up at 18 months demonstrated stable bonding, healthy peri-abutment tissues, and absence of technical or biological complications. This case highlights the role of lithium disilicate cantilever RBFDPs as a minimally invasive and clinically viable treatment option for the replacement of maxillary lateral incisors when implant therapy is contraindicated, with outcomes limited to short- to medium-term observation. Full article

Objectives: This study investigated the impact of age on the diagnostic accuracy and patient acceptance of two chewing efficiency tests: the digital Mini Dental Assessment (MDA) using carrots and the CHEW test by Slavicek using fruit gum, applied in both clinical and nursing home settings. Methods: Seventy participants aged 18 to 99 years from dental clinics and nursing homes were included. All participants received a standardized dental examination (reference standard) and performed the MDA and CHEW tests. Sensitivity, specificity, and AUC values were calculated using ROC analysis. Participants rated both tests in terms of taste, consistency, comprehensibility, required time, and subjective chewing sensation. Acceptance was analyzed across age groups and prosthesis types. Results: Both chewing efficiency tests showed good agreement with the clinical reference standard. The AUC was 0.72 for the MDA and 0.78 for the CHEW test (p = 0.192). Sensitivity was higher for the CHEW test (100%) compared to the MDA (83.3%), while the MDA demonstrated slightly higher specificity (59.6% vs. 55.8%). Age significantly influenced both diagnostic outcomes and test acceptance (p < 0.05). Younger participants (<70 years) were more often correctly classified as healthy and tended to prefer the MDA, whereas older participants (≥70 years) preferred the CHEW test, primarily due to taste. Misclassifications occurred most frequently among participants with complete dentures. Conclusions: Both the digital MDA and the CHEW chewing test demonstrated good diagnostic performance in identifying treatment need. Acceptance varied significantly with age, suggesting that test selection may be optimized based on patient characteristics. These simple and rapid assessments may support early detection of dental treatment needs in clinical and nursing home settings. Full article

Paravalvular leak (PVL) remains a clinically important complication after surgical or transcatheter valve implantation, presenting predominantly with heart failure (HF) and/or high-shear hemolysis. While redo surgery can be definitive, contemporary candidates frequently carry prohibitive operative risk, positioning transcatheter PVL closure as a key therapeutic alternative. However, available outcome data are largely derived from observational series and registries with heterogeneity in PVL mechanisms, prosthesis types, imaging protocols, and endpoint definitions. Standardized frameworks—such as those proposed by the PVL Academic Research Consortium—support harmonized PVL grading and clinically meaningful composite endpoints that integrate imaging/hemodynamic results with patient-centered outcomes. Across datasets, the most consistent determinant of benefit is residual PVL severity: procedural efficacy is most commonly defined as achieving ≤ mild residual regurgitation without prosthetic leaflet interference, device embolization, or major complications. This review provides a step-by-step, phenotype-driven approach to transcatheter PVL closure, emphasizing multimodality imaging (TEE and cardiac CT, with adjunct CMR and PET when appropriate), access and support planning tailored to valve position, and morphology-matched device selection—often requiring modular multi-device strategies for elongated crescentic channels, particularly in hemolysis-predominant presentations. We also synthesize evidence on complications and bailout management, with a focus on preventable high-severity events (leaflet impingement, embolization, stroke/air, vascular injury, tamponade) and standardized pre-release safety checks. Collectively, contemporary practice supports high implant success in experienced programs, with clinical improvement tightly coupled to procedural endpoint quality and careful Heart Team selection. Full article

Intracortical microstimulation (ICMS) is a promising approach for visual prostheses. We recently proposed using retinal neuromorphic spike trains derived from visual images as ICMS pulse sequences, and preliminarily recorded cortical voltage-sensitive dye (VSD) responses to such stimulation. To examine whether these cortical responses contain image information, we explore the feasibility of machine-learning–based decoding. However, constructing such a decoder requires large-scale datasets linking visual images, spike trains, and cortical responses, which are not yet experimentally available. Therefore, we generated surrogate data with a Wiener-system model that simulates VSD responses of the visual cortex to ICMS pulse trains. A convolutional neural network trained on these synthetic datasets successfully reconstructed images from the simulated cortical responses. This simulation work serves as a proof-of-concept study, demonstrating the computational feasibility of estimating visual information contained in neuromorphic ICMS-evoked cortical activity and providing a foundation for future physiological validation. Full article

Microbial communities on obturator prosthesis biofilms have yet to be investigated. This pilot study explores eukaryotes, prokaryotes, and viruses present on obturator prosthesis biofilms using metagenomics. The prostheses of the selected patients (n = 3) were collected and their biofilms were physically removed. The total genomic DNA was extracted, followed by metagenomic analysis. The microbial diversity in each of the investigated biofilms was exceptionally abundant. Between 2616 to 3024 species were detected in the three biofilms. The highest percentage included prokaryotes and unclassified species, followed by low percentages of fungi, viruses, and archaea. Unusual pathogens rarely reported in oral biofilms, such as Mycobacterium and other species, were also found at very low percentages. Unigenes for functional pathways related to metabolism, cellular processes, human disease, and other microbial unigenes were abundant. In addition, unigenes for several antibiotic-resistance mechanisms were also detected. This study reveals, for the first time, that biofilm formation on obturator prostheses comprises a variety of dynamic microbial communities, suggesting a putative role in health and disease in patients following maxillofacial surgery. Full article

Orthopedic surgery is undergoing a transformation driven by artificial intelligence (AI), which is reshaping clinico-surgical decision-making. While the operative strategy and professional responsibility traditionally relied on the surgeon’s intuition and manual skills, advanced algorithms now provide predictive, analytical, and procedural decision supports. This paradigm shift is redefining the concept of human error as well as the relationship between technological tools and human decision-makers. As a result, the foundational elements of the healthcare liability framework are being affected. This paper offers a narrative discussion on selected applications of artificial intelligence in orthopedic surgical practice, including patient risk stratification, surgical indication and prosthesis positioning, with a particular focus on the liability implications for healthcare professionals who rely on these systems in terms of therapeutic decision-making. The aim is then to provide a comprehensive medico-legal perspective within the highly regulated and high-risk field of biomedicine, acknowledging and critically assessing the roles and responsibilities of all stakeholders involved—patients, healthcare professionals, innovative technologies, healthcare organizations, and facility management—while balancing innovation, evidence-based practice, and accountability in healthcare delivery. Full article

Background: Language serves as a significant barrier to accessing dental services. Dental treatment options are often complex and involve terminology that is unfamiliar to most patients. In some cases, dental students may use technical terms that patients do not understand, leading to confusion and misunderstandings. Therefore, this study aimed to assess the language barriers faced by dental students and patients in Riyadh, Saudi Arabia. Methods: A mixed-methods research design was employed to evaluate language barriers between dental students and patients, as it provides an in-depth understanding and generates information beyond mere numerical data. The study was conducted from 1 September 2024, to 30 August 2025, in Riyadh, Saudi Arabia. Data collection primarily involved conducting interviews with focus group members using a comprehensive topic guide consisting of predetermined questions. Results: Forty dental students and forty patients agreed to participate in this study. The students encountered significant difficulty explaining terms such as crown lengthening (72.5%) and periodontitis (67.5%), while patients reported limited understanding of interim removable dental prosthesis (65%) and fixed dental prosthesis (60%). Comparative analysis indicated that sixth-year students reported significantly more difficulty explaining “crown lengthening” and “prefabricated post and core” compared to fifth-year students. It was also observed that patients’ educational level had a significant impact on their understanding of terms such as “interim dental prosthesis” and “removable dental prosthesis.” Qualitative analysis revealed patients’ partial understanding or misinterpretation of dental terminologies. Conclusions: Our findings indicate that language discordance, even among speakers of the same native language, can hinder effective communication, particularly when technical vocabulary is involved. Students may struggle to explain procedures in a manner that patients can easily understand. This can lead to incomplete patient comprehension and potential non-compliance with treatment recommendations. Hence, we recommend incorporating Arabic dental terminologies alongside English into the curriculum, developing bilingual glossaries, and using visual aids when communicating with patients. Full article