Search Results (133)

Outbreaks of the sharp-toothed bark beetle, Ips acuminatus, have become increasingly frequent across Europe, yet little is known about how natural enemy communities vary between bark beetle population phases. This study compared the composition, diversity, emergence patterns, and relationships of natural enemies associated with I. acuminatus in two Scots pine (Pinus sylvestris) forest areas representing endemic and post-outbreak population conditions in Latvia. Bark beetle colonized stem sections were collected and maintained under controlled laboratory conditions to quantify emerging insects. Community composition and diversity were analysed, and linear mixed-effects models were used to evaluate relationships between bark beetle and natural enemy densities. A total of 5468 insects representing 21 taxa emerged, including 12 natural enemy taxa. Natural enemy community composition and Shannon diversity were similar between areas/populations. However, the relationship between densities of I. acuminatus and natural enemies differed significantly between the two areas (p = 0.002), with a substantially stronger positive relationship detected in the one with an endemic population. Under laboratory conditions, parasitoids emerged synchronously with the I. acuminatus, whereas predator emergence peaked later. These findings indicate that compositionally similar natural enemy assemblages can exhibit different density relationships between systems representing contrasting bark beetle population conditions, emphasizing the importance of considering abundance relationships alongside community composition. Full article

Oral health represents a cornerstone of systemic health. Driven by diverse dietary structures and lifestyle habits, nearly everyone is affected by common oral diseases, including oral ulcers, tooth discoloration, and dental caries, etc. However, limited by the inherent properties of conventional oral biomaterials, existing clinical treatments still suffer from insufficient reliability and stability, leaving substantial clinical demands unmet. In recent years, functional hydrogels have aroused widespread interest in the biomedical field owing to their favorable biocompatibility, biodegradability, and tunable mechanical properties, exhibiting promising application potential in oral disease treatment. This paper reviews the recent progress of functional hydrogels in the treatment of oral diseases, with emphasis on their working mechanisms and therapeutic outcomes. Lastly, the current challenges and future opportunities of functional hydrogels in oral clinical applications are also critically discussed. This work is expected to provide valuable guidance for the design and development of innovative therapeutic strategies for oral diseases. Full article

Objectives: To evaluate and compare the tooth detection and numbering performance of two commercially available artificial intelligence (AI) software systems, ThakaaMed and EM2AI, in the automated detection and numbering of permanent teeth on panoramic radiographs. Methods: A retrospective study was conducted using a randomized sample of 595 panoramic radiographs obtained from multiple dental outpatient facilities. The sample included patients aged 6–18 years with mixed or permanent dentition. Ground truth (GT) annotations were established independently by three experienced dental clinicians using the FDI tooth numbering system. Each radiograph was analyzed using ThakaaMed Dental IQ (Version 1.9) and EM2AI (Version 3.2.0), and AI-generated outputs were compared with GT annotations. Tooth detection and numbering performance was assessed using sensitivity, specificity, and accuracy, and sensitivities and specificities were compared between the two AI systems across anatomical regions. Third molars were analyzed separately because of their variable developmental stages in mixed dentition radiographs. Results: EM2AI demonstrated superior performance in third molar detection compared with ThakaaMed. Excluding third molars, overall diagnostic accuracy was 96.81% for ThakaaMed and 99.48% for EM2AI. Regional analyses demonstrated significantly higher sensitivity for EM2AI in the upper anterior, lower anterior, and lower posterior regions, whereas no significant differences in specificity were observed between the two AI systems. EM2AI maintained consistently high tooth detection and numbering performance across anatomical regions. Conclusions: Both ThakaaMed and EM2AI demonstrated favorable tooth detection and numbering performance and potential utility as supportive tools in routine dental diagnostic and documentation workflows. EM2AI demonstrated greater consistency across anatomical regions and superior performance in third molar detection. These findings highlight the importance of evaluating AI systems across diverse anatomical regions and developmental stages when assessing their clinical applicability. Full article

Meso-scale ultrasonic vibration-assisted end milling (UVAEM) is an advanced manufacturing technique. UVAEM of Inconel 718 superalloy presents significant modeling challenges due to complex thermo-mechanical interactions and meso-scale size effects. This study introduces a machine learning framework that systematically compares Gaussian Process Regression (GPR), Support Vector Regression (SVR), Random Forest (RF), and Ridge Regression for predicting cutting force, tool wear, and surface roughness, thereby contributing to sustainable manufacturing. Experiments followed a Taguchi L16 orthogonal array with two replicates (n = 32), varying cutting speed (10–40 m/min), feed rate (0.01–0.025 mm/tooth), depth of cut (0.10–0.25 mm), vibration amplitude (0–9 μm), and tool coating (TiAlN, TiSiN, nACo, Uncoated). Tool coating was one-hot encoded, and strict leave-one-out cross-validation (LOOCV) with within-fold standardization ensured unbiased generalization metrics. Following nested hyperparameter tuning, SVR achieved the highest accuracy (R² = 0.9552, 0.9473, 0.9294), marginally outperforming GPR (R² = 0.9543, 0.9420, 0.9290). Ridge regression was competitive for tool wear (R² = 0.9235), while random forest ranked last due to limited ensemble diversity at n = 32. Pearson correlation identified depth of cut as the dominant driver of cutting force and surface roughness (r = 0.767, 0.759), cutting speed as the primary driver of tool wear (r = 0.663), and vibration amplitude as consistently beneficial across all three responses. SVR and GPR are recommended as reliable surrogate models for process optimization in UVAEM of Inconel 718. Full article

Background: The integration of additive manufacturing (AM) into digital dentistry has extended 3D printing beyond auxiliary applications toward the fabrication of definitive restorations, yet the evidence remains dispersed across diverse materials and technologies. This scoping review aimed to map the available evidence on 3D-printed resin- and ceramic-based materials for definitive tooth-supported restorations, including crowns, fixed dental prostheses, endocrowns, veneers, overlays, and onlays. Methods: The review followed the JBI framework and reported according to PRISMA-ScR. MEDLINE, Embase, and Scopus were searched from inception to April 2026. Two reviewers screened records independently against predefined eligibility criteria, and data were extracted using a piloted charting form capturing study design, materials, additive manufacturing technology, restoration type, and evaluated outcomes. Given the anticipated heterogeneity, extracted data were synthesised descriptively and mapped narratively rather than pooled statistically; 111 studies met the inclusion criteria. Results: The evidence was predominantly in vitro (105 studies), with only six clinical studies, including one randomised controlled trial. Research concentrated on single crowns, zirconia and ceramic-filled/methacrylate-based resins, and vat-photopolymerization technologies. Additively manufactured restorations were frequently reported as comparable to milled controls in dimensional accuracy, marginal and internal fit, and fracture resistance, with values generally falling within the clinically accepted thresholds defined by the primary studies; reported outcomes were most consistent for printed zirconia, whereas printed resins were more often limited by lower strength and colour instability. Outcomes were strongly influenced by processing parameters, underscoring the need for workflow standardisation. Conclusions: The current evidence supports the technical feasibility of 3D-printed definitive restorations more strongly than their long-term clinical durability, highlighting a need for long-term clinical trials. Full article

The gut microbiota and its metabolic functions are critical for intestinal homeostasis, but their integrated responses to diarrhea remain poorly understood in non-model mammals, such as the complex-toothed flying squirrel (Trogopterus xanthipes). Here, we collected fecal samples from six captive animals with diarrhea and six healthy controls; the diarrheal animals had been provided with moldy corn, but mycotoxin levels were not measured. Fecal microbiota was profiled by full-length 16S rRNA sequencing and untargeted metabolomics with integrative analyses. Diarrheal animals showed significantly decreased fecal microbial alpha-diversity and distinct community separation. LEfSe analysis identified Lawsonia intracellularis and Streptococcus macedonicus as the most enriched taxa in the diarrhea group. Untargeted metabolomics revealed 2216 differential metabolites (1931 downregulated), primarily enriched in steroid hormone biosynthesis, arachidonic acid metabolism, and bile secretion pathways. Procrustes and Mantel tests confirmed significant microbiome–metabolome concordance (M² = 0.422, p < 0.001). Spearman correlation networks showed that L. intracellularis was positively correlated with multiple differential metabolites, while S. macedonicus exhibited predominantly negative correlations. These findings suggest that diarrhea in T. xanthipes may be associated with moldy corn exposure and is accompanied by gut dysbiosis and metabolic disturbances. L. intracellularis and S. macedonicus may be associated with disease progression through pathways linked to lipid and bile acid metabolism and inflammation. This study provides novel microbial–metabolic insights into diarrhea in a medicinal mammal, supporting disease prevention and healthy breeding. Full article

Fluoride remains the keystone of evidence-based caries prevention by stabilizing the mineral balance at the tooth–biofilm–saliva interface. Contemporary understanding emphasizes a predominantly post-eruptive, topical mode of action where fluoride inhibits demineralization and accelerates remineralization. This interfacial catalysis is reinforced by pH-responsive calcium-fluoride-like reservoirs that release fluoride during acid challenges. While community water fluoridation confers population-level reductions, the most effective approach is sustaining low-level fluoride in the biofilm environment. Evidence confirms that toothpastes with 1000–1500 ppm fluoride provide a dose–response benefit in children, while 5000 ppm concentrations are indicated for high-risk scenarios such as root caries and xerostomia. Beyond physicochemical effects, fluoride modulates the oral microbiome by inhibiting bacterial enzymes and proton pumps, shifting community function toward a health-associated state without reducing overall diversity. In restorative dentistry, glass ionomer cements offer superior preventive effects against secondary caries compared to amalgam; however, marginal integrity, adhesive performance, and clinical technique, rather than fluoride release alone, remain the primary determinants of success. Despite well-known risks associated with high systemic intake, such as fluorosis, current evidence does not indicate genotoxic or adverse microbiome effects in humans from routine topical use of standard fluoride products at recommended preventive concentrations. Overall, fluoride’s cariostatic value rests on frequent, low-level exposures that maintain tissues in a repair-favoring state. Full article

Objective: This umbrella review aimed to evaluate the strength and consistency of evidence linking genetic variants to dental caries susceptibility. Methods: An umbrella review was conducted, following PRISMA 2020 guidelines. A comprehensive literature search was performed across six databases. Eligibility criteria included systematic reviews and meta-analyses of human subjects. Study selection, data extraction, and methodological quality assessment were performed systematically, with quality evaluated using the AMSTAR-2 tool. Multilevel meta-analyses were conducted to assess variant-specific and grouped genetic effects. Results: The search identified 29 eligible systematic reviews and meta-analyses for inclusion. The multilevel meta-analysis showed statistically significant associations for polymorphisms in TAS2R38 rs713598 (OR = 0.26, 95% CI: 0.09–0.73) and VDR Cdx-2 rs11568820 (OR = 0.66, 95% CI: 0.46–0.95), both indicating lower odds of dental caries, while MBL2 rs1800450 was associated with increased odds (OR = 1.48, 95% CI: 1.03–2.14). However, pooled effects across the main gene categories, including tooth development and mineralization, salivary composition and function, immune and inflammatory response, taste perception, and signaling, were not statistically significant. Findings were heterogeneous across studies. Conclusions: Current evidence on the association between genetic variants and dental caries susceptibility remains limited and inconsistent, providing insufficient support for the use of genetic markers in risk assessment or personalized prevention. The significant single-nucleotide polymorphism (SNP) associations identified in this review are hypothesis-generating and require validation in larger and more diverse populations using standardized caries definitions and gene–environment approaches. Full article

Background: Tongue diagnosis is a fundamental diagnostic method in traditional medicine. Studies restricted to single ethnic groups may introduce bias and limit the clinical applicability of digital tongue diagnosis across diverse populations. Objectives: This study examined differences in tongue image features between Japanese and Brazilian (Caucasian ancestry) participants using digital tongue diagnosis technology and explored potential influencing factors. Methods: Tongue images were collected from 143 Japanese and 116 Brazilian participants attending traditional medicine clinics in Japan and Brazil. An independently developed tongue image analysis system (TIAS) was employed to extract shape, texture (gray level co-occurrence matrix), color (L*a*b color space), and deep-learning derived features (crack, prickle, tooth-mark, peel, greasy coating, stasis). Statistical analyses and machine learning models with SHAP explainability were used to compare features and identify key classification parameters. Results: Significant inter-group differences were observed in tongue shape, texture parameters (particularly at the root and tip), color parameters (especially middle-a-mean, middle-b-mean, tip-a-mean, and tip-b-mean), and deep features. The Japanese group showed a markedly higher prevalence of greasy coating (72.03% vs. 41.38%, p < 0.001) and stasis. Machine learning analysis revealed that the b value in the middle region of the tongue (middle-b-mean) contributed most strongly to the classification of greasy coating. Conclusions: The digital tongue image analysis system enables accurate and objective quantification of tongue features. Pronounced ethnic differences exist, particularly in the distribution of greasy coating. The middle-b-mean has the greatest impact on greasy coating classification. These findings underscore the importance of considering ethnic background when developing digital tongue diagnosis systems. Full article

Background and Clinical Significance: Dental trauma presents a considerable challenge for clinicians due to the diverse and complex effects on teeth. Effective management often requires the collaboration of multiple specialists, including endodontists and orthodontists. Case Presentation: This case report presents the interdisciplinary management of a complex dental trauma case involving three permanent maxillary anterior teeth. Unlike most reports of dental trauma, this case includes complete pre-trauma diagnostic records, providing valuable baseline information for treatment planning and outcome assessment. A 15-year-old female patient was examined in the orthodontic clinic, with comprehensive diagnostic records being obtained at the initial visit. Before the commencement of active orthodontic therapy, the patient experienced an extraoral traumatic incident. Clinical and radiographic assessment revealed concussion and traumatic mobility of the upper right canine, intrusive luxation of the upper right lateral incisor and extrusive luxation with increased mobility of the upper right central incisor. Taking into consideration treatment alternatives, an orthodontic–endodontic approach was preferred. Conclusions: The successful management of complex dental trauma affecting multiple permanent teeth requires interdisciplinary collaboration. The clinical significance lies in the potential long-term consequences on both tooth function and aesthetics, which can impact patient well-being. Full article

The range of possible inflammatory changes in the oral cavity and in the maxillary and mandibular bones may present with diverse patterns and characteristics in both clinical and radiological evaluation. In most cases, a standard radiological examination, such as dental panoramic radiograph (DPR), has significant limitations in assessing early or complex bone changes associated with chronic bone inflammation. Advanced imaging with multidetector computed tomography or cone-beam computed tomography (MDCT or CBCT) can improve lesion characterization and surgical planning when a detailed evaluation of tooth-bearing structures, tooth apices, cortical plates, and cancellous bone is required. Such imaging allows more detailed assessment of alterations in medullary bone morphology and architecture, as well as identification of possible periosteal reactions adjacent to chronic bone inflammation. Osteomyelitis of the jaws comprises a heterogeneous group of inflammatory bone disorders characterized by variable clinical presentations and a broad spectrum of radiological appearances. Depending on disease chronicity, host factors, and microbial burden, mandibular osteomyelitis may mimic odontogenic tumors, fibro-osseous lesions, or malignant bone pathologies. Quite often, dental treatment affects bone status and condition, leading to unwanted events such as bone inflammation. Imaging plays a central role in diagnosis; however, radiographic findings are often nonspecific, particularly in early or chronic stages. Each case of osteomyelitis underscores the importance of correlating imaging findings with clinical history and highlights the role of repeated imaging in distinguishing inflammatory bone disease from aggressive jaw lesions. This study aims to characterize diverse patterns of chronic mandibular osteomyelitis associated with various prior treatment modalities using CBCT. By presenting a series of illustrative cases from heterogeneous clinical settings, the authors highlight the nonspecific radiographic features and diagnostic challenges inherent in chronic bone inflammation. The focus remains on the interpretation of complex imaging findings rather than a comparative analysis of technical protocols. Full article

To address the issues of sealing leakage and airflow-induced vibration in high-speed turbomachinery, a conical straight-tooth annular clearance sealed hybrid aerostatic/aerodynamic bearing is investigated. A three-dimensional CFD model is established to study the effects of radial clearance height, inlet pressure, rotor speed, and eccentricity on pressure distribution, velocity distribution, and leakage rate. The results show that leakage exhibits a strong positive nonlinear correlation with clearance height and inlet pressure, following a power-law or polynomial relationship, while rotor speed and eccentricity exert negligible effects (less than 5%). The underlying mechanisms are identified as the kinetic energy diversion caused by circumferential shear and the mutual cancelation of throttling and backflow effects. Increasing the gap height enhances leakage by expanding the hydraulic diameter and strengthening vortex disturbance; increasing inlet pressure promotes leakage by elevating the driving force and intensifying local flow separation. Full article

This study investigates the stress–strain state of rocks subjected to the impact of penetrators with diverse configurations, employing numerical simulations in the ANSYS Workbench Static Structural module. The research focuses on the interaction between roller cone drill bit teeth and rock formations during blast hole drilling. Through finite element modeling using a linear elastic constitutive model, the influence of penetrator geometry, position relative to borehole walls, angle of attack, and distance to open surfaces on rock fracture parameters is analyzed. Key quantitative findings include: the relative breaking force near the borehole wall reaches 2.8 for soft rocks (siltstones) with a 10 mm tooth diameter, and decreases to approximately 1.0 at a distance of 1.5d from the wall; the optimal angle of attack ranges from 60° to 90° depending on rock hardness; and the proximity to a free surface reduces fracture resistance to as low as 0.23 of the baseline value. Six sets of parabolic regression equations (R² > 0.95) are derived for relative breaking forces across three rock hardness groups and two tooth diameters. Optimal parameters for tooth placement, borehole bottom shapes, and operational conditions are proposed. Implementation of the recommended parameters is estimated to increase drilling efficiency by 10–20% and extend tool service life by 15–30%. The findings provide a scientific foundation for designing advanced roller cone drill bits suitable for rocks with Protodyakonov hardness indices ranging from f = 5 to f = 18. Full article

Bornaviruses are neurotropic, negative-sense RNA viruses with zoonotic potential, notably Borna disease virus 1 (BoDV-1) and variegated squirrel bornavirus 1 (VSBV-1). BoDV-1 is endemic in certain regions of Central Europe and maintained in bicolored white-toothed shrews, but its presence in Croatia has not been investigated. Given Croatia’s diverse biogeography and the prevalence of rodent-borne diseases, this study aimed to investigate the presence of orthobornaviruses in wild canids and mustelids. Brain samples from red foxes (Vulpes vulpes), golden jackals (Canis aureus moreoticus), wolves (Canis lupus), martens (Martes martes) and badgers (Meles meles) were analysed using pan-bornavirus RT-PCR. Despite successful RNA extraction and internal control amplification, bornavirus RNA was not detected in any of the 860 animal samples tested. Although no orthobornavirus RNA was detected, the results still provide valuable information: bornavirus infections appear to be absent or extremely rare in Croatian wild canids and mustelids. By excluding these species as current potential reservoir hosts, this study helps to refine the geographical extent of bornavirus endemicity and emphasises the importance of continuous One Health surveillance in regions with favourable ecological conditions for zoonotic spillover. Full article

Background/Objectives: Amelogenesis imperfecta (AI) is a heterogeneous group of rare hereditary conditions mainly affecting the quantity and/or quality of tooth enamel. Its phenotypic expression is diverse, as is the mutational spectrum of the AI-causing genes and mutations. Integrins are cell-surface receptors that mediate adhesion between cells and between cells and the extracellular matrix. Among these, mutations in integrin αvβ6 have been shown to cause AI; however, phenotypic variation exists between the knockout mouse model and human cases, as well as among different human AI families. Methods: We recruited AI families and performed mutational analysis using whole exome sequencing. Results: We identified compound heterozygous ITGB6 mutations in two families. In Family 1, a paternally transmitted nonsense mutation (NM_000888.5: c.1060C>T, p.(Gln354*)) and a maternally transmitted missense mutation (NM_000888.5: c.2312A>G, p.(Asn771Ser)) were identified; in Family 2, a paternal missense mutation (NM_000888.5: c.1693T>C, p.(Cys565Arg)) and a maternal frameshift mutation (NM_000888.5: c.2091delC, p.(Asn698Metfs*13)) were identified, each causing AI in the respective proband. Both probands exhibited generalized hypoplastic and hypomineralized AI, but no other extraoral symptoms. Conclusions: This report will not only expand the known mutational spectrum of the ITGB6 gene but also provide evidence for the genotype–phenotype correlations, thereby improving our understanding of the functional role of ITGB6 during amelogenesis. Full article