Search Results (467)

Dental caries remains the most prevalent chronic disease worldwide, yet early enamel lesions are reversible if managed with appropriate remineralizing agents. This narrative review synthesizes current evidence on remineralizing agents, their mechanisms of action, and clinical applications, with a focus on dental materials used in preventive and minimally invasive dentistry. Traditional fluoride-based approaches enhance remineralization through fluorapatite formation; however, their effectiveness is limited when calcium and phosphate bioavailability is insufficient. Biomimetic agents, including casein phosphopeptide–amorphous calcium phosphate (CPP-ACP), bioactive glasses, tricalcium phosphate, and nano-hydroxyapatite, provide these bioavailable ions and demonstrate superior performance under challenging clinical conditions. Emerging therapies such as probiotics, photodynamic therapy, and laser-assisted mineralization show promise but require further clinical validation. Based on the primary mechanism of action, an original classification of remineralizing agents is proposed, grouping them into fluoride-based agents, calcium-phosphate systems, nanotechnology-based systems, biofilm modifiers, biomimetic and emerging systems, and adjunctive antimicrobial therapies. The review concludes that bioavailable calcium represents a critical limiting factor in remineralization under certain conditions, and that combination protocols incorporating multiple remineralizing agents, tailored to individual patient risk profiles, achieve superior outcomes compared to single-agent approaches. Clinicians are encouraged to adopt minimally invasive, patient-tailored remineralization strategies that arrest lesions before cavitation, preserving natural tooth structure and reducing the lifelong restorative burden. Full article

The term “periapical lesion” refers to a pathological change in the tissues surrounding the apex of a tooth root, defined by its anatomical location rather than a distinct disease entity. Periapical lesions may be of endodontic origin, most commonly resulting from microbial infection of the root canal system following pulp necrosis due to caries, trauma, or other insults, or of non-endodontic origin, such as developmental cysts, benign and malignant odontogenic and non-odontogenic tumors, and fibro-osseous lesions. Accurate diagnosis requires a systematic approach combining patient history, clinical examination, pulp vitality testing, and radiographic assessment; histopathological evaluation is indicated when clinical and radiographic findings are inconsistent or suspicious. The pathophysiology of these lesions involves dynamic interactions between root canal microorganisms and the host immune-inflammatory response. The primary management for endodontic periapical lesions is root canal treatment, which aims to reduce or eliminate root canal microorganisms through mechanical debridement and chemical disinfection. Persistent or extensive endodontic lesions and non-endodontic lesions may require surgical intervention. Molecular and inflammatory biomarkers have been investigated as adjunctive tools for assessing disease activity and prognosis; however, these remain largely investigational and are not yet part of routine clinical practice. Future developments in artificial intelligence, advanced imaging, molecular diagnostics, and personalized therapies may enhance the diagnosis and management of periapical lesions, although further clinical validation is required. Full article

Background/Objectives: In 2018, a classification system for periodontal and peri-implant diseases and conditions defined an endo-periodontal lesion (EPL) as a pathological communication between the endodontic and periodontal tissues of a given tooth. As the evidence to define the etiology, diagnosis, prognosis and treatment was considered limited, a cross-sectional study was carried out to evaluate its prevalence in a population treated at the Periodontics Department of Faculty of Dentistry of University of Buenos Aires (FOUBA). The primary objective was to evaluate the prevalence of EPL. The secondary objective was to identify potential risk indicators associated with their prevalence. Methods: Patients referred for first time to the Periodontics Department of FOUBA during April to June 2025 were consecutively selected. Clinical and radiographic examination was carried out. Categorical outcomes were described using proportions. The crude association between the prevalence of EPL and each of the recorded factors was determined by means of the chi-square test and a logistic regression analysis. Results: A total of 182 participants (128 women and 54 men) with a mean age of 50.8 (standard deviation = 15.6) years were included. The prevalence of participants with EPL was 14.8%. The average was 1.7 teeth per participant with a minimum of 1 tooth and a maximum of 5 teeth. In total, 85.2% of participants with EPL had stage III–IV generalized periodontitis, grade B or C. The logistic regression analysis identified periodontitis stage III–IV (OR = 5.9; 95% Confidence interval [1.9: 18.9] (p = 0.003)) as a potential risk indicator for EPL. Conclusions: The prevalence of participants with EPL in a teaching hospital of the University of Buenos Aires was 14.8%. EPL was more frequently found in participants with periodontitis stage III–IV. Periodontitis stage III–IV was considered a potential risk indicator of EPL. Full article

Background/Objectives: Dynamic navigation and robot-assisted implant workflows depend on robust intraoral perception. Marker-based tracking introduces workflow complexity and is sensitive to occlusions, motivating markerless alternatives. This study evaluates whether a single-stage YOLO instance segmentation model (YOLO-seg) can provide a practical markerless perception layer for dental navigation, combining accurate per-tooth delineation with low, predictable inference latency. Methods: YOLO-seg was trained end to end on an intraoral RGB corpus of 400 training, 20 validation, and 100 testing images, combining a public source and a partner-hospital in-house set. A two-stage YOLO + SAM baseline was implemented for comparison. Segmentation quality was evaluated on a 50-image held-out clinical test set at three complementary levels (per-instance matching, per-class union, and global union), with paired Wilcoxon signed-rank tests, Cliff’s delta effect sizes, and 95% bootstrap confidence intervals. Runtime was assessed under matched inference-only and end-to-end conditions on N = 100 frames at a 640 × 640 resolution on an NVIDIA RTX A2000 GPU. Results: YOLO-seg significantly outperformed YOLO + SAM across all primary metrics, with very large effect sizes (Cliff’s delta: 0.76–0.94; Wilcoxon p < 10⁻⁸ on every metric except precision at IoU ≥ 0.5). YOLO-seg reached AP₅₀ = 0.716 and recall = 0.973 versus 0.383 and 0.398 for YOLO + SAM. Under matched inference-only timing, YOLO-seg ran at 27.08 ms per frame (36.9 FPS) versus 1302.78 ms (0.77 FPS), an approximately 48-fold latency gap intrinsic to the two-stage forward pass. Conclusions: YOLO-seg shows strong potential as a 2D perception module for dental navigation, balancing per-instance segmentation fidelity with real-time feasibility under the tested conditions. These results support its use as a 2D perception front-end for future integration with stereo-based 3D reconstruction and robot-assisted navigation; 3D registration accuracy, implant-placement error, and robotic execution remain outside the scope of the present study. Full article

Objectives: This study aimed to identify the oral health conditions of homeless individuals in Rome, the most frequently required dental treatments, and to describe a standardized, replicable clinical protocol tailored to the specific needs and access barriers of this vulnerable population. Methods: Five hundred homeless individuals received comprehensive dental examinations at the Primary Care Services of the Dicastery for the Charity Services (Vatican City) between September 2023 and January 2026. Clinical assessments included oral hygiene status, periodontal health, caries prevalence, and degree of edentulism. Treatment interventions were programmed by scheduling subsequent appointments. For patients requiring prosthetic rehabilitation, treatment was sequenced into distinct steps: preparatory treatments (hygiene, extractions, conservative procedures), impression taking, prosthesis try-in, and delivery. Results: Oral health assessment revealed poor or absent hygiene (85.4%), high DMFT scores (63.0%), and root residues (22.4%). Periodontal disease affected 94.0% of participants (gingivitis 73.0%, periodontitis 21.0%). Tooth loss patterns included partial edentulism (12.0%) and complete edentulism (24.0%). A total of 440 appointments were scheduled, with an attendance rate of 78.4%. Prosthetic rehabilitation was completed in 150 patients: 50 received partial dentures (33.3%) and 100 complete dentures (66.7%). Conclusions: The examined homeless individuals experienced severe oral health deterioration characterized by extensive tooth loss and advanced periodontal disease. A substantial prosthetic rehabilitation was needed in this sample. The proposed sequential treatment protocol demonstrated high feasibility and patient adherence in this vulnerable population. Comprehensive dental services that address both immediate emergency needs and long-term rehabilitative care are crucial for improving oral health-related quality of life and facilitating social reintegration. Patient-reported outcomes indicated meaningful improvements in digestive function, aesthetic satisfaction, and employment opportunities following prosthetic rehabilitation. Full article

Preservation of dentition remains the primary goal of equine dentistry; however, cheek tooth extraction is required in cases of severe dental pathology. Following tooth extraction, management of the post-extraction alveolus remains a significant clinical challenge due to its large size and susceptibility to contamination with feed material and bacteria. To mitigate these risks, alveolar plugs are commonly used to protect the alveolus, stabilize the blood clot, and support granulation tissue formation. This review summarizes the current case reports and research articles regarding the use of alveolar plugs following equine cheek tooth extraction, with a focus on packing materials, post-extraction management strategies, complications, and clinical outcomes. Reported packing materials include polymethyl methacrylate (PMMA), plaster of Paris (PoP), dental wax, gauze swabs, and polyvinyl siloxane (PVS). Each material has unique advantages and disadvantages, which are summarized in this review. The choice of plug material and its management protocol should be individualized for each case, as it depends on alveolar depth, tooth location, extraction method, and the presence of complications. Although standardized protocols for equine alveolar plug management have not yet been established, it may be suggested that any of the currently described packing materials can be used following routine tooth extractions. For marginally positioned teeth, gauze swab plugs may be more favorable, although they may not be the optimal choice in older horses. Regardless of whether the extraction is routine or complicated, alveolar inspection at 7–14-day intervals may be recommended. However, specific recommendations regarding alveolar inspection intervals and detailed management strategies require further research. Full article

Background/Objectives: Fixed orthodontic appliances interfere with oral hygiene and contribute to plaque retention, gingival inflammation and demineralization of enamel. Standard techniques for keeping oral hygiene (tooth brushing, mouthwashes, dental floss, interdental brush, etc.) are not sufficiently effective. The aim of this study was to investigate the effectiveness, safety, tolerability, and influence on quality of life of an electrolysis device being added to standard techniques of oral hygiene in orthodontic patients, compared to standard methods only. Methods: This 6-month study was designed as an observational prospective-cohort investigation. Primary outcomes of the study were indices of gingival inflammation and bleeding, dental plaque indices, the number of white spots on enamel, and safety (incidence of adverse events). Secondary outcomes were quality of life and overall costs of keeping oral hygiene. Results: The addition of the Neo Pill device to standard oral hygiene maintenance measures was associated with improvements in oral health indices after 6 months; however, given the non-randomized, preference-driven design, these findings reflect an association and should not be interpreted as evidence of causal efficacy. After 6 months, the primary outcomes of the study were significantly reduced compared to the application of only standard oral hygiene methods (from 21 to 55% reduction); the quality of life related to oral health was higher (for 14%), the tolerability of maintaining oral hygiene was the same as with standard measures and the costs of maintaining oral hygiene consumables were lower in the Neo Pill group (median difference 30%); however, this figure excludes the acquisition cost of the device itself, which was donated to all participants by the manufacturer, and the 95% confidence interval for this difference includes zero. Conclusions: The addition of an electrolysis device to standard oral hygiene maintenance measures in people wearing fixed orthodontic appliances was associated with improvements in gingival inflammation, papillary bleeding, and dental plaque indices—outcomes measured with established clinical instruments. Apparent reductions in white-spot lesion counts were also observed but should be considered exploratory given the absence of calibrated or blinded lesion assessment. These findings are preliminary and do not establish causal efficacy. Full article

Background: Elderly patients often experience difficulty adapting to occlusal reconstruction. Therefore, accurate bite registration is mandatory to ensure precise transfer of the established maxillomandibular relationship to the definitive prosthesis. However, conventional bite registration methods may compromise reproducibility because of deformation of registration materials and instability of mucosa-supported record bases. Methods: A 65-year-old woman with the primary complaints of unstable occlusion and difficulty in mastication underwent occlusal reconstruction. After occlusal stabilization using provisional crowns, bridges, and removable partial dentures, definitive impressions were made with and without the provisional restorations. The casts were scanned, and the digital datasets were superimposed to reproduce the established occlusal morphology of the provisional restorations. This occlusal morphology was used to design a tooth-supported computer-aided design–computer-aided manufacturing (CAD–CAM)-fabricated milled provisional restoration. Following intraoral verification of occlusal stability, the milled provisional restoration served as a mounting guide for the working casts on an articulator. Definitive crowns, bridges, and removable partial dentures were then fabricated. Results: Following comprehensive prosthodontic rehabilitation with definitive prostheses, occlusal stability and masticatory function improved, and the patient was satisfied with the functional outcomes of treatment. Conclusions: A tooth-supported CAD–CAM-fabricated milled provisional restoration used as a bite registration device enables potentially more consistent transfer of the maxillomandibular relationship while avoiding mucosal displacement and material deformation. This technique, which integrates digital and conventional workflows, may provide a new option for addressing adaptation challenges in occlusal reconstruction. Full article

Introduction: Oral health in early childhood is essential. Parents, as the primary caregivers, must possess basic knowledge to achieve optimal oral health status. Objectives: The study aims to assess parents’ knowledge and perspectives on early childhood oral health and to evaluate how nationality and educational attainment influence their preventive habits and dental priorities within a nursery and primary school in the province of Huelva (Spain). Materials and Methods: The sample consisted of 129 parents of children aged 3, 4, and 5 years from the aforementioned educational center. A modified questionnaire, validated by experts in the field, was used as the assessment tool. Results: Nationality and education were key determinants of oral health literacy. Spanish-born guardians reported significantly higher dental attendance for their children compared to foreign-born guardians (97.7% vs. 84.2%; p = 0.030). A profound cultural gap was observed in caries etiology: 71.1% of foreign-born respondents attributed caries to “infections or heredity,” while 98.4% of Spanish-born respondents correctly identified behavioral factors (p < 0.001). Regarding educational attainment, 75% of the high-education group prioritized functional health (posterior sector) compared to only 26.3% in the low-education group (p < 0.001). Additionally, a non-linear gap was found in knowledge of primary tooth complications, with the medium-education group showing the lowest awareness (34.8%; p = 0.047). Full article

Background/Objectives: Mastication is a complex sensorimotor function involving coordination between the brainstem central pattern generator and supraspinal systems, particularly the primary motor cortex (M1). Evidence suggests a link between masticatory activity and corticomotor plasticity, but findings remain fragmented. This scoping review aimed to synthesise the human evidence on the relationships among mastication, tooth loss, dental rehabilitation, ageing, and corticomotor plasticity, with emphasis on M1 mechanisms. Methods: Following PRISMA-ScR guidelines, systematic searches were conducted in MEDLINE/PubMed, Scopus, and Web of Science using terms related to mastication, neuroplasticity, motor cortex, ageing, and rehabilitation. Eligible studies included human experimental, clinical, and observational research employing neuroimaging or neurophysiological methods. Data were extracted and synthesised using a Population–Concept–Context framework across eight conceptual domains. Results: Twenty-two heterogeneous studies (fMRI, TMS, EMG, psychophysical, histological) were included. Mastication consistently activated distributed sensorimotor networks, including M1 and the primary somatosensory cortex (S1). Peripheral sensory input and dental mechanoreception were linked to structural and functional adaptations. Corticomotor excitability was modulated by chewing, oral-motor learning, and rehabilitative interventions. Ageing was associated with altered but preserved cortical responsiveness. Associations between mastication and cognition were reported, though largely cross-sectional. Overall, findings suggested a relationship linking peripheral input, sensorimotor integration, and corticomotor plasticity, but methodological variability limited causal inference. Conclusions: Mastication is linked to modifiable corticomotor activity and supports experience-dependent neuroplasticity. However, the evidence remains largely associative and methodologically heterogeneous. Neural adaptations appear to be preserved with ageing but are influenced by systemic and environmental factors. Longitudinal, multimodal research is needed to clarify the mechanisms, causality, and clinical relevance, particularly in rehabilitation contexts. Full article

The aim of the study was to evaluate the immediate and aged shear bond strength (SBS) of a dual-cured and a light-cured universal adhesive to primary and permanent dentin. Twenty caries-free primary molars and twenty permanent third molars were selected and sectioned to expose mid-coronal dentin. Specimens were assigned to four groups (n = 10) according to dentition type and adhesive agent used: Group 1—primary teeth/Scotchbond Universal; Group 2—permanent teeth/Scotchbond Universal; Group 3—primary teeth/Futurabond U; and Group 4—permanent teeth/Futurabond U. Two resin micro-rods were fabricated and bonded with the same adhesive on each specimen. The SBS test was applied after 24 h (first micro-rod) and after thermocycling (second micro-rod). Failure modes were assessed under an optical microscope and scanning electron microscopy. Shear bond strength was significantly higher in permanent teeth than in primary teeth (p < 0.001). No statistically significant differences were found between the two adhesives (p = 0.194). Adhesive failures predominated across all groups. Both adhesives exhibited comparable SBS to primary and permanent dentin. These findings support the suitability of both universal adhesives for the restoration of primary and permanent teeth, though long-term clinical studies are warranted. Full article

Autologous tooth-derived grafts are increasingly being investigated for bone regeneration, as dentin shares with bone a mineral phase and an organic matrix rich in type I collagen and non-collagenous proteins. Deciduous teeth are particularly attractive as biomaterials because they are easily obtained after physiological exfoliation, without additional surgical harvesting or donor-site morbidity and may expose a protein-rich matrix after processing. Whether deciduous teeth retain a biologic advantage after prolonged dry storage remains poorly documented. This proof-of-concept ex vivo and in vitro study compared pooled deciduous teeth from six different donors (exfoliated at least 10 years before the experiment and stored dry at room temperature conditions) with six freshly extracted third molars. The teeth were ground using a dedicated device, and conditioned supernatants were collected at 72 h (T1) and 28 days (T2). Osteocalcin, osteonectin, and BMP-2 were quantified by ELISA, and T1 supernatants were applied to human primary osteoblasts to assess the osteogenic response using qRT-PCR and immunofluorescence. Deciduous teeth-conditioned supernatants showed higher osteocalcin and osteonectin release than permanent teeth at both time points, whereas BMP-2 levels were comparable, though with higher values in deciduous samples. In osteoblasts, deciduous teeth-conditioned supernatants induced enhanced osteogenic responses, including greater activation of Collagen I, Osterix, RUNX-2, Osteocalcin, BMP-2 genes, and higher expression of bone-related proteins. Within the limits of this exploratory study, dry-stored deciduous teeth preserved a biologically active dentin matrix and showed a more favorable osteogenic profile than freshly extracted permanent teeth, supporting further investigation into standardized storage protocols and their potential use in regenerative applications. Full article

Background: Natural compounds such as propolis and chitosan have been investigated for their potential use in dental formulations. Aim: To evaluate the effect of an experimental propolis/chitosan varnish on previously demineralized primary tooth enamel using surface roughness, wear profile, microhardness, and morphological analysis. Design: Primary enamel specimens were allocated to three groups (n = 13): no treatment control (C), Duraphat varnish (DV), and experimental propolis/chitosan varnish (EV). Specimens were first subjected to a demineralizing challenge to produce artificial caries-like lesions. After treatment application, samples underwent seven days of pH cycling. Surface roughness, wear profile, and longitudinal Knoop microhardness were evaluated. Data were analyzed using ANOVA and Tukey’s post hoc test (α = 5%). Results: For wear profile, no significant differences among groups were observed after initial demineralization or after treatment/pH cycling. Post-treatment roughness differed among groups, with DV showing the highest Sa values, whereas C and EV were statistically similar. For microhardness, DV showed the highest EA/DA and EA/CA percentage values and differed significantly from C and EV. The EV group did not differ significantly from the untreated control for wear profile or microhardness. Morphological analysis showed surface irregularities after demineralization and different surface patterns after treatment. Conclusions: Under the conditions of this in vitro study, the experimental propolis/chitosan varnish did not promote remineralization of previously demineralized primary enamel and did not demonstrate superiority over the untreated control. Duraphat varnish showed microhardness values suggestive of partial mineral recovery. Full article

Herringbone gear pairs are critical in high-speed aerospace transmissions, where windage power loss significantly impacts efficiency and thermal management. This study proposes a prediction method that decomposes the total windage loss into five components based on structural features: the tooth, end, circumferential, and relief groove surface losses for both gears, and the meshing extrusion loss. Theoretical models for each component are established to form a complete prediction method using fluid–structure interaction principles. CFD simulations analyze the velocity, pressure, and energy fields around the gear pair, with windage loss integrated via fluid torque on gear surfaces. Results indicate that windage loss escalates rapidly and becomes non-negligible when the driving gear speed exceeds 7000 rpm. The prediction model demonstrates strong agreement with CFD simulations, with a maximum relative error of 13.6%. Analysis reveals that the driving gear contributes the largest share of the total gear pair loss, with meshing extrusion accounting for 20.1–23.6%. For a single herringbone gear, the tooth surface is the primary source of loss (~83%), followed by the end surface (~8%), while relief groove and circumferential losses remain below 10%. This research provides a validated theoretical foundation for optimizing efficiency and thermal control in high-speed aerospace gear systems. Full article

The model is based on the periodic translational symmetry of regular saw-toothed joint surfaces and reveals the time-dependent breaking of this symmetry under hydro-mechanical coupling through the introduction of damage evolution. Traditional creep models typically rely on static constants, which fail to capture the nonlinear, time-dependent degradation of rock under complex conditions. To address this, this paper proposes a novel nonlinear shear creep model for regular saw-toothed joint surfaces under hydro-mechanical coupling. First, a calculation method for effective shear stress is established, accounting for normal stress, asperity height, and water pressure. Next, traditional static parameters are transformed into dynamic variables to accurately model the primary and steady-state creep stages. Finally, a plastic damage element is introduced to simulate the accelerated creep stage, revealing that damage accumulates with time and is exacerbated by higher seepage pressure. By integrating early-stage viscoelastic and late-stage viscoplastic characteristics, this model captures the complete nonlinear shear creep process, providing a robust theoretical basis for long-term stability evaluations. Full article