Search Results (72)

Objective: This is the first population-based study to separately examine whether preventive and treatment dental visits modify the association between stressful life events and toothache. Psychological stress may alter health-seeking behaviors and pain perception, potentially leading to symptom-driven rather than preventive dental visits. Methods: Cross-sectional data were obtained and analyzed from the 2019 wave of the Japan Gerontological Evaluation Study (JAGES), including 19,314 community-dwelling adults aged 65 years and older. Poisson regression analyses were conducted to examine the associations between stressful life events, dental visit history, and self-reported toothache. Results: Higher stressful life events were associated with greater toothache prevalence (PR = 1.189; 95% CI: 1.117–1.264). Preventive dental visits within the past six months were linked to the lowest risk, whereas recent treatment visits were associated with higher risk. Conclusion: Promoting regular preventive dental visits, particularly among individuals under high stress, may help reduce the likelihood of experiencing toothache among older adults. Full article

Aim: This study aimed to assess self-reported oral and orofacial health, hygiene habits, and oral health knowledge among Croatian athletes, and to determine factors influencing that knowledge. Differences between contact and non-contact sports, as well as the occurrence of dental trauma and temporomandibular joint (TMJ) symptoms, were also examined. Methods: A cross-sectional, questionnaire-based study was conducted among 1007 athletes (56% male, 44% female) aged 18–42 years, recruited through national sports federations and university sports clubs. The instrument comprised 85 items divided into five domains: sociodemographic data, oral hygiene habits, self-assessed oral health, TMJ symptoms, and oral health knowledge. Data were analysed using descriptive statistics, Chi-square and Fisher’s exact tests, and generalised linear modelling (p < 0.05). Results: Athletes demonstrated moderate oral health knowledge (mean score 11.3 ± 4.4/18). While 92.2% recognised that poor oral hygiene leads to caries and periodontitis, only 52.4% correctly identified the ideal time to replant an avulsed tooth. Female participants, older age groups, and those with higher education had significantly better knowledge (p ≤ 0.05). Recreational athletes scored higher than amateurs (p = 0.002), and those with prior dental trauma experience also showed greater awareness (p = 0.028). No significant difference was found between contact and non-contact sports (p = 0.287). Despite good brushing habits (86.9% brushed twice daily), only 25.4% regularly used dental floss or interdental brushes. A small proportion of athletes reported symptoms related to temporomandibular joint function, most commonly joint clicking (18.2%), tooth wear (13.4%), and nocturnal bruxism (14.3%). There were no significant differences between contact and non-contact sports, except for muscle stiffness near the temples (p = 0.024) and daytime or stress-related teeth grinding (p = 0.013 and p = 0.018). Conclusions: Croatian athletes demonstrated moderate oral health knowledge and satisfactory hygiene habits, but preventive practices remain inadequate. Education level, gender, and previous dental trauma were key determinants of knowledge. Systematic preventive programmes and targeted education are necessary to improve oral health awareness in sports populations. Full article

This study aimed to analyze the biomechanics of three abutment systems with distinct retention mechanisms and their impact on the implant–abutment interface (IAI). The finite element analysis method was used to model maxillary three-unit restorations with conventional cement-retained abutment (CRA), multi-unit abutment (MUA), and innovative cementless link-retained abutment (LRA) systems. Dental implants were positioned at 0°/0°, 15°/15°, and 25°/25° angulation combinations. Analyses were performed under 400 N vertical and 200 N oblique loading applied at a 45° angulation. The LRA system exhibited lower stress on the implants and abutments under both loading conditions, whereas the CRA system demonstrated the highest stress. In contrast, the maximum principal stresses within the peri-implant bone were the highest in the LRA system under both loading conditions. Despite greater IAI displacement in the molar region, no specific abutment system exhibited distinct superiority under different scenarios. Overall, an increase in implant angulation led to higher stress values across all parameters. The MUA and LRA systems demonstrated reduced stress concentration and more uniform load distribution compared with the CRA system under tilted implant configurations. The findings suggest that the innovative cementless LRA system may serve as a feasible alternative to conventional CRA and MUA systems, exhibiting superior biomechanical performance, particularly compared with the CRA system. Full article

Background/Objectives: Dental training is known for its demanding academic pace, early clinical exposure, and constant performance pressure. These stressors may contribute to behavioral and physical manifestations, including bruxism and temporomandibular disorder (TMD). This study aimed to better understand the multidimensional burden experienced in this educational setting by investigating the relationship between education-related stress, bruxism patterns, and temporomandibular symptoms (TMD-related symptoms) in dental students. Methods: A cross-sectional survey was conducted at the Ankara University Faculty of Dentistry in 2025 and completed by 287 undergraduate dental students. The questionnaire collected sociodemographic information, self-reported bruxism status, TMD-related symptoms via the Fonseca Anamnestic Index (FAI), and education-related stressors using the Dental Environment Stress (DES) scale. Descriptive statistics, group comparisons, and Spearman correlation analyses were conducted. Results: Bruxism was reported by 76% of students and was significantly more common among females (p < 0.05). Students with bruxism demonstrated higher DES (3.34 ± 0.84) and FAI (41.81 ± 20.32) scores compared with those without bruxism (p < 0.001). DES and FAI scores showed a significant positive correlation (r = 0.229, p < 0.001). Stressors related to workload, examinations, limited rest time, clinical uncertainty, patient responsibility, and financial concerns were strongly associated with bruxism, while inconsistent academic feedback emerged as a key distinguishing factor. Conclusions: Education-related stress is closely linked to bruxism and TMD-related symptoms among dental students. Beyond overall stress intensity, the nature of experienced stressors plays a critical role. These findings highlight the importance of supportive learning structures, targeted stress-management strategies, and curriculum-level improvements to promote student wellbeing and resilience. Full article

Peri-implantitis, a common biological complication of dental implants, is characterized by soft-tissue inflammation and progressive bone loss. Oxidative stress is increasingly implicated in its pathogenesis, yet the diagnostic potential of salivary redox biomarkers remains unclear. This study’s objective was to assess the association between salivary malondialdehyde (MDA) and total antioxidant capacity (TAC) and peri-implant disease via a pre-registered, quantitative meta-analysis of previously published studies using predefined statistical criteria. Following a priori PROSPERO registration, we systematically searched PubMed, Scopus, and Web of Science (2004–September 2025), extracted data in duplicate, and pooled effects using random-effects models; certainty of evidence was appraised with GRADE (Grading of Recommendations Assessment, Development and Evaluation) and risk of bias with ROBINS-I (Risk Of Bias In Non-randomized Studies of Interventions)/QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies-2). Twelve studies were included qualitatively: seven (n = 726) contributed to MDA and five (n = 485) to TAC meta-analyses. Peri-implant disease was associated with elevated MDA (SMD = 1.64, 95% CI 1.39–1.88) and reduced TAC (SMD = −1.88, 95% CI −2.17 to −1.58); statistical heterogeneity was not detected, and results were robust to sensitivity and exploratory assay-based subgroup analyses. Salivary MDA and TAC show consistent, large, standardized differences in peri-implant disease; however, observational designs, assay variability, and the absence of validated diagnostic thresholds warrant cautious interpretation and prospective validation before clinical adoption. Full article

Advances in additive manufacturing have accelerated the development of 3D-printed dental resin composites. These materials contain a higher proportion of organic matrix and less filler than light-cured representatives, which may affect their behavior in the oral environment. This study aimed to evaluate the biological and chemical properties of 3D-printed dental resin composites before and after artificial aging, and to compare them with the light-cured representative. Specimens from a light-cured composite (Omnichroma—OMCR) and two 3D-printed composites (GT Temp PRINT—GTPR; SprintRay CROWN—SPRY) were subjected to aging treatments: unaged (T0) or thermocycled for 5000 (T1) and 10,000 cycles (T2). Biological evaluation was performed using MTT assay and Live/Dead cell fluorescence microscopy using human gingival fibroblasts, whereas Raman spectroscopy analysed materials’ structural changes. Materials exhibited good biocompatibility (>70% cell viability), with OMCR displaying greater variability. OMCR was more susceptible to chemical degradation under thermal stresses than both 3D-printed materials. Tested 3D-printed composites can provide comparable or even superior biological and chemical properties compared to light-cured representative, likely due to optimized resin formulations and post-curing protocols that improve polymer network organization and reduce residual monomer release. These findings support the potential of tested 3D-printed composites for manufacturing dental restorations. Full article

Titanium alloys are widely used in orthopedic and dental implants, yet their limited bioactivity and bacterial resistance remain critical challenges. This study aimed to enhance the surface performance of a Ti-13Zr-13Nb alloy through the formation of a porous oxide layer and the application of a bioactive, drug-loaded coating. Porous oxide layers composed of Ti, Zr, and Nb oxides with fluoride incorporation were fabricated using a novel anodizing process. The fluoride-assisted electrochemical mechanism controlling oxide growth was elucidated through SEM and EDS analyses. The anodized surface exhibited reduced microhardness, beneficial for minimizing stress-shielding effects. Subsequently, chitosan–tetracycline composite coatings were produced via EPD and compared with dip-coating method. Characterization by ATR-FTIR, optical microscopy, SEM, and UV-VIS spectroscopy confirmed the formation of uniform, adherent, and moderately porous coatings with sustained drug release when produced by EPD, while dip-coated layers were less homogeneous and released the drug faster. Microhardness testing revealed improved mechanical integrity of EPD coatings. The developed chitosan–tetracycline–oxide layer system provides tunable nano/microgram-scale drug release and enhanced surface functionality, offering promising perspectives for acute and medium-term regenerative and antibacterial biomedical applications. Full article

Background: Sleep disorders, particularly insomnia, represent a significant health concern in medical education. Neuroticism, characterized by emotional instability and stress reactivity, shows cross-sectional associations with sleep disturbances in healthcare trainees. Limited research examines these relationships among South Asian medical students. This cross-sectional study investigated insomnia symptom prevalence, personality correlates, and environmental factors among Pakistani medical students. Methods: We conducted a cross-sectional study among 364 undergraduate medical and dental students in Peshawar, Pakistan (June–November 2024). Data collection occurred during examination months. Data collection employed validated instruments: the Insomnia Severity Index (ISI) and the NEO Five-Factor Inventory neuroticism subscale (NEO-FFI-12). Statistical analyses included Pearson correlations, chi-square tests, and multivariate regression with interaction terms. Results: Among 364 participants (mean age 21.3 ± 2.3 years, 52.2% female), 47.0% reported severe insomnia symptoms (ISI 22–28), with 89.0% experiencing at least subthreshold symptoms (ISI ≥ 8) during the 2-week assessment period. These prevalence rates reflect symptom severity over a 2-week period during examination months and do not represent clinical diagnoses of chronic insomnia disorder, which requires ≥3 months of symptoms with clinical confirmation. High neuroticism (NEO-FFI ≥ 37) characterized 59.8% of students. Multivariate regression revealed a robust cross-sectional association between neuroticism and insomnia symptom severity (β = 0.239, 95% CI [0.173, 0.305], standardized β = 0.342, p < 0.001) and may reflect measurement during peak examination stress rather than stable trait-outcome relationships. Hostel residents showed non-significantly higher clinical insomnia prevalence than day scholars (75.9% vs. 67.5%, p = 0.081). Clinical-year students demonstrated significantly lower insomnia severity than pre-clinical students (β = −1.271, p < 0.001), a finding that contradicts assumptions about increasing stress through training progression. The neuroticism × living arrangement interaction was non-significant (p = 0.118); however, post hoc power analysis indicated the study was underpowered to detect small moderation effects, making this finding inconclusive. Conclusions: This study documents high insomnia symptom severity during a 2-week assessment period in Pakistani medical students, with a robust cross-sectional association with neuroticism. However, these findings must be interpreted within the constraints of the cross-sectional design, which cannot establish temporal precedence or causality between neuroticism and insomnia symptoms. These symptom prevalence rates likely reflect a combination of chronic sleep disorders and transient examination-related stress. Living arrangements showed small, non-significant associations with insomnia. The observed association between neuroticism and insomnia may be partially mediated or confounded by unmeasured variables, including academic stress, psychiatric comorbidities, substance use, and other sleep disorders. Findings suggest potential benefits from interventions addressing cognitive-emotional factors, though comprehensive diagnostic assessment is needed to distinguish chronic insomnia disorder from transient, stress-related sleep difficulties. Longitudinal research with objective sleep measures, structured psychiatric assessment, and systematic confounder evaluation is essential to establish causal relationships and intervention efficacy in this population. Full article

BioFlx crowns represent an innovative hybrid resin polymer-based alternative for pediatric full-coverage restorations, addressing the clinical dilemma between durable-but-unaesthetic stainless steel crowns (SSCs) and technique-sensitive zirconia crowns. This narrative review synthesizes current evidence of BioFlx crowns’ mechanical properties, clinical performance, and material characteristics through a comprehensive literature search across PubMed, Scopus, and Web of Science from August through September 2025. The search identified 18 studies comprising four randomized controlled trials, two case reports/series, and twelve in vitro studies. In vitro analyses demonstrated favorable stress distribution under physiological loads (≤311 N) with notable brand-dependent performance variations. NuSmile BioFlx exhibited greater wear than zirconia, but superior wear resistance compared to SSCs, while Kids-e-Dental BioFlx crowns demonstrated less crown wear relative to zirconia, with both brands causing less antagonist wear than zirconia. BioFlx showed intermediate fracture resistance, comparable surface roughness to SSCs but higher than zirconia, and intermediate marginal gaps. Resin cements demonstrated superior retention compared to manufacturer-recommended glass ionomer and resin-modified glass ionomer cements. Clinical studies with a 12 month follow-up demonstrated 92–98% retention rates compared to 100% for SSCs, with significantly higher patient satisfaction and reduced plaque accumulation versus SSCs. However, a failure rate of 6.7% was observed. Color change values were lower than those of zirconia crowns; however, they remained clinically unacceptable (ΔE > 3.3), and stain resistance was lower than that of SSCs. Marginal integrity remained clinically acceptable, though some anatomic form deterioration occurred over time. Case reports highlighted clinical utility in nickel-allergic patients and for masking silver diamine fluoride discoloration. BioFlx crowns represent a clinically valuable esthetic alternative in pediatric dentistry, though evidence remains limited by recent market introduction, brand-specific performance variations (NuSmile vs. Kids-e-Dental), anterior tooth applicability constraints, and contraindications in bruxism and for the Hall technique. Future randomized controlled trials with ≥2 year follow-up periods are imperative to establish long-term performance. Until such evidence emerges, BioFlx crowns represent a viable clinical option for esthetically sensitive cases and nickel-allergic patients when applied with rigorous case selection. Full article

This study aims to evaluate the biomechanical behavior of titanium and carbon fiber-reinforced polyetheretherketone (CF-PEEK) dental implants under varying bone densities and loading conditions using finite element analysis (FEA). A single-tooth mandibular molar implant system was modeled, comprising titanium or CF-PEEK abutment and fixture, and surrounding bone structures with four configurations: (I) fully cortical bone, (II) 2 mm cortical layer with trabecular bone, (III) 1 mm cortical with high-density trabecular bone, and (IV) 1 mm cortical with low-density trabecular bone. Vertical and oblique static loads of 100 N were applied to simulate masticatory forces. FEA results revealed that titanium implants exhibited higher von Mises stress values in the implant and abutment under oblique loading, exceeding 400 MPa, while CF-PEEK components showed reduced stress but significantly higher strain levels. Cortical and trabecular bone surrounding CF-PEEK implants received more uniform stress distribution, potentially minimizing stress shielding effects. However, fatigue life analyses indicated that CF-PEEK abutment and screw components were more susceptible to mechanical failure under oblique loads, particularly in low-density bone models. In conclusion, CF-PEEK implants offer a more physiological load transfer to bone and reduced stress shielding compared to titanium. However, their structural reliability under complex loading, especially in low-quality bone conditions, requires careful consideration. These findings support the potential use of CF-PEEK in select clinical scenarios but highlight the need for further material and design optimization. Full article

Background and Objectives: Diabetes mellitus (DM) is associated with impaired wound healing and increased oxidative stress, posing a significant challenge in dental wound healing. Low-level laser therapy (LLLT) has emerged as a potential regenerative treatment to enhance tissue repair. This study aims to investigate the effects of LLLT on oral mucosal wound healing and oxidative stress markers in rats with DM. Materials and Methods: Male Wistar rats (n = 108) were divided into six equal groups (healthy and diabetic, with or without mucosal ulcers, with or without LLLT). DM was induced with alloxan, and standardized mucosal ulcers were created. Every other day for 10 days, LLLT (6 J/cm²) was applied, and tissue samples were collected after 3, 7, and 10 days. Wound healing was assessed by planimetry, while systemic biochemical analyses included total oxidative status (TOS), total antioxidant capacity (TAC), superoxide dismutase (SOD) activity, and oxidative stress index (OSI). Results: LLLT significantly accelerated oral ulcer closure and showed between-group differences in redox markers. In healthy rats, LLLT increased wound closure on day 7 (p = 0.018). In diabetic rats, LLLT improved closure on day 3 (p = 0.035) and on day 7 (p = 0.001). Across groups, oxidative markers differed significantly (e.g., TOS on day 10 overall, p = 0.011; OSI on day 10 overall, p = 0.047; SOD p < 0.001 at all time points). In diabetic rats, on day 10, median TOS was lower with LLLT (p = 0.004). Conclusions: LLLT enhances oral wound healing and restores redox balance in diabetic rats, which supports the potential usage of LLLT as an adjunctive therapy for managing oral lesions in diabetic patients. Full article

Background: Dental caries arise from a multifactorial interplay between microbial dysbiosis, host immune responses, and enamel degradation visible on radiographs. Deep learning excels in image-based caries detection; however, integrative analyses that combine radiographic, microbiome, and transcriptomic data remain rare because public cohorts are seldom aligned. Objective: To determine whether three independent deep-learning pipelines—radiographic segmentation, microbiome regression, and transcriptome regression—can be reproducible implemented on non-aligned datasets, and to demonstrate the feasibility of estimating microbiome heritability in a matched twin cohort. Methods: (i) A U-Net with ResNet-18 encoder was trained on 100 annotated panoramic radiographs to generate a continuous caries-severity score from a predicted lesion area. (ii) Feed-forward neural networks (FNNs) were trained on supragingival 16S rRNA profiles (81 samples, 750 taxa) and gingival transcriptomes (247 samples, 54,675 probes) using randomly permuted severity scores as synthetic targets to stress-test preprocessing, training, and SHAP-based interpretability. (iii) In 49 monozygotic and 50 dizygotic twin pairs (n = 198), Bray–Curtis dissimilarity quantified microbial heritability, and an FNN was trained to predict recorded TotalCaries counts. Results: The U-Net achieved IoU = 0.564 (95% CI 0.535–0.594), precision = 0.624 (95% CI 0.583–0.667), recall = 0.877 (95% CI 0.827–0.918), and correlated with manual severity scores (r = 0.62, p < 0.01). The synthetic-target FNNs converged consistently but—as intended—showed no predictive power (R² ≈ −0.15 microbiome; −0.18 transcriptome). Twin analysis revealed greater microbiome similarity in monozygotic versus dizygotic pairs (0.475 ± 0.107 vs. 0.557 ± 0.117; p = 0.0005) and a modest correlation between salivary features and caries burden (r = 0.25). Conclusions: Modular deep-learning pipelines remain computationally robust and interpretable on non-aligned datasets; radiographic severity provides a transferable quantitative anchor. Twin-cohort findings confirm heritable patterns in the oral microbiome and outline a pathway toward future clinical translation once patient-matched multi-omics are available. This framework establishes a scalable, reproducible foundation for integrative caries research. Full article

Streptococcus mutans (S. mutans) is a cariogenic bacterium in the oral cavity that plays a significant role in plaque formation and dental caries. In previous research by our group, we showed that the endocannabinoid anandamide (AEA) has anti-bacterial and anti-biofilm activities against S. mutans. Here, we aimed to investigate its effects on S. mutans through metabolomics analyses. S. mutans was cultivated in the absence or presence of AEA at a sub-minimum inhibitory concentration (MIC), and changes in metabolites and metabolic pathways were assessed through liquid chromatography–mass spectrometry (LC-MS). Treatment of S. mutans using AEA at 10 µg/mL significantly disturbed the glycolytic flux in the bacteria, which was indicated by a reduced glucose uptake into the cell, suppression of key glycolytic intermediates, reduced acid production into the media, imbalance of NAD⁺/NADH, and decreased adenosine triphosphate (ATP) production. The disruption of carbohydrate metabolism impacts critical cellular processes, including energy production, redox balance, and biosynthetic pathways, leading to metabolic stress and impaired cellular function. These results highlight the mode of action of AEA as an antimicrobial agent. Altogether, these findings suggest that AEA has potential as a novel antimicrobial agent in the development of therapeutics against S. mutans. Full article

Background/Objectives: The expansion of National Health Insurance (NHI) coverage for dental implants in South Korea has substantially increased implant placements among older adults. While implants offer functional and esthetic benefits, their lack of periodontal ligaments alters occlusal force distribution, potentially increasing biomechanical stress on adjacent or opposing teeth. This study aimed to investigate the association between the increased number of dental implants and the incidence of cracked teeth following the introduction of implant insurance. Methods: A retrospective analysis was conducted using the Clinical Data Warehouse of Seoul St. Mary’s Dental Hospital. Patients who underwent molar crown restorations between 2014 and 2022 were included. The incidence and clinical features of cracked teeth were compared before (2014–2015) and after (2016–2022) the introduction of implant insurance. Statistical analyses assessed differences in symptom presentation, pulp status, and treatment outcomes. Results: Among 5044 molars restored with crowns, 1692 were diagnosed with cracks. The incidence of cracked teeth significantly increased after NHI coverage for implants (25.5% vs. 32.6%, p < 0.001). Cases after insurance implementation showed fewer signs and symptoms at initial presentation (67.4% vs. 50.0%, p < 0.001), reduced irreversible pulpitis (37.2% vs. 25.8%, p < 0.001), and increased preservation of pulp vitality (46.9% vs. 57.8%, p < 0.001). These shifts may reflect changes in occlusal adjustment practices and earlier clinical intervention. Conclusions: The findings suggest a temporal link between increased implant placement and the rising incidence of cracked teeth. Implant-induced occlusal changes may contribute to this trend. Careful occlusal evaluation and follow-up are essential after implant placement, and further prospective studies are warranted to confirm causality and refine prevention strategies. Full article

Background: Burnout syndrome (BS) is an occupational condition resulting from chronic stress, characterized by three dimensions, emotional exhaustion (EE), depersonalization (DE), and diminished personal accomplishment (PA), particularly prevalent in caregiving professions such as healthcare. The aim of this study is to analyse the prevalence of BS among Spanish dental implantology specialists, along with the impact of demographic, educational, and professional aspects. Methods: This is a cross-sectional observational study based on the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines and was open to respondents from May to December 2024. An electronic survey based on the Maslach Burnout Inventory—Human Services Survey (MBI–HSS) was sent to members of the Spanish Society of Implants. The data were analysed using descriptive analysis. Results: A total of 305 participants (20.9%) (31.5% females and 68.5% males) completed the questionnaire. The prevalence of BS was 4.3%; however, 61.0% of the dentists showed signs of suffering from the syndrome. The mean values of EE were “average” (20.3 ± 13.8) and of DE and EE “low” (5.1 ± 5.9, and 32.5 ± 14.5, respectively). The factors significantly associated with suffering from BS were being female and having more than 20 years of experience in dental implant treatments. Conclusions: It is advisable to conduct instructive and awareness-raising initiatives among dental professionals to promote an awareness of their mental health, ultimately aiming at preserving their physical and emotional well-being while delivering optimal care to their patients. Full article