European Journal of Dentistry最新文献

{"title":"Evaluation of a Novel Calcium-Binding Peptide for Enamel Remineralization: An In Vitro SEM-EDX Study.","authors":"Ozge Erken Gungor, Buse Nur Gok, Kadriye Altunbas, Oguz Ozturk","doi":"10.1055/s-0046-1820116","DOIUrl":"https://doi.org/10.1055/s-0046-1820116","url":null,"abstract":"<p><strong>Objectives: </strong>The increasing demand for biocompatible and effective alternatives to fluoride in enamel remineralization has prompted the development of novel synthetic peptides with a high affinity for calcium. This in vitro study aimed to assess the remineralization potential of one such peptide on artificially induced carious lesions in both primary and permanent enamel, in comparison with fluoride and untreated controls.</p><p><strong>Materials and methods: </strong>An in vitro study was conducted in two phases: pilot and comprehensive. Three peptides (P1-P3) were newly synthesized based on amino acid sequences with high calcium affinity (patent pending). In the pilot phase (<i>n</i> = 44), enamel samples were treated with peptides (200/400 µg/mL), fluoride, or left untreated. Based on preliminary results, P2 and P3 (800 µg/mL) were selected for the comprehensive phase (<i>n</i> = 144). Scanning electron microscopy with energy dispersive X-ray (SEM-EDX) analysis was performed at initial, after demineralization, and after pH cycling.</p><p><strong>Statistical analysis: </strong>Statistical analyses were performed using SPSS software (version 18.0; SPSS Inc., Chicago, Illinois, United States). Descriptive statistics were calculated for calcium and phosphorus levels. Intragroup comparisons were conducted using paired Student's <i>t</i>-test or Wilcoxon's signed-rank test, while intergroup comparisons were performed using one-way analysis of variance (ANOVA) or Kruskal-Wallis test, followed by Tukey HSD or Mann-Whitney <i>U</i>-test where appropriate. The significance level was set at <i>p</i> < 0.05.</p><p><strong>Results: </strong>P2 treatment significantly increased Ca²⁺ levels in both primary and permanent enamel compared with controls (<i>p</i> < 0.05). The increase was higher than in the fluoride group, though not statistically significant. No meaningful change in phosphorus levels was observed across groups (<i>p</i> > 0.05).</p><p><strong>Conclusion: </strong>This study suggests that novel peptide-based agents may offer effective remineralization in early enamel lesions, particularly in primary teeth. They may serve as promising alternatives to fluoride in pediatric dentistry.</p>","PeriodicalId":12028,"journal":{"name":"European Journal of Dentistry","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147835502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Marginal Gap and Fracture Strength of Hybrid, Zirconia-Reinforced, and Virgilite-Reinforced CAD/CAM Ceramic Crowns.","authors":"Diaaeldin Farag, Hatem Mostafa El-Damanhoury, Heba Mohamed Abdelaal","doi":"10.1055/s-0046-1820080","DOIUrl":"https://doi.org/10.1055/s-0046-1820080","url":null,"abstract":"<p><strong>Objectives: </strong>This <i>in vitro</i> study evaluated the vertical marginal gap and fracture strength of four CAD/CAM (computer-aided design/computer-aided manufacturing) ceramic materials: a hybrid ceramic (Vita Enamic, Vita Zahnfabrik; VE), zirconia-reinforced lithium silicate (Vita Suprinity, Vita Zahnfabrik; VS), Virgilite-containing lithium disilicate (Cerec Tessera, Dentsply Sirona; CT), and using lithium disilicate (IPS e.max CAD, Ivoclar; Emax) as a control.</p><p><strong>Materials and methods: </strong>A standardized all-ceramic crown preparation was conducted on a first maxillary premolar tooth. The prepared tooth was duplicated into 40 epoxy resin dies, allocated into four groups (<i>n</i> = 10) according to the four ceramic materials tested. The crowns' marginal gaps were measured using a metallurgical microscope. Cementation of the crowns was done using a self-adhesive resin cement, then tested to failure under a single load using a universal testing machine. The results were statistically analyzed with one-way ANOVA (analysis of variance) and post-hoc Tukey's honest significant difference tests.</p><p><strong>Results: </strong>VS crowns demonstrated significantly higher (<i>p</i> < 0.001) marginal gap (80.14 ± 7.64 µm) than the other materials, VE (55.56 ± 7.20 µm), CT (58.20 ± 5.22 µm), and Emax (60.13 ± 3.63 µm), whereas VE (1,002.8 ± 78.9 N) showed significantly lower (<i>p</i> < 0.001) fracture strength value than CT (1,850 ± 90 N), Emax (1761.6 ± 101 N), and VS (1633.5 ± 149.5 N).</p><p><strong>Conclusions: </strong>All tested materials exhibited clinically acceptable marginal gaps and fracture strength values that exceeded the maximum reported masticatory forces. CT exhibited the highest fracture strength, while VE showed the lowest marginal gap. CT's superior fracture strength and excellent marginal fit highlight its suitability for mechanically challenging posterior restorations while maintaining marginal integrity.</p>","PeriodicalId":12028,"journal":{"name":"European Journal of Dentistry","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147766478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Circular RNAs in Oral Squamous Cell Carcinoma: A Systematic Review of Emerging Diagnostic and Prognostic Biomarkers.","authors":"Omar Abdul Jabbar Abdul Qader, Asmaa Uthman, Walid Elsayed, Natheer Al-Rawi","doi":"10.1055/s-0046-1819725","DOIUrl":"https://doi.org/10.1055/s-0046-1819725","url":null,"abstract":"<p><strong>Abstract: </strong>Oral squamous cell carcinoma (OSCC) remains a major global health burden, with poor survival rates due to late diagnosis and limited prognostic precision. Circular RNAs (circRNAs) are a novel class of non-coding RNAs characterized by their covalently closed loop structure, conferring stability and tissue specificity. Recent evidence suggests circRNAs hold promise as diagnostic and prognostic biomarkers in OSCC. This article aims to systematically evaluate the diagnostic accuracy, prognostic value, and expression profiles of circRNAs in OSCC. We searched PubMed, Scopus, EBSCO, and Google Scholar databases (inception-August 2025) for studies assessing circRNAs in OSCC. Eligible studies reported diagnostic metrics (sensitivity, specificity, and AUC), prognostic outcomes (hazard ratios [HRs]), or differential expression data. Risk of bias was assessed using QUADAS-2 and NOS. Data were synthesized qualitatively. A total of 29 studies were included. Tissue-based circRNAs showed moderate diagnostic performance (AUC: 0.74-0.81), while saliva- and plasma-derived circRNAs demonstrated higher accuracy (AUC up to 0.922). Prognostic studies revealed oncogenic circRNAs were associated with poor overall survival (pooled OS HR ≈ 2.38), whereas tumor-suppressor circRNAs predicted favorable outcomes (pooled OS HR ≈ 0.43). Exosomal circRNAs, particularly circ-0000199, emerged as independent predictors of recurrence and mortality. CircRNAs exhibit strong potential as diagnostic and prognostic biomarkers in OSCC, particularly in liquid biopsy applications. However, heterogeneity, small sample sizes, and lack of multicenter validation limit immediate clinical translation. Larger, standardized studies are warranted to confirm their utility.</p>","PeriodicalId":12028,"journal":{"name":"European Journal of Dentistry","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147766505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physicomechanical and Antibacterial Properties of Resin-Based Dental Sealants Modified with Graphene Oxide Nanoparticles.","authors":"Ploypim Kraisintu, Suparaksa Yamockul, Tool Sriamporn, Niyom Thamrongananskul, Awiruth Klaisiri, Theerapat Chanamuangkon, Somphob Thompho, Thanchanok Suriyapongprapai, Guang Hong","doi":"10.1055/s-0046-1819726","DOIUrl":"https://doi.org/10.1055/s-0046-1819726","url":null,"abstract":"<p><strong>Objectives: </strong>This study evaluated the influence of incorporating graphene oxide (GO) nanoparticles (0.1, 0.25, and 0.5 wt%) into resin-based pit and fissure sealants on their mechanical, physical, antibacterial, and cytocompatible properties, compared with a commercial reference material.</p><p><strong>Materials and methods: </strong>Experimental sealants containing GO (G2-G4) were prepared, with an unmodified resin as control (G1) and Helioseal F Plus as commercial comparison (G5). GO morphology was characterized by TEM. Specimens (<i>n</i> = 240) were tested for Vickers microhardness, viscosity, surface roughness change (ΔRa) after simulated toothbrushing, and fluorescence (% blue channel). Antibacterial activity against <i>Streptococcus mutans</i> was assessed using a direct contact test (ASTM E2180), and antibacterial rate (AR) was calculated. Cytotoxicity was evaluated via MTT assay with human gingival fibroblasts following ISO 10993-5. Data were analyzed using one-way ANOVA and Tukey's post hoc test (<i>α</i> = 0.05).</p><p><strong>Results: </strong>GO incorporation significantly increased microhardness, with G4 (0.5 wt% GO) showing the highest VHN (<i>p</i> < 0.05). Viscosity rose modestly with GO content, while the commercial sealant exhibited the highest value. G3 (0.25 wt% GO) displayed the lowest ΔRa after brushing. All GO groups showed higher fluorescence than the control (<i>p</i> < 0.05). Antibacterial activity increased with GO concentration (AR = 83.84-88.88%), though G5 achieved the highest AR (99.42%). All formulations maintained > 70% cell viability, confirming acceptable biocompatibility.</p><p><strong>Conclusion: </strong>Low-level GO reinforcement enhanced surface hardness, wear resistance, fluorescence, and antibacterial performance of resin-based sealants without compromising cytocompatibility. GO represents a promising multifunctional nanofiller for next-generation sealants aimed at improving durability and caries prevention.</p>","PeriodicalId":12028,"journal":{"name":"European Journal of Dentistry","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147766497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Addressing Ethical Issues in Biomedical and Dental Publishing.","authors":"Luca Fiorillo","doi":"10.1055/s-0046-1820079","DOIUrl":"https://doi.org/10.1055/s-0046-1820079","url":null,"abstract":"","PeriodicalId":12028,"journal":{"name":"European Journal of Dentistry","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147766512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative In Vitro Evaluation of Early Cell Responses of Porous and Nonporous Polycaprolactone Electrospun Nanofibrous Membrane for Guided Tissue Regeneration.","authors":"Soumya Sheela, Fatma Mousa AlGhalban, Khalil Abdelrazek Khalil, Sausan Al Kawas, Ensanya A Abou Neel","doi":"10.1055/s-0046-1820078","DOIUrl":"https://doi.org/10.1055/s-0046-1820078","url":null,"abstract":"<p><strong>Objective: </strong>The production of porous polycaprolactone (PCL) electrospun fibers has already been reported in the literature. However, most of the studies reported the production of porous fibers on a micrometer scale. Hence, the main aim of this study is to (1) fabricate PCL membranes with secondary nanoporous fibers to improve the attachment, spreading, and proliferation of cells, and subsequent extracellular matrix deposition and (2) evaluate its biocompatibility on different cell types in comparison to a nonporous one.</p><p><strong>Materials and methods: </strong>Secondary nanopores were introduced by adjusting humidity and employing a binary solvent system of chloroform and dimethyl sulfoxide. The membranes were characterized using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) analysis, and water contact angle. The biological activity on cells was assessed using the XTT assay, cell adhesion and spreading were analyzed by FE-SEM and confocal studies, and gene expression was measured by real-time polymerase chain reaction. Human fetal osteoblasts (hFOBs), human gingival fibroblasts (HGFs), and human umbilical vein endothelial cells (HUVECs) were utilized for cell-biomaterial interaction studies.</p><p><strong>Statistical analysis: </strong>Two-way ANOVA (analysis of variance) followed by Tukey's multiple comparison was used to assess the statistical significance.</p><p><strong>Results: </strong>The FE-SEM analysis revealed an average fiber diameter of 774 ± 193 nm for the porous membrane and 642 ± 176 nm for the nonporous membrane, with secondary nanopores averaging 151 ± 31 nm in length. The XRD analyses confirmed characteristic fingerprint vibrational bands of PCL for both membrane types. Water contact angle measurement showed no significant differences, with porous membranes at 131 ± 2° and nonporous membranes at 122 ± 10°. Both the porous and nonporous membranes displayed comparable cell viability. The porous membranes showed a tendency toward good cell spreading with statistically significant upregulation of type I collagen (COL-I) in hFOBs, and vascular endothelial growth factor (VEGF) expression in HUVECs compared with the nonporous membranes.</p><p><strong>Conclusion: </strong>The cells on porous membranes demonstrated a trend toward improved spreading and functional activity compared with those on nonporous surfaces. However, considering the exploratory nature of this work, and the lack of mechanical and functional tests, it is too early to draw a definitive conclusion on the superiority of porous PCL membranes over nonporous ones.</p>","PeriodicalId":12028,"journal":{"name":"European Journal of Dentistry","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147766481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sustainable Dental Waste Management Practices in Bangladesh: Aligning with the UN SDG 2030 Agenda.","authors":"Sanjida Haque, Mohammad Nurunnabi, M Tasdik Hasan, Ehsanul Hoque Apu","doi":"10.1055/s-0046-1820076","DOIUrl":"https://doi.org/10.1055/s-0046-1820076","url":null,"abstract":"<p><strong>Objective: </strong>The management of dental waste is a key aspect of Sustainable Development Goals (SDGs): 3 (good health), 6 (clean water), and 12 (responsible consumption). In Bangladesh, a lack of resources and unequal implementation can be contributing factors to unsafe clinical waste practices. Therefore, the purpose of the present study was to explore the level of awareness, reported practices, and adherence to the World Health Organization (WHO) and DGHS biomedical waste-related guidance on the part of dental professionals.</p><p><strong>Materials and methods: </strong>A cross-sectional survey assembly was used to gather data from 1,000 working dental professionals (September to November 2023). Data were analyzed in SPSS v29. Demographics, awareness, and practices were collated using descriptive statistics. Participants were grouped as high, moderate, and low compliance by an artificially derived compliance score (0-8). Logistic regression was used to test relationships among variables based on semi-phase predictors and good practice.</p><p><strong>Results: </strong>No participants met the criteria for high compliance. Overall, 68.3% (<i>n</i> = 683) demonstrated moderate compliance and 31.7% (<i>n</i> = 317) demonstrated low compliance. Only 15% reported receiving formal waste management training, and 38.4% were aware of WHO color-coding guidelines. Incautious disposal was prevalent: 37.7% found themselves disposing of sharps into regular cans, and 24.0% disposed of amalgam in general waste. Logistic regression analysis did not identify statistically significant associations between measured individual-level predictors and compliance (Omnibus <i>χ</i> ² (7) = 3.141, <i>p</i> = 0.872; Hosmer-Lemeshow <i>χ</i> ² = 3.899, <i>p</i> = 0.866), with minimal explained variance, indicating limited explanatory value of the included predictors.</p><p><strong>Conclusion: </strong>The findings indicate partial and inconsistent compliance with recommended biomedical waste practices among dental professionals. While the study does not measure SDG indicators directly, the results highlight areas of policy relevance in relation to SDG targets 3.9, 6.3, and 12.4. Strengthening regulatory enforcement, structured training programs, and system-level infrastructure support may be important considerations for improving compliance.</p>","PeriodicalId":12028,"journal":{"name":"European Journal of Dentistry","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147766494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Analysis of Occlusal Parameters in Post-Orthodontic Patients with and without Non-Carious Cervical Lesions Using T-Scan III.","authors":"Mayurach Pipatphatsakorn, Nattapat Khamnuengsitthi, Jittima Pumklin, Ratchawan Tansalarak","doi":"10.1055/s-0046-1820077","DOIUrl":"https://doi.org/10.1055/s-0046-1820077","url":null,"abstract":"<p><strong>Objectives: </strong>This study aimed to determine the relationship between occlusal and clinical factors-including relative occlusal force, occlusion time (OT), disclusion time (DT), and occlusal schemes-and the occurrence of non-carious cervical lesions (NCCLs) in post-orthodontic patients, using the T-Scan III system.</p><p><strong>Materials and methods: </strong>Fifty-two patients who completed fixed orthodontic treatment within 1 year were purposively selected and divided into two groups: those with NCCLs (<i>n</i> = 26) and those without NCCLs (<i>n</i> = 26). A total of 1,336 teeth were evaluated (111 with NCCLs, 1,225 without). Data collection included a questionnaire, clinical examination, and T-Scan III recordings.</p><p><strong>Statistical analysis: </strong>Pearson's chi-square and multiple comparison tests were used for categorical variables. Relative occlusal forces were compared using the Mann-Whitney U-test, while OT and DT were analyzed with independent-sample <i>t</i>-tests. Multiple linear regression identified predictive factors for NCCLs at both the subject and tooth levels. The significance level was set at <i>p</i> < 0.05.</p><p><strong>Results: </strong>Older age, combined orthodontic-orthognathic surgery, and gingival recession were significantly associated with NCCL occurrence (<i>p</i> < 0.05). Group-function occlusion was the only significant occlusal predictor (<i>β</i> = 0.365, <i>p</i> = 0.018). At the tooth level, gingival recession significantly predicted NCCLs (<i>β</i> = 0.499, <i>p</i> < 0.001). The regression models explained 12.5 and 22.9% of the variance in NCCL occurrence at the subject and tooth levels, respectively. Teeth with NCCLs showed higher relative occlusal forces at maximum intercuspation (8.16 ± 8.41%) and during eccentric movements (37.86 ± 31.38%) than teeth without NCCLs (7.53 ± 9.26% and 30.09 ± 29.16%, respectively; <i>p</i> < 0.05). Mean OT (0.27 ± 0.07 seconds) and DT (0.50 ± 0.13 seconds) were significantly longer in NCCL subjects than in controls (OT: 0.22 ± 0.06 seconds; DT: 0.42 ± 0.11 second; <i>p</i> < 0.05).</p><p><strong>Conclusion: </strong>Prolonged occlusion and DTs, higher relative occlusal forces, and group-function occlusion were significantly associated with the presence of NCCLs in post-orthodontic patients. Quantitative occlusal analysis using the T-Scan III system may help clinicians detect functional imbalances and prevent NCCL development during orthodontic follow-up.</p>","PeriodicalId":12028,"journal":{"name":"European Journal of Dentistry","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147766461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing Osteoporosis Risk on Panoramic Radiography through Fractal Dimension Analysis of Mandibular Condyles in Postmenopausal Women.","authors":"Sri Wigati Mardi Mulyani, Yunita Savitri, Alhidayati Asymal, Deny Saputra, Putri Alfa Meirani Laksanti, Norliza Ibrahim","doi":"10.1055/s-0046-1820075","DOIUrl":"10.1055/s-0046-1820075","url":null,"abstract":"<p><strong>Objectives: </strong>The study aimed to analyze the trabecular bone structure pattern of the condylar bone on panoramic radiography using fractal dimension (FD) analysis and to identify the correlation between FD and bone mineral density (BMD) values to assess osteoporosis risk in postmenopausal women.</p><p><strong>Materials and methods: </strong>This study involved 150 panoramic radiographs of postmenopausal women aged ≥50 years who were diagnosed with normal, osteopenia, and osteoporosis based on BMD values. FD analysis was performed on the condylar bone to establish standard FD values for normal, osteopenia, and osteoporosis conditions. The analysis was performed on the condylar bone using the box-counting method in ImageJ software to obtain FD values from skeletonized binary images of 30 × 30 pixel regions of interest (ROIs) on both condylar heads.</p><p><strong>Statistical analysis: </strong>The normality of the data was assessed using the Shapiro-Wilk test, and correlations between variables were evaluated using Spearman's rank correlation analysis.</p><p><strong>Results: </strong>There was a significant positive correlation (<i>p</i> < 0.001) between FD and BMD values, with moderate correlation strength (<i>r</i> = 0.462 for ROI 1 and <i>r</i> = 0.518 for ROI 2). Higher BMD values were associated with higher FD values, and vice versa. Low FD values indicated low trabecular bone density (osteoporosis), while higher FD values reflected better trabecular bone density (normal).</p><p><strong>Conclusion: </strong>FD analysis of the mandibular condyles can serve as an indicator of osteoporosis. It complements BMD by quantifying trabecular bone structural changes, offering a method for early osteoporosis detection.</p>","PeriodicalId":12028,"journal":{"name":"European Journal of Dentistry","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147697799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection of Failure and Measurement of Number of Cycles to Failure of Nickel-Titanium Rotary files in Bending Fatigue Testing.","authors":"Teeramate Kessaro, Sarita Morakul, Sirawut Hiran-Us, Pairod Singhatanadgid","doi":"10.1055/s-0046-1817165","DOIUrl":"10.1055/s-0046-1817165","url":null,"abstract":"<p><strong>Objectives: </strong>This study aimed to (1) develop a novel method for fabricating simulated root canals, (2) introduce a reliable approach for detecting file fractures, and (3) establish a direct measurement technique for determining the number of cycles to failure (NCF) in bending fatigue tests of rotary files.</p><p><strong>Materials and methods: </strong>Bending fatigue tests were conducted using a custom setup consisting of a simulated root canal, a handpiece-controller unit, and a signal extraction module for monitoring motor current and encoder signals. The simulated canals were fabricated to match the geometry of 25.06 ZenFlex rotary files, and included five configurations with varying radii (2, 5, and 8 mm) and angle of curvature (30°, 45°, and 60°). Tests were performed at room and body temperatures. File fracture was identified by an abrupt drop in motor current, and the NCF was directly determined from encoder-derived revolution counts. To verify accuracy, encoder-based revolution counts were compared with those measured with a mechanical counter. In addition, the proposed method was benchmarked against the conventional time-based calculation of NCF.</p><p><strong>Results: </strong>The fabricated canals provided precise confinement of the files, ensuring reproducible curvature with negligible torsional distortion. Fractographic analysis revealed fatigue features, including striations radiating from the crack origin and dimples in the fast-fracture zone, confirming bending fatigue as the dominant failure mechanism. Encoder-based revolution counts closely matched those from the mechanical counter, with discrepancies of less than one revolution, and yielded slightly lower values than the conventional time-based method. Statistical analysis showed no significant difference between the proposed and conventional methods (<i>p</i> > 0.05). Fatigue life was significantly reduced at body temperature compared with room temperature (<i>p</i> < 0.05) and increased with larger radii of curvature (<i>p</i> < 0.05), while angle of curvature had no significant effect (<i>p</i> > 0.05).</p><p><strong>Conclusions: </strong>The proposed simulated root canals improved reproducibility and standardization of <i>in vitro</i> fatigue testing of files. The signal extraction method provided accurate revolution counts and a more realistic estimation of NCF than conventional time-to-failure methods, which overestimated actual values by 1.85 to 6.28% in this study.</p>","PeriodicalId":12028,"journal":{"name":"European Journal of Dentistry","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147697919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}