BMC Oral Health最新文献

{"title":"The impact of abutment manufacturing techniques on reverse torque after cyclic loading and implant-abutment interface fitting: an in vitro study.","authors":"Alaa Mostafa AboRas, Ahmed Ismail Taha, Nourhan Ahmed Ragheb","doi":"10.1186/s12903-026-09530-w","DOIUrl":"10.1186/s12903-026-09530-w","url":null,"abstract":"<p><strong>Background: </strong>Screw loosening and implant-abutment interface (IAI) are critical for the long-term success of implant-supported restorations. This study aimed to evaluate the effect of abutment manufacturing technique on reverse torque values and micro-gap measurements at the implant-abutment interface.</p><p><strong>Methods: </strong>Thirty dental implant-abutment-crown complexes (Implance, Verdent, Turkey) were randomly allocated into three groups (n = 10 each) based on the abutment manufacturing technique: Group I-prefabricated titanium abutments (manufacturer-supplied, Implance, Verdent, Turkey; titanium grade 5); Group II-CAD-CAM-milled titanium abutments; Group III-3D-printed titanium abutments (Selective Laser Melting, SLM). All abutments featured an internal hexagonal connection with platform switching. All crown abutments were tightened to 25 Ncm and subjected to cyclic loading (100 N, 1.6 Hz, 250,000 cycles). Removal torque was measured before and after loading. Micro-gaps at the implant-abutment and abutment-screw interfaces were evaluated using scanning electron microscopy (SEM). Statistical analysis was performed using One-Way ANOVA with Tukey's Post Hoc test for reverse torque and the Kruskal-Wallis test for gap measurements (α = 0.05).</p><p><strong>Results: </strong>After cyclic loading, the 3D-printed (SLM) abutments exhibited significantly higher reverse torque values (11.08 ± 0.11 Ncm) compared to CAD-CAM-milled abutments (6.40 ± 0.79 Ncm) (P < 0.001). Prefabricated abutments demonstrated the highest post-loading torque values (13.31 ± 0.31 Ncm). All intragroup comparisons showed statistically significant reductions from baseline (P < 0.0001). No significant difference was found in implant-abutment interface gaps among groups (P = 0.105).</p><p><strong>Conclusion: </strong>Within the limitations of this study, prefabricated abutments demonstrated the highest reverse torque values after cyclic loading. 3D-printed abutments showed significantly greater resistance to torque loss compared to CAD-CAM-milled abutments, approaching the performance of prefabricated abutments. The implant-abutment fit was comparable across groups, suggesting that connection design may be more influential than manufacturing method for macroscopic fit. 3D-printed titanium abutments demonstrated significantly greater mechanical stability than CAD-CAM-milled abutments, approaching the performance of the gold-standard prefabricated abutments. This suggests that additive manufacturing may offer a clinically viable alternative to milling when both customization and mechanical integrity are required. However, clinical studies are needed to confirm these in vitro findings.</p>","PeriodicalId":9072,"journal":{"name":"BMC Oral Health","volume":"26 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2026-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13491918/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148788050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oral health status and associated influencing factors in children with attention-deficit/hyperactivity disorder: a case-control study.","authors":"Rui Dong, Han Wu, Feifei Jin, Qiqi Yang, Tongzhuo Chu, Hui Song","doi":"10.1186/s12903-026-09605-8","DOIUrl":"10.1186/s12903-026-09605-8","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Attention-deficit/hyperactivity disorder (ADHD) is the second most prevalent chronic pediatric condition worldwide. Its core ADHD symptoms-inattention, hyperactivity, and impulsivity-impair oral hygiene behaviors, and first-line medications such as methylphenidate may further increase oral disease risk. However, systematic epidemiological data on oral health status of children with ADHD remain limited in China. This study aimed to investigate oral health status of children with ADHD and identify factors associated with adverse oral health outcomes in this population.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;This case-control study included 130 children with ADHD and 143 age-matched healthy controls (6-12 years old) recruited from Dezhou Maternal and Child Health Hospital, Shandong Province, China, between July and December 2025. Oral examinations assessed dental caries (using the DMFT index for permanent teeth and dmft index for primary teeth, collectively reflecting the mixed-dentition caries burden), caries activity (Cariostat), periodontal status (Plaque Index [PI], Modified Gingival Index [MGI]), malocclusion, and dental trauma. Parent-reported questionnaires collected data on oral health behaviors, socioeconomic characteristics, and medication use. Between-group differences were analyzed using the Mann-Whitney U test, chi-square test, and Fisher exact test. Multivariate logistic regression with backward likelihood ratio selection was used to examine factors associated with adverse oral outcomes after adjusting for confounders. The English versions of the questionnaires are provided in Supplementary Files 1 and 2.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;The ADHD group had significantly higher overall dental caries prevalence (80.77% vs. 52.45%, P &lt; 0.001), higher median DMFT+dmft scores (3 vs. 1, P &lt; 0.001), higher plaque index (PI) scores (2 vs. 1, P &lt; 0.001), higher modified gingival index (MGI) scores (2 vs. 1, P &lt; 0.001), and higher Cariostat values (P &lt; 0.0001) than the control group. In contrast, the fissure sealant rate was significantly lower in the ADHD group (6.15% vs. 47.29%, P &lt; 0.001). Multivariate analysis showed that methylphenidate use (adjusted odds ratios [aOR] = 39.65, 95% CI: 15.79-271, P &lt; 0.001) and frequent candy consumption (aOR = 84.54, 95% CI: 12.2-584, P &lt; 0.001) were associated with higher odds of dental caries in the adjusted model. In contrast, a higher parental education level (college degree or above) was associated with lower odds of dental caries (aOR = 0.10, 95% CI: 0.014-0.684, P = 0.019). Perfunctory toothbrushing (aOR = 8.78, 95% CI: 3.12-24.71, P &lt; 0.001) was associated with higher odds of poor oral hygiene (PI ≥ 2), whereas higher household income (aOR = 0.29, 95% CI: 0.12-0.74, P = 0.009) and twice-daily toothbrushing (aOR = 0.14, 95% CI: 0.05-0.43, P = 0.001) were associated with lower odds of poor oral hygiene (PI ≥ 2). For gingivitis (MGI ≥ 2), higher household income (aOR = 0.33, 95%","PeriodicalId":9072,"journal":{"name":"BMC Oral Health","volume":"26 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2026-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13526303/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148857074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Root morphology and alveolar bone phenotype of maxillary second molars in patients with periodontitis: a cross-sectional study.","authors":"Xinyue Liu, Yifan Xie, Chuyi Jin, Mengyao Ding, Jiatong Zhang, Mengqing Yan, Lipei Liu, Ke Deng, Cheng Ding, Xing Chen","doi":"10.1186/s12903-026-09365-5","DOIUrl":"10.1186/s12903-026-09365-5","url":null,"abstract":"<p><strong>Background: </strong>Tooth anatomy is a key factor in periodontitis, and existing evidence has largely focused on premolars. The maxillary second molar (MSM), which is frequently affected and therapeutically challenging, remains substantially underexplored. This study aims to evaluate the root morphology and alveolar bone phenotype of the MSM in relation to periodontal parameters, aiming to identify high-risk anatomical sites and inform personalized management.</p><p><strong>Methods: </strong>This cross-sectional study included patients diagnosed with periodontitis at the Affiliated Hospital of Hangzhou Normal University between January 2022 and January 2025. Periodontal clinical parameters, including probing depth (PPD), clinical attachment loss (CAL), root furcation involvement (FI), and others, were recorded for all patients. Cone-beam computed tomography was used to assess alveolar bone loss (ABL), root concavity (angle and depth), root trunk length, root proximity, and adjacent third molars (M3s). Data were analyzed using SPSS, with p < 0.05 considered statistically significant.</p><p><strong>Results: </strong>The study included 319 patients (173 females and 146 males) with 576 MSMs aged 18 to 80 years (mean 43.5 ± 12.34 years). Triple-rooted (TR) morphology was most prevalent (55.21%, 318/576), followed by double-rooted (DR, 24.65%), single-rooted (SR, 19.44%), and quadruple-rooted (QR, 0.69%) morphologies. Both the angle and depth of root concavity were positively correlated with CAL and ABL. In the DR- and TR-types, inter-root proximity may serve as a potential risk indicator for FI. Thicker alveolar bone correlated with lower odds of stage III/IV and grade B/C periodontitis. The presence of adjacent M3s was associated with increased distal PPD, CAL, and ABL in MSMs.</p><p><strong>Conclusions: </strong>Our findings indicate that the specific root morphology and alveolar bone phenotype of MSMs are significantly associated with periodontitis. Anatomical features such as root concavity, inter-root proximity, and adjacent maxillary third molars may serve as potential risk indicators for localized periodontal destruction.</p>","PeriodicalId":9072,"journal":{"name":"BMC Oral Health","volume":"26 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2026-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13613663/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149036364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Classification model of preterm prelabor rupture of membranes risk using an artificial neural network model based on hematological, dental, and periodontal markers.","authors":"Mehmet Özsan, İsa Temur, Katibe Tuğçe Temur, Andaç Batur Çolak","doi":"10.1186/s12903-026-09623-6","DOIUrl":"10.1186/s12903-026-09623-6","url":null,"abstract":"<p><strong>Background: </strong>Preterm prelabor rupture of membranes (PPROM) is a multifactorial obstetric complication that contributes significantly to neonatal morbidity and mortality. Recent evidence suggests that systemic inflammation and periodontal health are critical determinants in the etiology of PPROM. However, conventional predictive methods often fail to integrate multidomain data for early risk assessment. This study aimed to develop an ANN-based model to classify PPROM status by integrating hematological inflammatory markers, periodontal indices, and maternal behavioral factors.</p><p><strong>Methods: </strong>A multilayer perceptron (MLP)-based artificial neural network (ANN) model was developed using data from 149 women (70 PPROM, 79 controls) and 24 input variables. Hematological parameters were derived from routine clinical blood tests obtained during late pregnancy or at hospital admission prior to delivery, while oral and periodontal indices were assessed within 24 h postpartum. Discriminative performance was evaluated using receiver operating characteristic (ROC) analysis (AUC, sensitivity, specificity), and mean squared error (MSE) was used as the training loss function.</p><p><strong>Results: </strong>The ANN model demonstrated high predictive performance with an MSE of 0.049, an R² value of 0.82, and an average deviation rate of -0.003%. These results indicate strong internal accuracy and suggest potential for generalizability. The model successfully captured complex, nonlinear relationships among biological and behavioral variables influencing PPROM risk.</p><p><strong>Conclusions: </strong>This study presents an interdisciplinary ANN framework integrating hematological, periodontal, and behavioral variables for delivery-period PPROM classification. The findings established in this study are characterized as associative given the postpartum collection of periodontal data, necessitating future prospective validation for clinical translation.</p>","PeriodicalId":9072,"journal":{"name":"BMC Oral Health","volume":"26 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2026-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13531878/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148863599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Association of articular eminence inclination and glenoid fossa roof thickness with sagittal skeletal classes: a CBCT study.","authors":"Mustafa Kenan Hürmüzlü, Sinem Coşkun Albayrak","doi":"10.1186/s12903-026-09609-4","DOIUrl":"10.1186/s12903-026-09609-4","url":null,"abstract":"<p><strong>Background: </strong>This study aimed to evaluate the association between skeletal sagittal relationship (based on ANB angle) and temporomandibular joint (TMJ) morphology by assessing bilateral articular eminence inclination (AEI) and glenoid fossa roof thickness, and to determine right-left symmetry patterns in these parameters.</p><p><strong>Methods: </strong>CBCT images of 123 individuals were analyzed. Skeletal classification was performed using ANB angle and participants were distributed equally into Skeletal Class I, II, and III (n = 41 each). AEI was measured bilaterally on sagittal TMJ sections relative to the Frankfort horizontal plane, and glenoid fossa roof thickness was recorded bilaterally. Side-to-side differences were evaluated using paired tests. Intergroup comparisons were performed across skeletal classes, and right-left associations were assessed using correlation analyses.</p><p><strong>Results: </strong>The cohort had a mean age of 40.1 ± 18.0 years (range: 11-84), with no significant differences across skeletal classes for age (p = 0.535) or sex distribution (p = 0.156). Right and left AEI showed a strong positive correlation (r = 0.764, p < 0.001), while glenoid fossa roof thickness demonstrated a moderate correlation between sides (ρ = 0.440, p < 0.001). The right AEI (48.0 ± 12.4°) was significantly higher than the left (46.4 ± 12.7°) (p = 0.033). No significant differences in AEI or glenoid fossa roof thickness were detected among skeletal classes, although left AEI tended to be lower in Class III (p = 0.082).</p><p><strong>Conclusions: </strong>TMJ measurements demonstrated high bilateral association with a small but significant right-left difference in AEI. Skeletal sagittal relationship, as determined by the ANB angle, was not significantly associated with AEI or glenoid fossa roof thickness in this sample.</p>","PeriodicalId":9072,"journal":{"name":"BMC Oral Health","volume":"26 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2026-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13576170/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148975585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regular dental scaling and dementia risk: a nationwide nested case-control study.","authors":"Ying-Ting Yeh, Nai-Chen Shih, Bo-Yuan Wang, Shun-Fa Yang, Yu-Hsun Wang, Chao-Bin Yeh, Ying-Cheng Chen","doi":"10.1186/s12903-026-09634-3","DOIUrl":"10.1186/s12903-026-09634-3","url":null,"abstract":"<p><strong>Background: </strong>Dementia is a major public health issue. Emerging evidence suggests that periodontal disease and dental calculus are associated with increased risk of dementia or may serve as potential risk indicators. The role of dental scaling in prevention remains unclear. This study aimed to investigate whether regular dental scaling is associated with dementia risk across age groups.</p><p><strong>Methods: </strong>We conducted a nested case-control study using data from the Taiwan National Health Insurance Research Database between 2000 and 2019. Cases were individuals with a first-time diagnosis of dementia during the study period, and controls were age-, sex-, and residence-matched individuals without dementia. Conditional logistic regression models were used to evaluate the association between dental scaling and the risk of dementia. A two-sided p-value < 0.05 was considered statistically significant.</p><p><strong>Results: </strong>The study included 162,038 participants. After adjusting for potential confounders, dental scaling was associated with modestly lower odds of dementia (OR 0.95, 95% CI 0.92-0.98; p = 0.004). Subgroup analyses suggested that the association was more evident among individuals aged 50-64 years, females, and residents of the central and eastern regions.</p><p><strong>Conclusions: </strong>Regular dental scaling may be associated with a modest reduction in the risk of dementia, particularly in individuals aged 50-64 years and in females. Although the association was statistically significant, the observed effect size was modest and should be interpreted cautiously. Further prospective studies are needed to confirm these findings and investigate the underlying mechanisms.</p>","PeriodicalId":9072,"journal":{"name":"BMC Oral Health","volume":"26 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2026-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13595680/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149023815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Therapeutic potential of dental follicle-derived stem cells and gold nanoparticles on osteoarthritic temporomandibular joint in guinea pigs (randomized prospective study).","authors":"Amira Mohsen Elsherbini, Samah Khaled Ezzat","doi":"10.1186/s12903-026-09529-3","DOIUrl":"10.1186/s12903-026-09529-3","url":null,"abstract":"<p><strong>Background: </strong>Osteoarthritis (OA) is a complicated autoimmune disease that often causes invasive inflammatory infiltration and serious articular destruction. The global prevalence of temporomandibular disorders (TMDs) is estimated to be around 30% of the population. Several clinical drugs have been reported to have adverse effects ranging from increased inflammation to liver cirrhosis. Even with the introduction of gene therapy, there is still a growing need for therapeutic alternatives for OA. This study aimed to evaluate the effect of dental follicle-derived stem cells (DFSCs) versus gold nanoparticles (AuNPs), on temporomandibular joint (TMJ) osteoarthritis induced by Complete Freund's Adjuvant (CFA).</p><p><strong>Methods: </strong>In this study, for osteoarthritis induction, twice intra-articular injections of complete Freund's adjuvant (CFA) were performed, once at the beginning of the experiment and again after two weeks. After 4 weeks, the osteoarthritis animals were randomly allocated into three equal groups: osteoarthritis group, osteoarthritis group treated with Nanogold (AuNPs), and osteoarthritis group treated with Dental follicle stem cells (DFSCs). After one month, the TMJs were fixed and processed for staining with hematoxylin and eosin, and the disc thickness was assessed; results were statistically evaluated.</p><p><strong>Results: </strong>The osteoarthritis group showed erosion of cartilage and subchondral bone and a thickened disc. Both DFSCs and AuNPs reduced the inflammatory signs. Though statistically non-significant, DFSCs showed a greater reduction in disc thickness.</p><p><strong>Conclusion: </strong>This study's results highlighted the potential use of DFSCs and AuNPs as a promising treatment in TMJ osteoarthritis.</p>","PeriodicalId":9072,"journal":{"name":"BMC Oral Health","volume":"26 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2026-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13491649/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148787756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation of artificial intelligence-assisted CBCT analysis for predicting inferior alveolar nerve proximity to impacted mandibular third molars: a diagnostic accuracy study.","authors":"Huan Hu, Jiahang Wu, Hongji Pu, Jichao Liang, Yan Niu, Jianghui Li, Bo Chen, Yixin Ding","doi":"10.1186/s12903-026-08690-z","DOIUrl":"10.1186/s12903-026-08690-z","url":null,"abstract":"<p><strong>Objectives: </strong>This study aimed to evaluate the diagnostic accuracy of an artificial intelligence (AI)-assisted cone-beam computed tomography (CBCT) analysis system for predicting the spatial proximity of the inferior alveolar nerve (IAN) to impacted mandibular third molars (M3M), using expert radiologist assessment as the reference standard.</p><p><strong>Methods: </strong>A retrospective diagnostic accuracy study was conducted on an internal institutional cohort of 312 patients (mean age 28.21 ± 6.62 years; January 2021-December 2024). A deep learning system employing a modified U-Net architecture automatically segmented the IAN canal and M3M on CBCT and classified the IAN-M3M spatial relationship into three categories: no contact (> 2 mm), proximity (0-2 mm), and contact/overlap. Diagnostic accuracy was evaluated on an independent hold-out test set of 486 M3 sites (283 patients). Two senior oral and maxillofacial radiologists provided the reference standard. Sensitivity, specificity, PPV, NPV, AUC, and Cohen's kappa were calculated; 95% CIs were derived by Wilson score method (proportions) and bootstrap resampling (AUC, kappa).</p><p><strong>Results: </strong>The AI system achieved an overall accuracy of 90.1% (438/486; 95% CI: 87.1-92.5%), weighted AUC of 0.925 (95% CI: 0.904-0.944), and Cohen's κ of 0.851 (95% CI: 0.821-0.912), indicating almost perfect agreement with the expert reference standard. Per-category sensitivity ranged from 88.2% to 91.2% and specificity from 92.8% to 97.4%. Bland-Altman analysis revealed a mean difference of 0.06 mm (95% LoA: -0.63 to 0.75 mm). Mean DSC was 0.90 ± 0.04 for IAN canal and 0.93 ± 0.03 for M3M segmentation. AI processing time was 4.75 ± 1.12 s versus 189.12 ± 41.99 s for expert assessment (39.79-fold reduction; P < 0.001). Subgroup analysis showed highest accuracy for mesioangular (93.1%) and horizontal (91.6%) impaction.</p><p><strong>Conclusions: </strong>The AI-assisted CBCT analysis system demonstrated high diagnostic accuracy and excellent agreement with expert radiological assessment in predicting IAN proximity to impacted mandibular third molars, while substantially reducing processing time. These results support the potential of AI-driven automated CBCT analysis as a preoperative decision-support tool; however, the reference standard was radiographic rather than intraoperative, and prospective multicenter validation incorporating surgical outcome data will be required before definitive clinical deployment recommendations can be made.</p>","PeriodicalId":9072,"journal":{"name":"BMC Oral Health","volume":"26 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2026-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13477586/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148763021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"\"Influence of macroretention in polymer-infiltrated ceramic network- and zirconia crowns and different roughness values of titanium bases on adhesive bond strength of hybrid abutment crowns: an in vitro study\".","authors":"Leonie Grander, Annika Kraus, Felicitas Hölken, Timpe Heidebrecht, Lisa Steiner, Samir Abou-Ayash, Stefan Wentaschek","doi":"10.1186/s12903-026-09606-7","DOIUrl":"10.1186/s12903-026-09606-7","url":null,"abstract":"<p><strong>Background: </strong>Two-piece hybrid abutment crowns (HACs) are CAD/CAM-fabricated implant restorations adhesively bonded to prefabricated titanium bases (Ti-bases). Since adhesive bond represents a potential weakness, methods to enhance long-term durability are being investigated. The aim of this in vitro study was to evaluate the influence of additional macroretention, specifically a circumferential groove, incorporated into polymer-infiltrated ceramic network (PICN) and zirconia crowns, and two Ti-base sandblasting protocols on adhesive bond strength of HACs.</p><p><strong>Methods: </strong>Ninety Ti-bases, 45 zirconia and 45 PICN crowns were divided into six groups (N = 15). Prior to conventional cementation (Panavia V5, Kuraray) of zirconia control group (Z1), Ti-bases and internal crown surfaces were sandblasted (Al₂O₃; 50 μm; 1.0 bar) and treated with MDP primer. In PICN control group (H1), Ti-bases were sandblasted identically and pretreated with Adiva M-Prime. Internal surfaces of PICN crowns were etched (5% hydrofluoric acid) and primed with Adiva C-Prime. In Z2 and H2, a circular groove in the internal crown surface was prepared as a macroretention in addition to conventional pretreatment as performed in Z1 and H1. Z3 and H3 were also conditioned conventionally, as in Z1 and H1, but Ti-bases were sandblasted with 250 μm at 2.0 bar. After sandblasting, surface roughness values (RV) of Ti-bases were measured. Following thermocycling, tensile shear test was performed, and failure mode was analysed. Mean values were compared using t-test.</p><p><strong>Results: </strong>RV differed significantly between differently blasted Ti-bases (p < 0.001). Both crown materials achieved significantly higher mean pull-off forces (Z1: 1085 N ± 79; H1 = 664 N ± 68) in control groups than in groups with macroretention (Z2: 1017 N ± 65; H2 = 438 N ± 48) (Z: p = 0.024, H: p < 0.001), and significantly lower pull-off forces than in groups with rougher Ti-bases (Z3: 1298 N ± 98, H3: 744 N ± 64) (Z: p < 0.001, H: p = 0.0023).</p><p><strong>Conclusions: </strong>Increasing pressure and grit size during corundum blasting of Ti-bases can achieve higher pull-off force for zirconia and PICN crowns. Additional macroretention, at least in the form used here, offers no advantage regarding bond strength.</p>","PeriodicalId":9072,"journal":{"name":"BMC Oral Health","volume":"26 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2026-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13476937/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148763202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of application delays on the dentin bond strength and interfacial morphology of different adhesive systems: an SEM analysis.","authors":"Ahmet Gültekin, Nilay Bayraktar, Osman Tolga Harorlı","doi":"10.1186/s12903-026-09596-6","DOIUrl":"10.1186/s12903-026-09596-6","url":null,"abstract":"<p><strong>Objective: </strong>This study evaluated the effect of application delays on the dentin bond strength of different adhesive systems used in composite restorations.</p><p><strong>Methods: </strong>Forty-five extracted human molars were randomly assigned to Clearfil SE Bond, G-Premio Bond, and Single Bond Universal (n = 15). Each adhesive was subdivided according to application time: immediate use, 3-minute delay, and 5-minute delay (n = 5). Adhesives were applied to occlusal dentin surfaces according to manufacturers' instructions, followed by composite build-up procedures. Microtensile bond strength (µTBS) was evaluated using a universal testing machine, and failure modes were examined microscopically. Selected specimens were analyzed using scanning electron microscopy (SEM).</p><p><strong>Results: </strong>Adhesive system (F = 48.32, p < 0.001) and application time (F = 22.72, p < 0.001) significantly influenced µTBS. The highest bond strength was observed in the immediate Clearfil SE Bond group (34.5 ± 4.8 MPa), whereas the lowest value was recorded in the 5-minute delayed G-Premio Bond group (13.4 ± 2.8 MPa). A 5-minute delay significantly reduced bond strength in all adhesive systems, whereas a 3-minute delay generally did not affect bonding performance. More than 85% adhesive failures were observed in the 5-minute delay groups. SEM analysis revealed porosity and crater-like surface defects in delayed universal adhesive groups.</p><p><strong>Conclusions: </strong>A 5-minute application delay significantly compromised dentin bond strength and increased adhesive failures. Immediate adhesive application is recommended to preserve bonding effectiveness and optimize restoration longevity.</p>","PeriodicalId":9072,"journal":{"name":"BMC Oral Health","volume":"26 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2026-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13520453/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148824925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}