Dental Materials最新文献

{"title":"Long-term clinical performance of bilaminar veneers combined with the Dahl concept for the management of localized anterior tooth wear: An ambispective cohort study.","authors":"Edina Lempel, Kinga Dorottya Németh, Erika Katalin Dunavári, Sára Jeges, József Szalma","doi":"10.1016/j.dental.2026.04.018","DOIUrl":"https://doi.org/10.1016/j.dental.2026.04.018","url":null,"abstract":"<p><strong>Objectives: </strong>To evaluate the long-term clinical performance of bilaminar restorations-functional palatal resin-based composite (RBC) veneers (PVs) combined with labial ceramic veneers (LVs) - used for the rehabilitation of localized anterior tooth wear with the Dahl concept, with emphasis on survival, failure patterns, and material- and patient-related risk factors.</p><p><strong>Methods: </strong>Twenty-six patients (156 maxillary anterior teeth) received bilaminar restorations. PVs were fabricated from RBCs (Enamel Plus HRi BioFunction or Estelite Sigma Quick), and LVs from lithium disilicate ceramics (IPS e.max Press or GC Initial LiSi Press). Clinical evaluation was performed at 3-5 and 6-8 years using USPHS criteria. Outcomes were classified as success, survival with deficiencies, or failure requiring replacement. Survival was analyzed using Kaplan-Meier estimates, and risk factors were assessed by multivariable regression analysis (p < 0.05).</p><p><strong>Results: </strong>Cumulative survival was 92.3% for PVs and 98.1% for LVs. Fifteen restorations (4.8%) required replacement, predominantly PVs due to wear- and fatigue-related deterioration. No survival difference was observed between LVs. PV performance showed significant material-related differences, with Estelite Sigma Quick exhibiting fewer failures and higher success rates than Enamel Plus HRi BioFunction. Unsatisfactory oral hygiene, bruxism, coffee/tea consumption, and increasing restoration age were associated with higher failure risk. Baseline erosion severity significantly affected PVs, but not LVs outcomes.</p><p><strong>Significance: </strong>Bilaminar restorations combined with the Dahl concept offer a durable, minimally invasive solution for localized anterior tooth wear over up to eight years. However, while LVs demonstrate excellent long-term stability, the performance of functional PVs remains material-dependent and requires ongoing maintenance.</p>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":" ","pages":""},"PeriodicalIF":6.3,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147809230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of nanowire technology in dentistry: A narrative review.","authors":"Ya Zhang, Yipeng Fu, Kai Chun Li, Manikandan Ekambaram, Ruoxi Dai, Paul R Cooper, Quan-Li Li, May Lei Mei","doi":"10.1016/j.dental.2026.04.020","DOIUrl":"https://doi.org/10.1016/j.dental.2026.04.020","url":null,"abstract":"<p><p>Nanowire technology utilizes one-dimensional wire-like structures (nanowires) to create materials with a high aspect ratio and tunable surface chemistry. These nanowires can be synthesized from diverse material classes, including metallic, bioceramic, semiconductor, and polymer systems, each offering distinct structural and functional advantages. This technology has been used in dental research to synthesize different materials for a wide range of clinical applications. The core of the review details multifaceted applications of nanowires of different materials. They serve as potent, multifunctional fillers, such as silver nanowires, which can enhance the mechanical strength and impart sustained antibacterial activity to restorative materials. When applied as coatings on titanium implants, metallic nanowires, such as zinc- or magnesium-based nanowires, synergistically promote osseointegration and provide antibacterial defense through controlled ion release or photocatalytic self-cleaning. In regenerative dentistry, nanowire-based scaffolds, most notably hydroxyapatite nanowire scaffolds, guide periodontal bone and soft tissue healing by providing structural support combined with bioactive signaling and immunomodulation. Beyond structural use, silver and silicon nanowires enable highly sensitive diagnostic platforms for detecting oral cancer biomarkers and facilitating on-demand drug delivery. Notably, ultralong hydroxyapatite nanowires with exceptionally high aspect ratios (>10,000) are being engineered into hierarchical, biomimetic materials that replicate the exceptional mechanics and aesthetics of natural enamel. While promising, the transition to clinical practice requires addressing key challenges regarding long-term biosafety, standardized evaluation protocols, and scalable manufacturing.</p>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":" ","pages":""},"PeriodicalIF":6.3,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147809173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical, translucency, tribological resistance, and biocompatibility of lithium disilicate glass-ceramics produced by ZrO₂ doping and digital light processing for dental prosthesis.","authors":"Qianshu Xia, Xian Tong, Xin Zhou, Zengqi Ye, Xiaomin Xu, Yuchen Feng, Li Zhu, Zhaoping Chen, Yuncang Li, Jixing Lin, Cuie Wen, Jianfeng Ma","doi":"10.1016/j.dental.2026.04.014","DOIUrl":"https://doi.org/10.1016/j.dental.2026.04.014","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Lithium disilicate glass-ceramics (LDGCs) have become one of the most widely used dental prosthesis materials in clinical practice due to their excellent esthetics, biocompatibility, and enamel-like wear resistance. However, their inherent brittleness, limited mechanical strength, and progressive wear under long-term service have restricted their application in high-stress posterior regions. Herein, this study aims to develop zirconia (ZrO&lt;sub&gt;2&lt;/sub&gt;)-reinforced LDGCs and systematically investigate the effects of ZrO&lt;sub&gt;2&lt;/sub&gt; content on microstructure evolution and mechanical, translucency, tribological, and biological performance.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;ZrO&lt;sub&gt;2&lt;/sub&gt;-reinforced LDGCs (LDGCxZ, where x = 0, 2, 4, 6 mol%, designated as LDGC, LDGC2Z, LDGC4Z, and LDGC6Z) with varying ZrO&lt;sub&gt;2&lt;/sub&gt; contents were fabricated via a melting-derived powder processing route combined with digital light processing, debinding, and sintering. The LDGCxZ samples were systematically characterized for their microstructural evolution, mechanical properties, translucency, tribological behavior, and biological performance through biaxial flexural strength testing, aging resistance testing, Weibull two-parameter distribution analysis, Vickers hardness testing, fracture toughness analysis, nanoindentation testing, and tribological evaluation. Furthermore, hemocompatibility, cytocompatibility, and in vivo biological responses were assessed using hemolysis assays, CCK-8 assays, live/dead staining, phalloidin staining, subcutaneous implantation in a rat model, and comprehensive biosafety evaluation.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;4 mol% ZrO&lt;sub&gt;2&lt;/sub&gt; doping optimally refines the crystalline structure, creating a homogeneous dual-phase of Li&lt;sub&gt;2&lt;/sub&gt;Si&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;5&lt;/sub&gt; and Li&lt;sub&gt;2&lt;/sub&gt;SiO&lt;sub&gt;3&lt;/sub&gt; that effectively minimizes internal defects, while excessive doping (6 mol%) leads to abnormal grain growth and porosity formation. Impressively, the sintered LDGC4Z sample (4 mol% ZrO&lt;sub&gt;2&lt;/sub&gt;) exhibited exceptional comprehensive properties: a flexural strength of ∼294 MPa, fracture toughness of ∼4.1 MPa m&lt;sup&gt;1/2&lt;/sup&gt;, elastic modulus of ∼111.4 GPa, and Vickers hardness of ∼644 HV, and a 150% enhancement in the translucency parameter, alongside superior anti-aging resistance and tribological behavior closely matching that of natural enamel. The LDGC4Z sample also confirmed excellent hemocompatibility, favorable cytocompatibility with human gingival epithelial cells, and stable tissue integration in subcutaneous implantation models. Collectively, the LDGC4Z sample exhibited balanced improvements in mechanical properties, translucency, tribological resistance, and biological safety, while suppressing LTD through microstructural refinement, stress engineering, and crystallization control. Significance This study overcomes the limitations of conventional processing routes by integrating DLP 3D printing technolo","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":" ","pages":""},"PeriodicalIF":6.3,"publicationDate":"2026-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147758584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anisotropic three-dimensional titanium nanospike architectures drive matrix mineralization of human cementoblast-like cells through biophysical cues.","authors":"Kippei Ogumi, Masahiro Yamada, Koki Otake, Takayuki Ohtake, Jun Watanabe, Hiroshi Egusa","doi":"10.1016/j.dental.2026.04.012","DOIUrl":"https://doi.org/10.1016/j.dental.2026.04.012","url":null,"abstract":"<p><strong>Objective: </strong>Regenerating cementum remains a major unmet challenge in periodontal and peri-implant therapy, underscoring the need to understand how cementoblasts respond to engineered surface cues. This study examined the manner in which titanium nanosurfaces integrating anisotropic nanopatterns with three-dimensional (3D) nanospike architectures regulate mechanotransduction and matrix mineralization in human cementoblast-like cells (hCEM).</p><p><strong>Methods: </strong>Titanium surfaces with isotropic, anisotropic, and 3D anisotropic nanospike architectures were fabricated and characterized through quantitative analyses of nanoscale geometry and topographical organization. Surface chemistry and crystallinity were characterized using Fourier transform infrared spectroscopy, grazing-incidence X-ray diffraction, and X-ray photoelectron spectroscopy. hCEM cultures on each surface were evaluated for extracellular calcium (Ca) and phosphate (P) levels, Ca/P ratios, extracellular matrix crystallinity, cytomorphology, and phosphate metabolism-associated gene expression. Mechanotransduction activity was assessed through focal adhesion-Hippo pathway signaling. Relationships between nanoscale architecture, cell stimulation, morphology, and mineralization were examined using correlation and path analyses.</p><p><strong>Results: </strong>Despite comparable wettability and oxide chemistry to that of other nanosurfaces, 3D anisotropic nanospike surfaces produced the highest mineralization and exhibited the highest Ca/P ratios, clear hydroxyapatite signatures, pronounced extracellular nodules, and coordinated activation of phosphate metabolism gene profiles. These surfaces induced prominent nanoscale vertex-cell interactions and distinct cytomorphological responses. Mineralization did not show association with vertical roughness, hydroxyl content, or crystallographic features but positively correlated (r = 0.94) with composite nanoscale architectural metrics capturing spatial heterogeneity and vertex density.</p><p><strong>Significance: </strong>The finding that anisotropic 3D nanospike architectures are associated with enhanced matrix mineralization in human cementoblast-like cells under osteogenic conditions provides mechanistic insight into how nanoscale architecture modulates mineralization responses and may inform the design of cementum-targeted bioactive titanium surfaces.</p>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":" ","pages":""},"PeriodicalIF":6.3,"publicationDate":"2026-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147809210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical properties and antibacterial efficacy against Streptococcus mutans biofilms of novel bioactive tooth root coatings in tooth-brushing simulation.","authors":"Nader Almutairi, Mohammad Alenizy, Ibrahim Ba-Armah, Heba Alqarni, Yazeed Altamimi, Ayman Altamimi, Dwayne D Arola, Mary Anne S Melo, Emily Chu, Jirun Sun, Michael D Weir, Hockin H K Xu","doi":"10.1016/j.dental.2026.04.015","DOIUrl":"https://doi.org/10.1016/j.dental.2026.04.015","url":null,"abstract":"<p><strong>Objectives: </strong>The aging population is retaining more natural teeth, increasing the prevalence of exposed root surfaces. These surfaces are prone to abrasion, erosion, and biofilm accumulation, leading to tissue loss, hypersensitivity, and root caries. The objectives of this study were to: (1) evaluate the surface and mechanical properties of experimental resin coatings containing dimethylaminohexadecyl methacrylate (DMAHDM) and nanoparticles of amorphous calcium phosphate (NACP) following simulated toothbrushing, and (2) assess their antibacterial efficacy and protective effects compared with commercial controls.</p><p><strong>Methods: </strong>Experimental groups with urethane dimethacrylate (UDMA)/ triethylene glycol divinylbenzyl ether (TEGDVBE)+ 5% DMAHDM+ 10% (EX1) or 20% NACP (EX2), along with commercial controls (Seal&Protect and Vanish XT), were tested. Sound and artificially-demineralized dentin served as controls. Hardness, surface roughness, surface loss, and water contact angle were assessed before and after 10,000 brushing cycles. Additionally, Streptococcus mutans (S. mutans) biofilm colony-forming units (CFU) was measured, and surface morphology was evaluated using SEM.</p><p><strong>Results: </strong>EX2 and Seal&Protect had similar hardness (0.12 ± 0.01)GPa (n = 5, p > 0.05), while the hardness values of EX1 and demineralized dentin were lower (0.09 ± 0.01)GPa and (0.07 ± 0.01)GPa (p < 0.05). After 10,000 cycles of brushing, EX1, EX2, and Seal&Protect maintained smooth surfaces (R_a=0.4-0.5 µm; n = 6, p > 0.05), whereas Vanish and uncoated dentin became rougher (R_a=2.0 ± 0.5 µm; p < 0.05). Surface loss after 10,000 cycles was minimal for experimental coatings (0.39-0.55 µm) and comparable to Seal&Protect (2.63 µm), while Vanish (8.42 µm) and dentin controls (19-27 µm) showed significantly greater loss (p < 0.05). Both experimental coatings reduced S. mutans biofilm CFU counts by 7 log, compared to all other groups (p < 0.05), while retaining hydrophobicity. SEM showed intact coatings in the experimental groups and in Seal&Protect, but Vanish and uncoated samples exhibited cracking and dentin exposure.</p><p><strong>Significance: </strong>The DMAHDM-NACP UDMA/TEGDVBE resin coating demonstrated surface and mechanical properties comparable to Seal&Protect and superior surface stability compared to Vanish XT, while achieving potent antibacterial activity not observed in either commercial control. These findings indicate strong potential for this multifunctional resin coating to protect tooth root dentin via physical shielding and sustained antibacterial performance.</p>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":" ","pages":""},"PeriodicalIF":6.3,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147758485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fatigue fracture resistance of a short fiber-reinforced flowable resin composite in single-layer and incremental-layer blocks.","authors":"Shuhei Watanabe, Toshiki Takamizawa, Yuta Kasahara, Shunichi Suda, Kotone Ikeda, Ryo Ishii, Mark A Latta, Masashi Miyazaki","doi":"10.1016/j.dental.2026.04.011","DOIUrl":"https://doi.org/10.1016/j.dental.2026.04.011","url":null,"abstract":"<p><strong>Objectives: </strong>The purpose of this study was to evaluate the effect of a short fiber-reinforced flowable resin composite (SFRFC) on fracture resistance when used as a base material in an incremental layering technique, and to compare it with bulk-fill flowable resin composites (BFRCs).</p><p><strong>Methods: </strong>Seven commercially available flowable resin composites were evaluated: one SFRFC (everX Flow; EFB), three Bulk fill flowable resin composites without fiber reinforcement: (Beautifil-Bulk Flowable; BBF, Omnichroma Flow Bulk; OFB, and SDR flow+ Bulk Fill Flowable; SDR), and three different types of conventional flowable resin composite (Gracefil ZeroFlo; GZ, Beautifil Unishade Flow; BU, and Omnichroma Flow; OU). Flexural strength, flexural modulus, and resilience modulus were measured using a three-point bending test. A fatigue flexural strength test was performed using repeated subcritical load stress at 20 Hz for 50,000 cycles. Additionally, Knoop hardness and wear resistance were evaluated for each individual composite.</p><p><strong>Results: </strong>The incremental-layer group tended to show higher flexural strength, resilience modulus, and fatigue flexural strength than the corresponding individual flowable resin composites. The combination of GZ and the SFRFC EFB showed a significantly higher flexural strength, resilience modulus, and fatigue flexural strength than the other combinations of flowable resin composites. Knoop hardness was material dependent, and GZ exhibited significantly higher wear resistance than the other materials in the simulated localized wear test.</p><p><strong>Significance: </strong>The combination of SFRFC and conventional flowable resin composite GZ appears to be the optimal material strategy for the incremental-layer technique using flowable resin composites, specifically offering superior mechanical properties and fracture resistance against external forces.</p>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":" ","pages":""},"PeriodicalIF":6.3,"publicationDate":"2026-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147758508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical and histopathological evaluation of osteointegration of dental implant fabricated from geopolymer reinforced by boron nitride nanoplatelets. An in vivo study.","authors":"Hasanen Ali AlNamel, Hikmat Jameel Abdul-Baqi, Julfikar Haider","doi":"10.1016/j.dental.2026.04.009","DOIUrl":"https://doi.org/10.1016/j.dental.2026.04.009","url":null,"abstract":"<p><p>A major factor influencing the success of dental implants is osseointegration. The optimum conditions for osseointegration are intimate contact between the bones and the implant bioactive material without an intervening space in association with the aesthetic criteria and the mechanical properties of the dental implant replacing a missing tooth. This study concentrates on assessing the microstructural, biomechanical and biological behavior of geopolymer dental implants after reinforcement with bioactive boron nitride nanoplatelets (BNNPs). Dental implant samples were prepared from alkaline-based geopolymer (kaolinite, aluminum silicate) with Na₂O at a molar ratio of 1, Al₂O₃ at a molar ratio of 1, and SiO₂ at a molar ratio of 4 as the standard group of the study material. BNNPs were added to reinforce the geopolymer at concentrations of 1.0 wt% and 2.0 wt%. The pure geopolymer, BNNPs and reinforced geopolymers were characterized via X-ray diffraction (XRD) to determine the composition and purity of the experimental materials for use as standard dental implants. Microstructural characterization of the samples was performed by scanning electron microscopy (SEM) to examine the surface features of the reinforced geopolymer. An MTT assay was used to measure cellular metabolic activity as an indicator of cell viability, proliferation and cytotoxicity. For the mechanical push-out test and histopathological evaluation, ninety (90) samples were prepared and implanted in the left and right femurs of thirty (30) healthy male New Zealand rabbits, and the animals were divided into 15 rabbits for each test period (2 and 6 weeks). Each division (15 rabbits) was further subdivided into ten rabbits for the push-out mechanical test (shear bond strength), and the other five rabbits were subjected to histological examination. Each rabbit received three implants on the basis of the ratio of BNNP reinforcement: Group 1 with 0.0 wt% BNNP reinforcement (control group), Group 2 with 1.0 wt% BNNP reinforcement and Group 3 with 2.0 wt% BNNP. Each group included 15 samples, 10 samples for biomechanical testing and 5 samples for histological testing. The results revealed that both the control and the reinforced samples presented a greater percentage of viable cells on the first day, followed by a decrease in viability after 7 days. However, the cell viability of the reinforced samples was greater on both day 1 and day 7. Shear bond strength increased significantly among the tested groups at each time interval (2 and 6 weeks). The significant difference between the control group and the reinforced groups after 6 weeks was related to new bone formation adjacent to the implants, as revealed by the histological analysis. Therefore, BNNP reinforced geopolymer could be considered a future dental implant material with the potential for improved osteointegration.</p>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":" ","pages":""},"PeriodicalIF":6.3,"publicationDate":"2026-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147715511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of mechanical reinforcement using nano-clay and acrylic impact modifiers on PMMA denture base: Evaluating single and hybrid additives.","authors":"Daniyal Farajpour, Javad Akbardoost, Mohammad Atai","doi":"10.1016/j.dental.2026.04.006","DOIUrl":"https://doi.org/10.1016/j.dental.2026.04.006","url":null,"abstract":"<p><strong>Objectives: </strong>Denture base fractures are a common clinical problem due to the inherent brittleness and low fracture toughness of polymethyl methacrylate (PMMA). This study assessed whether incorporating nanoscale clay particles and acrylic impact modifiers (AIM) could improve the mechanical properties (fracture toughness, flexural strength, elastic modulus) of PMMA denture base resin.</p><p><strong>Methods: </strong>PMMA specimens were prepared with varying weight percentages of nanoclay and AIM, individually and in combination. Fracture toughness, flexural strength, and elastic modulus were measured using standard mechanical tests (notched-beam and three-point bending). Microstructural features were examined by scanning electron microscopy (SEM). Data were analyzed using one-way analysis of variance (ANOVA) and Tukey's post-hoc test (α = 0.05).</p><p><strong>Results: </strong>AIM alone (2% by weight) increased fracture toughness by 39% (to approximately 2.07 MPa·m^1/2, p ≤ 0.05) compared to unmodified PMMA. Nanoclay at 0.25 wt% (0.25% by weight) also improved fracture toughness; higher nanoclay contents reduced it. Hybrid reinforcements yielded modest fracture toughness gains at optimal combinations but did not improve flexural strength. All reinforced samples showed slightly lower flexural strength than unmodified PMMA. SEM revealed uniform dispersion of additives and toughening interactions at the polymer-additive interfaces.</p><p><strong>Significance: </strong>The marked increase in fracture toughness suggests to enhance the resistance of PMMA against the crack propagation and impact failure in reinforced PMMA. In clinical use, this enhanced fracture toughness may improve resistance to accidental impacts or high-load fractures. These modifications could extend the service life and improve the clinical durability of acrylic denture bases, despite a minor trade-off in flexural strength.</p>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":" ","pages":""},"PeriodicalIF":6.3,"publicationDate":"2026-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147715463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wear resistance of composite repairs: Direct vs. semi-direct techniques in simulated oral aging.","authors":"Keyi Wu, Jaisson Cenci, Roderick Theunisz, Niels van Nistelrooij, X Frank Walboomers, Bas A C Loomans, Tatiana Pereira-Cenci","doi":"10.1016/j.dental.2026.04.010","DOIUrl":"https://doi.org/10.1016/j.dental.2026.04.010","url":null,"abstract":"<p><strong>Objectives: </strong>Wear resistance of composite repairs, especially under severe chemical-mechanical challenge, has not been investigated. This in vitro study evaluated the wear resistance of composite restorations repaired using different techniques in simulated oral aging.</p><p><strong>Methods: </strong>Sixty human molars with direct Mesio-occluso-distal composite restorations were aged in the \"Rub&Roll\" device simulating two years of clinical service. The restorations were repaired using direct (n = 29) or semi-direct (n = 29) techniques. Specimens were randomly divided into three aging media for an additional two-year simulation: deionized water (control), 1% citric acid solution (chemical-mechanical challenge), and yellow millet seed solution (mechanical challenge). Wear was assessed using profilometry and 3D scan. t-test, two-way ANOVA, and multiple linear regression were used for statistical analysis. p < 0.05 was considered statistically significant.</p><p><strong>Results: </strong>After repair, neither repair technique significantly influenced height or volume loss of specimens. The chemical-mechanical challenge had the greatest impact on height loss (coefficient = 0.11, 95% CI: 0.06-0.17 mm, p < 0.001) and volume loss (coefficient = 0.23, 95% CI: 0.13-0.32 mm³, p < 0.001) of specimens. The effect of techniques on height loss of repaired restorations was not significant. However, challenges affected height loss, with chemical-mechanical challenge showing the highest height loss (coefficient = 0.21, 95% CI: 0.16-0.28 mm, p < 0.001).</p><p><strong>Significance: </strong>The wear resistance of repaired composite restorations was not influenced by the repair technique. Instead, chemical-mechanical factors, were the primary determinants of wear, underscoring their critical role in the longevity of tooth-restoration complexes.</p>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":" ","pages":""},"PeriodicalIF":6.3,"publicationDate":"2026-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147715421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical and biological properties of two new commercial PEEK framework materials for fixed and removable dental prostheses compared to unfilled PEEK: An in vitro study.","authors":"Jamila Yassine, Barwin Mahmoud, Franziska Schmidt, Florian Beuer, Rafik Akhmad, Zhen Mao, Wolf-Dieter Müller, Andreas Dominik Schwitalla","doi":"10.1016/j.dental.2026.04.005","DOIUrl":"https://doi.org/10.1016/j.dental.2026.04.005","url":null,"abstract":"<p><strong>Objectives: </strong>The aim of the study was to characterize a novel commercially available PEEK compound reinforced with inorganic fillers for fixed implant-supported dentures in two different shades (beige: Compound B; red: Compound R).</p><p><strong>Methods: </strong>Compound blanks were milled into standardized specimens and polished. Surface characteristics were assessed via contact profilometry (Ra), water contact angle (WCA), and Vickers microhardness at three force levels (HV1, HV0.5, HV0.2). Particle morphology and size distribution were analyzed through scanning electron microscopy and quantified using Fiji software. Flexural properties were evaluated via 3-point bending tests using small bars (1 mm × 2 mm × 15 mm), and compressive properties were determined using cylindrical samples (4 mm × 8 mm). Biocompatibility was evaluated according to ISO 10993-5 using immortalized human gingival fibroblasts (iHGF) and mouse calvaria pre-osteoblasts (MC3T3-E1) through CCK-8 and live/dead fluorescence assays to confirm the absence of cytotoxic effects.</p><p><strong>Results: </strong>Both compounds exhibited excellent polishability (Ra < 0.1 µm) and hydrophobic surface characteristics (WCA ∼80°). Compound R displayed significantly higher flexural strength (194.64 ± 15.44 MPa) and at the same time significantly lower flexural modulus (3.97 ± 0.45 GPa) than Compound B (172.6 ± 12.22 MPa and 4.3 ± 0.41 GPa respectively). Both compounds showed comparable compressive strengths and compressive moduli (171.01 ± 3.54 MPa (Compound B) and 172.3 ± 2.45 MPa (Compound R) and 5.53 ± 0.75 GPa (Compound B) and 5.96 ± 0.22 GPa (Compound R), respectively). Both compounds showed no cytotoxic effects in cell culture, demonstrating biocompatibility comparable to unfilled PEEK.</p><p><strong>Significance: </strong>The investigated PEEK materials demonstrated superior stiffness without compromising flexural strength, outperforming unfilled PEEK and conventional fiber-reinforced PEEK in terms of polishability and esthetics with comparable biocompatibility to unfilled PEEK. The findings suggest that the compounds could represent viable alternative prosthetic framework materials for fixed implant-supported restorations.</p>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":" ","pages":""},"PeriodicalIF":6.3,"publicationDate":"2026-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147715483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}