Dental Materials最新文献

{"title":"Dodecylmethylaminoethyl methacrylate inhibits Enterococcus faecalis in a pH-dependent manner","authors":"Tiantian Shan ,&nbsp;Yiling Li ,&nbsp;Biao Ren ,&nbsp;Wenpan Xian ,&nbsp;Ding Chen ,&nbsp;Xiao Guo ,&nbsp;Bolei Li ,&nbsp;Lei Cheng","doi":"10.1016/j.dental.2024.07.030","DOIUrl":"10.1016/j.dental.2024.07.030","url":null,"abstract":"<div><h3>Objectives</h3><p>Considering the correlation between survival microenvironment of <em>E. faecalis</em> and acidic pH value, this study aimed to investigate the potential of utilizing pH-responsive DMAEM monomers and their copolymers with resin-based root canal sealers to inhibit <em>E. faecalis</em>.</p></div><div><h3>Methods</h3><p>Broth microdilution assay, crystal violet staining and qPCR were performed to evaluate antibacterial effects of DMAEM monomers against <em>E. faecalis</em> at different pH. Methacrylate-resin based root canal sealers were prepared and copolymerized with DMAEM. The flow, solubility, water sorption, apical sealing ability and cytotoxicity of sealers were investigated to optimize formulation. The anti<em>-E. faecalis</em> effects of DMAEM copolymers with sealers were evaluated by direct contact test, colony-forming unit counting and live/dead staining.</p></div><div><h3>Results</h3><p>DMAEM monomers inhibited the growth, biofilm formation and virulence factors expression of <em>E. faecalis</em> in a concentration- and pH-dependent manner. Incorporation of 1.25 % and 2.5 % DMAEM into experimental sealers would not affect the flowability, solubility and periapical sealing ability (<em>P</em> &gt; 0.05), but increased the water sorption of sealers (<em>P</em> &lt; 0.01). Cells viability was higher than 90 % in both 1.25 % and 2.5 % DMAEM groups at pH 7.0. DMAEM copolymers with sealers reduced <em>E. faecalis</em> counts, inhibited biofilm formation and decreased live cells within the biofilm in response to pH values.</p></div><div><h3>Significance</h3><p>DMAEM monomers and their copolymers with resin-based sealers possessed antibacterial and antibiofilm effects on <em>E. faecalis</em> in response to pH values. DMAEM is promising to inhibit intraradicular <em>E. faecalis</em> in response to its acidic survival environment and maintain low cytotoxicity under neutral conditions, ensuring their biosafety in case of inadvertent entry into periapical tissues.</p></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 10","pages":"Pages 1658-1668"},"PeriodicalIF":4.6,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141873765","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":"Bridging instrumental and visual perception with improved color difference equations: A multi-center study","authors":"Sascha Hein ,&nbsp;Omnia Saleh ,&nbsp;Changjun Li ,&nbsp;Julian Nold ,&nbsp;Stephen Westland","doi":"10.1016/j.dental.2024.07.003","DOIUrl":"10.1016/j.dental.2024.07.003","url":null,"abstract":"<div><h3>Objectives</h3><p>This multicenter study aimed to evaluate visual-instrumental agreement of six color measurement devices and optimize three color difference equations using a dataset of visual color differences (∆V) from expert observers.</p></div><div><h3>Methods</h3><p>A total of 154 expert observers from 16 sites across 5 countries participated, providing visual scaling on 26 sample pairs of artificial teeth using magnitude estimation. Three color difference equations (Δ<em>E</em>*_ab, ∆<em>E</em>₀₀, and CAM16-UCS) were tested. Optimization of all three equations was performed using device-specific weights, and the standardized residual sum of squares (<em>STRESS</em>) index was used to evaluate visual-instrumental agreement.</p></div><div><h3>Results</h3><p>The Δ<em>E</em>*_ab formula exhibited <em>STRESS</em> values from 18 to 40, with visual-instrumental agreement between 60 % and 82 %. The ∆<em>E</em>₀₀ formula showed <em>STRESS</em> values from 26 to 32, representing visual-instrumental agreement of 68 % to 74 %. CAM16-UCS demonstrated <em>STRESS</em> values from 32 – 39, with visual-instrumental agreement between 61–68 %. Following optimization, <em>STRESS</em> values decreased for all three formulas, with Δ<em>E</em>^’ demonstrating average visual-instrumental agreement of 79 % and ∆<em>E</em>₀₀ of 78 %. CAM16-UCS showed average visual-instrumental agreement of 76 % post optimization.</p></div><div><h3>Significance</h3><p>Optimization of color difference equations notably improved visual-instrumental agreement, overshadowing device performance. The optimzed Δ<em>E</em>^’ formula demonstrated the best overall performance combining computational simplicty with outstanding visual-instrumental agreement.</p></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 10","pages":"Pages 1497-1506"},"PeriodicalIF":4.6,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0109564124002045/pdfft?md5=5c7d5072aa729b2acffbfd2bc78098fb&pid=1-s2.0-S0109564124002045-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141878064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Micromechanical modelling for bending behaviour of novel bioinspired alumina-based dental composites","authors":"Urangua Jargalsaikhan ,&nbsp;Hongbo Wan ,&nbsp;Nathanael Leung ,&nbsp;Xu Song ,&nbsp;Jianan Hu ,&nbsp;Bo Su ,&nbsp;Tan Sui","doi":"10.1016/j.dental.2024.07.024","DOIUrl":"10.1016/j.dental.2024.07.024","url":null,"abstract":"<div><p>The clinical failure mode of dental crown ceramics involves radial cracking at the interface, driven by the surface tension generated from the flexure of the ceramic layer on the subsurface. This results in a reduced lifespan for most all-ceramic dental crowns. Therefore, investigating optimal material combinations to reduce stress concentration in dental crown materials has become crucial for future successful clinical applications. The anisotropic complex structures of natural materials, such as nacre, could potentially create suitable strong and damage-resistant materials. Their imitation of natural structural optimisation and mechanical functionality at both the macro- and micro-levels minimises weaknesses in dental crowns. This research aims to optimise cost-effective, freeze-casted bioinspired composites for the manufacture of novel, strong, and tough ceramic-based dental crowns. To this end, multilayer alumina (Al₂O₃) composites with four different polymer phases were tested to evaluate their bending behaviour and determine their flexural strength. A computational model was developed and validated against the experimental results. This model includes Al₂O₃ layers that undergo gentle compression and distribute stress, while the polymer layers act as stress relievers, undergoing plastic deformation to reduce stress concentration. Based on the experimental data and numerical modelling, it was concluded that these composites exhibit variability in mechanical properties, primarily due to differences in microstructures and their flexural strength. Furthermore, the findings suggest that bioinspired Al₂O₃-based composites demonstrate promising deformation and strengthening behaviour, indicating potential for application in the dental field.</p></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 10","pages":"Pages 1669-1676"},"PeriodicalIF":4.6,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0109564124002252/pdfft?md5=b38d57463d1b58802e1520ce2ae079f2&pid=1-s2.0-S0109564124002252-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141878066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bis-EMA/Bis-GMA ratio effects on resin-properties and impregnated fiber-bundles","authors":"Muhanad M. Hatamleh ,&nbsp;Adilson Yoshio Furuse","doi":"10.1016/j.dental.2024.07.001","DOIUrl":"10.1016/j.dental.2024.07.001","url":null,"abstract":"<div><h3>Objectives</h3><p>To evaluate the effect of different ratios of Bis-EMA/Bis-GMA resin mixtures on the inherent viscosity and curing-related properties: including degree of cure (DC%), shrinkage strain, Knoop micro-hardness (KH) and flexural strength of resin-impregnated fiber-bundles.</p></div><div><h3>Methods</h3><p>Bis-EMA/Bis-GMA monomers were mixed (by weight) in the following ratios: M1 = 30 %/70 %, M2 = 50 %/50 %, M3 = 70 %/30 %, and M4 = 100 %/0 %. Standard measurements were made of refractive index, viscosity, degree of conversion, shrinkage strain and Knoop hardness (KHN). For 60 % glass fiber-bundles impregnated with 40 % resin, three-point bending test for flexural strength and shrinkage strain were measured. Data were analyzed by One-way ANOVA and Bonferroni <em>post-hoc</em> tests (α = 0.05).</p></div><div><h3>Results</h3><p>For resin mixtures, increasing Bis-EMA proportion decreased refractive index (p &lt; 0.05), and viscosity (p &lt; 0.05), and increased monomer conversion (DC%), shrinkage strain and KHN (p &lt; 0.05). DC% increased after 1 h for all resin mixtures. The shrinkage strain and flexural strength of resin-impregnated fiber-bundles reduced with increased Bis-EMA.</p></div><div><h3>Significance</h3><p>Monomeric mixtures with highest amounts of Bis-EMA showed enhancement in several clinically-relevant properties and polymerization of respective resin-impregnated glass fibers. This makes them potential candidates for impregnating glass fibers in fiber-reinforced restorations.</p></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 10","pages":"Pages 1652-1657"},"PeriodicalIF":4.6,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141858525","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":"Synthesis and challenges of fluorinated divinyl urethane monomers as a strategy for masking hydrolytic sensitive methacrylate groups in resin composites","authors":"Michael Lagowski ,&nbsp;Zach Gouveia ,&nbsp;Meilin Yang ,&nbsp;Yoav Finer ,&nbsp;J.Paul Santerre","doi":"10.1016/j.dental.2024.07.006","DOIUrl":"10.1016/j.dental.2024.07.006","url":null,"abstract":"<div><h3>Objective</h3><p>The biodegradation of methacrylate (MA)-based dental restoratives has been suggested to contribute to a loss of adhesion and subsequent detachment, or secondary caries, both major causes of restoration failure. Previous studies have demonstrated that intermolecular interactions between resin monomers may affect the hydrolytic-susceptibility of composites. Altering the intermolecular interactions by shielding or masking the hydrolytically-susceptible ester groups found in MA monomers could be an effective strategy to mitigate the biodegradation of resin composites. The objective of this work was to assess whether shielding/masking MAs using fluorinated groups could improve the biostability of experimental composites.</p></div><div><h3>Methods</h3><p>Eight fluorinated monomers (FM) were synthesized, characterized (¹H NMR), and formulated into experimental resin composites (FC, 65 wt%, microfill). FCs were assessed for interactions with water (water contact angle, water sorption, gel fraction), mechanical properties (both compressive and flexural strength and modulus), cytocompatibility, resistance to biodegradation using simulated human salivary esterase (SHSE) and compared to a control composite (CC) without FM.</p></div><div><h3>Results</h3><p>Integration of FMs was found to generally decrease both the physical and mechanical properties under all incubation conditions when compared to the CC. Additionally, all FCs had a negative influence on composite biodegradation following immersion in SHSE when compared to the CC.</p></div><div><h3>Significance</h3><p>Shielding/masking MA-esters inherently inserts molecular spaces between the polymer chains within the resin network, and shielding is likely not possible while also maintaining the necessary cohesive forces that regulate the physical and mechanical properties of resin composites. Novel dental resin development should seek to remove/replace vulnerable ester-containing MAs rather that adopting a shielding/masking approach.</p></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 10","pages":"Pages 1624-1634"},"PeriodicalIF":4.6,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0109564124002112/pdfft?md5=7e950bf045384d069b52612329097167&pid=1-s2.0-S0109564124002112-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141858527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and optimization of a novel patient-specific subperiosteal implant additively manufactured in yttria-stabilized zirconia","authors":"Gunpreet Oberoi ,&nbsp;Erik Kornfellner ,&nbsp;Daniel Alexander Aigner ,&nbsp;Ewald Unger ,&nbsp;Martin Schwentenwein ,&nbsp;Daniel Bomze ,&nbsp;Christoph Staudigl ,&nbsp;Dieter Pahr ,&nbsp;Francesco Moscato","doi":"10.1016/j.dental.2024.07.008","DOIUrl":"10.1016/j.dental.2024.07.008","url":null,"abstract":"<div><h3>Objective</h3><p>To design a patient-specific subperiosteal implant for a severely atrophic maxillary ridge using yttria-stabilized additively manufactured zirconia (3YSZ) and evaluate its material properties by applying topology optimization (TO) to replace bulk material with a lattice structure.</p></div><div><h3>Materials</h3><p>A contrast-based segmented skull model from anonymized computed tomography data of a patient was used for the initial anatomical design of the implant for the atrophic maxillary ridge. The implant underwent finite element analysis (FEA) and TO under different occlusal load-bearing conditions. The resulting implant designs, in bulk material and lattice, were evaluated via in-silico tensile tests and 3D printed.</p></div><div><h3>Results</h3><p>The workflow produced two patient-specific subperiosteal designs: a) an anatomically precise bulk implant, b) a TO lattice implant. In-silico tensile tests revealed that the Young’s modulus of yttria-stabilized zirconia is 205 GPa for the bulk material and 83.3 GPa for the lattice. Maximum principal stresses in the implant were 61.14 MPa in bulk material and 278.63 MPa in lattice, both tolerable, indicating the redesigned implant can withstand occlusal forces of 125–250 N per abutment. Furthermore, TO achieved a 13.10 % mass reduction and 208.71 % increased surface area, suggesting improved osteointegration potential.</p></div><div><h3>Significance</h3><p>The study demonstrates the planning and optimization of ceramic implant topology. A further iteration of the implant was successfully implanted in a patient-named use case, employing the same fabrication process and parameters.</p></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 10","pages":"Pages 1568-1574"},"PeriodicalIF":4.6,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0109564124002136/pdfft?md5=9e3ec24f1bfea8198f564ca1ab6d7e4c&pid=1-s2.0-S0109564124002136-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141858526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conventionally and digitally fabricated removable complete dentures: manufacturing accuracy, fracture resistance and repairability","authors":"Adrian Zahel ,&nbsp;Ariadne Roehler ,&nbsp;Pablo Kaucher-Fernandez ,&nbsp;Sebastian Spintzyk ,&nbsp;Frank Rupp ,&nbsp;Eva Engel","doi":"10.1016/j.dental.2024.07.022","DOIUrl":"10.1016/j.dental.2024.07.022","url":null,"abstract":"<div><h3>Objectives</h3><p>Conventionally and digitally manufactured removable complete dentures with different dentition forms were examined for manufacturing accuracy (trueness, precision), fracture forces under torsional loading and subsequent repairability.</p></div><div><h3>Methods</h3><p>A total of 90 mandibular prostheses were manufactured. Ten were made using the injection molding technique and finished with prefabricated teeth. 40 bases each, were manufactured subtractively and additively. Digitally the prosthesis’ dental arch was divided either into two quadrants or three sextants, or kept as full arch. Afterwards, ten additive and subtractive bases were finished with prefabricated teeth and ten of each with milled quadrants, sextants and full arches. After manufacturing, all specimens were rescanned for accuracy comparisons using the Root Mean Square (RMS). Lastly, all specimens were tested to failure under torsional loading.</p></div><div><h3>Results</h3><p>Conventionally manufactured dentures showed the greatest deviation in accuracy. The type of base manufacturing did not determine the fracture resistance of the prostheses. The dentition form had a significant influence. While prefabricated teeth (86.01 ± 19.76 N) and quadrants (77.89 ± 9.58 N) showed a low fracture resistance, sextants (139.12 ± 21.41 N) and full arches (141.05 ± 17.14 N) achieved the highest fracture forces. Subtractive bases with prefabricated teeth or quadrants were assessed to be repairable, digital dentures with full arch were assessed as not repairable.</p></div><div><h3>Significance</h3><p>The presented testing set-up is suitable to determine the fracture behavior of dentures rather than of standards. With the possibility of digital design and individual manufacturing, dentures’ mechanical stability can be significantly increased, especially with suitable dentition forms.</p></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 10","pages":"Pages 1635-1642"},"PeriodicalIF":4.6,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0109564124002288/pdfft?md5=5bc51b594c5f29ed6a1d7b975d141994&pid=1-s2.0-S0109564124002288-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141854379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biaxial flexural strength of nanoglass and multiwalled carbon nanotubes reinforced 3D-printed denture base resins and their shear bond strength to 3D-printed and acrylic denture teeth","authors":"Yomna M. Ibrahim ,&nbsp;Pansai A. Mohamed ,&nbsp;Kenda I. Hanno ,&nbsp;Mohamed M. Abdul-Monem","doi":"10.1016/j.dental.2024.07.026","DOIUrl":"10.1016/j.dental.2024.07.026","url":null,"abstract":"<div><h3>Objective</h3><p>Evaluation of biaxial flexural strength (BFS) of nanoglass (NG) and multiwalled carbon nanotubes (MWCNTs) reinforced 3D-printed denture base resins and their shear bond strength (SBS) to 3D-printed and acrylic denture teeth.</p></div><div><h3>Methods</h3><p>Silanized NG and MWCNTs were added to 3D-printed denture base resin to obtain four groups: Control, 0.25 wt% NG, 0.25 wt% MWCNTs, and a combination group with 0.25 wt% of both fillers. All specimens were tested before and after 600 cycles of thermal aging. BFS (n = 88) was tested using disk-shaped specimens (12 ×2 mm) centralized on an O ring in a universal testing machine. Weibull analysis was conducted to assess predictability of failure. SBS (n = 176) was tested for acrylic and 3D-printed denture teeth attached to bar-shaped specimens in a universal testing machine followed by failure mode analysis using stereomicroscope. Two and three-way ANOVA tests followed by Tukey post hoc test were conducted for BFS and SBS. Kruskal-Wallis test compared percent change among groups with subsequent Dunn post hoc test with Bonferroni correction (α = 0.05).</p></div><div><h3>Results</h3><p>BFS was affected significantly by filler content (<em>P</em> &lt; 0.001) and thermal cycling (<em>P</em> &lt; 0.001), with thermal cycling displaying the uppermost effect (Ƞp² =0.551). A significant interaction between filler content, thermal cycling, and teeth type was displayed by SBS results (<em>P</em> &lt; 0.001, F=10.340, Ƞp² =0.162). The highest BFS values belonged to 0.25 % MWCNTs while the highest SBS to printed teeth was displayed by the combination.</p></div><div><h3>Significance</h3><p>The combination group displayed higher BFS and SBS to printed teeth compared to control which allows 3D-printed materials to have a long-term clinical success.</p></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 10","pages":"Pages 1557-1567"},"PeriodicalIF":4.6,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141854377","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":"Monomer elution and shrinkage stress analysis of addition-fragmentation chain-transfer-modified resin composites in relation to the curing protocol","authors":"Donát Szebeni ,&nbsp;Roland Told ,&nbsp;Sándor Kunsági-Máté ,&nbsp;József Szalma ,&nbsp;Péter Maróti ,&nbsp;Katalin Böddi ,&nbsp;Edina Lempel","doi":"10.1016/j.dental.2024.07.029","DOIUrl":"10.1016/j.dental.2024.07.029","url":null,"abstract":"<div><h3>Objective</h3><p>The purpose was to compare the effects of rapid (3 s) and conventional (20 s) polymerization protocols (PP) of mono- and multichip LED curing units (LCU) on shrinkage stress (SS) and monomer elution (ME) in bulk-fill resin-based composites (RBC) with and without addition-fragmentation chain-transfer (AFCT) monomer.</p></div><div><h3>Methods</h3><p>Cylindrical (5x4mm) specimens were prepared from two RBCs containing different AFCT monomers (Filtek OneBulk-FOB; Tetric PowerFill-TPF) and one without (Tetric EvoCeram Bulk-TEC). After soaking for 3, 10, and 14 days (75 % ethanol), ME was quantified using standard monomers by High-Performance Liquid Chromatography. SS was measured from the start of polymerization to 5 min using a Materials Testing Machine. The radiant exitance of LCUs was measured using a spectrophotometer. ANOVA and Tukey's post-hoc test, multivariate analysis and partial eta-squared statistics were used to analyze the data (p &lt; 0.05).</p></div><div><h3>Results</h3><p>AFCT-modification significantly decreased ME (p &lt; 0.001). ME was reduced by half by day 10 and by one tenth by the end of the 14-day compared to the 3-day sampling. ME itself was dependent, whereas the percentage of monomers released was independent of the PP used (p &gt; 0.05). FOB showed the lowest SS (p &lt; 0.001), while there was no significant difference between TPF and TEC (p = 0.124). Both ME and SS were significantly influenced by material type and PP.</p></div><div><h3>Significance</h3><p>The incorporation of the AFCT monomer reduced ME, but this was inversely related to a decrease in exposure time. SS values reduced by rapid PP in parallel with increasing ME values. The utilization of the AFCT molecule in conjunction with an appropriate resin-, initiator-system is of significant consequence for the kinetics of polymerization and the incorporation of monomers into the network.</p></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 10","pages":"Pages 1611-1623"},"PeriodicalIF":4.6,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0109564124002318/pdfft?md5=870100ad6e2008ffd2c6f0ebe43c0d75&pid=1-s2.0-S0109564124002318-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141854381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Composition control of additively manufactured color-graded temporary veneer","authors":"Imam Akbar Sutejo ,&nbsp;Sinuo Zhang ,&nbsp;Chang Woo Gal ,&nbsp;Yeong-Jin Choi ,&nbsp;Honghyun Park ,&nbsp;Sungmin Kim ,&nbsp;Hyung-bong Lim ,&nbsp;Hui-suk Yun","doi":"10.1016/j.dental.2024.07.027","DOIUrl":"10.1016/j.dental.2024.07.027","url":null,"abstract":"<div><h3>Objective</h3><p>The aim of this study was to design and assess composite resin composition for patient-specific esthetic color-graded temporary veneer.</p></div><div><h3>Methods</h3><p>Various compositions of composite structures (assorted by Ba₂SiO₄ filler, TiO₂ pigment, and photoinitiator) were prepared via additive manufacturing with 3 s UV exposure (405 nm, 10 W/cm²) per 50 µm thick layer followed by 20 min post-curing treatment after fabrication. The effect of each component on the generated color shades was observed and compared to the commonly used VITA shade guide. The coloration was explored by staining aging treatment under dry, wet, artificial saliva environments, coffee, and cola. The mechanical properties were also evaluated. Color measurement and comparison were done using a colorimeter (lightness (L*), green-red color (a*), and blue-yellow color (b*)), and the changes were calculated by CIEDE2000 (ΔE₀₀), translucency parameter (TP) and whiteness index (WI_D). The composition color analysis results were then applied to produce a color-graded temporary veneer for mimicking a natural look.</p></div><div><h3>Result</h3><p>Mechanically, all composition result in adequate bending strength with maximum achievable strength of 111.64 MPa. At the same time, the composite color was affected by each constituent differently. The L* value, which indicates the color lightness of the composite, was considerably tuned by the TiO₂ pigment, whereas Ba₂SiO₄ filler only triggered minor changes. Photoinitiator concentration significantly affected the yellowness, indicated by the increased b* value. Similar tendency also observed toward the calculated TP and WI_D as well. Based on these evaluations, color-graded temporary veneer successfully generated, matching the VITA A3, A2, and B1 shades gradation. However, the stability of the composite color decreased at high amounts of Ba₂SiO₄ and photoinitiator.</p></div><div><h3>Significance</h3><p>The study presents a composition guide for fabricating temporary patient-specific color-graded veneer. It provides insights on the effect of the constituent material on dental esthetics.</p></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 10","pages":"Pages 1643-1651"},"PeriodicalIF":4.6,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0109564124002264/pdfft?md5=c8d8d2cc9164e133fa01dc09f7e24ee0&pid=1-s2.0-S0109564124002264-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141854378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}