Pub Date : 2024-12-01DOI: 10.1016/j.dental.2024.11.002
Alex Fok
{"title":"Models for shrinkage stress: C-factor and all that","authors":"Alex Fok","doi":"10.1016/j.dental.2024.11.002","DOIUrl":"10.1016/j.dental.2024.11.002","url":null,"abstract":"","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 12","pages":"Pages 2075-2076"},"PeriodicalIF":4.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142610823","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}
Pub Date : 2024-12-01DOI: 10.1016/j.dental.2024.10.002
Eva Sanchez Armengol , Luis Alberto Sánchez Soler , Noah Valverde Offermann , Flavia Laffleur
The goal of this study was to develop a new poly(methyl methacrylate) (PMMA)-based conjugate with enhanced mucoadhesive features for gingiva. Five MMA-based conjugates with varying amounts of hydroxyethyl maleimide (HEM) and poly(ethylene glycol) (PEG) were synthesized and characterized using infrared spectroscopy and proton nuclear magnetic resonance. Quantification of attached HEM and PEG was performed using assay kits and established protocols. Mucoadhesiveness was tested through rheological measurements, retention time, and tensile strength studies. Results showed successful unification of MMA with HEM and PEG, with varying degrees of modification and no toxic effects. Dynamic viscosity was enhanced up to 13-fold for MMA-100Mal, decreasing incrementally for MMA-75Mal, MMA-50Mal, MMA-25Mal, and MMA-0Mal. Retention time improved up to 120-fold for MMA-100Mal, decreasing to 37.5-fold for MMA-0Mal. Mucoadhesiveness followed the order: MMA-100Mal > MMA-75Mal > MMA-50Mal > MMA-25Mal > MMA-0Mal. In conclusion, the novel modification of MMA with increased mucoadhesive features to buccal gingiva suggests its potential as a long-term total denture base material, paving the way for more patient-friendly prostheses.
{"title":"Polymer powerhouse: Methyl methacrylate – A breakthrough blend for superior adhesion to gingiva","authors":"Eva Sanchez Armengol , Luis Alberto Sánchez Soler , Noah Valverde Offermann , Flavia Laffleur","doi":"10.1016/j.dental.2024.10.002","DOIUrl":"10.1016/j.dental.2024.10.002","url":null,"abstract":"<div><div>The goal of this study was to develop a new poly(methyl methacrylate) (PMMA)-based conjugate with enhanced mucoadhesive features for gingiva. Five MMA-based conjugates with varying amounts of hydroxyethyl maleimide (HEM) and poly(ethylene glycol) (PEG) were synthesized and characterized using infrared spectroscopy and proton nuclear magnetic resonance. Quantification of attached HEM and PEG was performed using assay kits and established protocols. Mucoadhesiveness was tested through rheological measurements, retention time, and tensile strength studies. Results showed successful unification of MMA with HEM and PEG, with varying degrees of modification and no toxic effects. Dynamic viscosity was enhanced up to 13-fold for MMA-100Mal, decreasing incrementally for MMA-75Mal, MMA-50Mal, MMA-25Mal, and MMA-0Mal. Retention time improved up to 120-fold for MMA-100Mal, decreasing to 37.5-fold for MMA-0Mal. Mucoadhesiveness followed the order: MMA-100Mal > MMA-75Mal > MMA-50Mal > MMA-25Mal > MMA-0Mal. In conclusion, the novel modification of MMA with increased mucoadhesive features to buccal gingiva suggests its potential as a long-term total denture base material, paving the way for more patient-friendly prostheses.</div></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 12","pages":"Pages 2101-2113"},"PeriodicalIF":4.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142454521","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}
Pub Date : 2024-11-01DOI: 10.1016/j.dental.2024.09.004
Oscar E. Pecho , Pedro Alvarez-Lloret , Ana M. Ionescu , Juan C. Cardona , Razvan Ghinea , Purificación Sánchez-Sánchez , Maria M. Perez , Alvaro Della Bona
Objectives
To evaluate the influence of microstructure and chemical composition on the optical properties of CAD-CAM lithium disilicate glass-ceramics.
Methods
Samples (n = 5; 1.0 mm thickness) of shades A1, A2, and A3 were fabricated from CAD-CAM ceramic blocks (Ivoclar Vivadent): IPS e.max® CAD LT (emLT) and HT (emHT). Samples were polished to 1.0 ± 0.01 mm in thickness. The optical properties (R- reflectance; T- transmittance; - reduced scattering and - absorption coefficients) from the post-crystallized samples were determined using the inverse adding-doubling (IAD) method based on integrating-sphere measurements. Additionally, scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques were used to evaluate the microstructural properties. Energy-dispersive X-ray (EDX) was employed to analyze the chemical composition. The chemical and structural characterization were performed before and after crystallization of the ceramic samples.
Results
emLT showed higher values of and lower values of and T than emHT for each shade in all wavelengths (p < 0.003). Considering T for emHT, there were no statistical differences for shades A1 and A2 at 488 nm and 514.5 nm (p > 0.003) and shades A1 and A3 at 457.9 nm (p > 0.003). emLT showed particle length ranging from 0.74 to 2.78 µm (mean = 1.57 µm and RF-relative frequency = 28 %) and particle width ranging from 0.21 to 0.74 µm (mean = 0.30 µm and RF = 31 %). emHT showed particle length ranging from 0.83 to 3.08 µm (mean = 1.86 µm and RF = 21 %) and particle width ranging from 0.24 to 1.12 µm (mean = 0.56 µm and RF = 28 %). In comparison with emHT, emLT showed greater vol% for C, K, and Zr and lower vol% for O and Al.
Significance
The optical properties of CAD-CAM lithium disilicate glass-ceramics are influenced by the chemical composition and, consequently, by the material microstructure.
{"title":"Influence of microstructure on optical properties of CAD-CAM lithium disilicate glass-ceramics","authors":"Oscar E. Pecho , Pedro Alvarez-Lloret , Ana M. Ionescu , Juan C. Cardona , Razvan Ghinea , Purificación Sánchez-Sánchez , Maria M. Perez , Alvaro Della Bona","doi":"10.1016/j.dental.2024.09.004","DOIUrl":"10.1016/j.dental.2024.09.004","url":null,"abstract":"<div><h3>Objectives</h3><div>To evaluate the influence of microstructure and chemical composition on the optical properties of CAD-CAM lithium disilicate glass-ceramics.</div></div><div><h3>Methods</h3><div>Samples (n = 5; 1.0 mm thickness) of shades A1, A2, and A3 were fabricated from CAD-CAM ceramic blocks (Ivoclar Vivadent): IPS e.max® CAD LT (emLT) and HT (emHT). Samples were polished to 1.0 ± 0.01 mm in thickness. The optical properties (R- reflectance; T- transmittance; <span><math><msubsup><mrow><mi>μ</mi></mrow><mrow><mi>s</mi></mrow><mrow><mo>′</mo></mrow></msubsup></math></span>- reduced scattering and <span><math><msub><mrow><mi>μ</mi></mrow><mrow><mi>a</mi></mrow></msub></math></span>- absorption coefficients) from the post-crystallized samples were determined using the inverse adding-doubling (IAD) method based on integrating-sphere measurements. Additionally, scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques were used to evaluate the microstructural properties. Energy-dispersive X-ray (EDX) was employed to analyze the chemical composition. The chemical and structural characterization were performed before and after crystallization of the ceramic samples.</div></div><div><h3>Results</h3><div>emLT showed higher values of <span><math><mrow><msubsup><mrow><mi>μ</mi></mrow><mrow><mi>s</mi></mrow><mrow><mo>′</mo></mrow></msubsup><mspace></mspace></mrow></math></span>and lower values of <span><math><msub><mrow><mi>μ</mi></mrow><mrow><mi>a</mi></mrow></msub></math></span> and T than emHT for each shade in all wavelengths (p < 0.003). Considering T for emHT, there were no statistical differences for shades A1 and A2 at 488 nm and 514.5 nm (p > 0.003) and shades A1 and A3 at 457.9 nm (p > 0.003). emLT showed particle length ranging from 0.74 to 2.78 µm (mean = 1.57 µm and RF-relative frequency = 28 %) and particle width ranging from 0.21 to 0.74 µm (mean = 0.30 µm and RF = 31 %). emHT showed particle length ranging from 0.83 to 3.08 µm (mean = 1.86 µm and RF = 21 %) and particle width ranging from 0.24 to 1.12 µm (mean = 0.56 µm and RF = 28 %). In comparison with emHT, emLT showed greater vol% for C, K, and Zr and lower vol% for O and Al.</div></div><div><h3>Significance</h3><div>The optical properties of CAD-CAM lithium disilicate glass-ceramics are influenced by the chemical composition and, consequently, by the material microstructure.</div></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 11","pages":"Pages 1927-1936"},"PeriodicalIF":4.6,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142277763","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}
Pub Date : 2024-11-01DOI: 10.1016/j.dental.2024.08.004
Luciano Madeira , Katia R. Weber , Natan Carpenedo , Yu Zhang , Thiago S. Porto , Josete Barbosa Cruz Meira , Carla C. Gonzaga , Marina R. Kaizer
Objectives
To assess the impact of elastic gradients formed among restorative material, cement, and substrate on the fracture resistance of tri-layer restorative systems.
Methods
Four CAD/CAM materials were utilized, two glass-ceramics (IPS e.max CAD, Vita Suprinity) and two resin-ceramic hybrids (Vita Enamic, Lava Ultimate). Their fracture resistance was examined by biaxial flexure (n = 8) and Hertzian indentation (n = 10) tests. Statistical analysis was conducted using ANOVA and Tukey tests (p = 5 %). Finite element analysis (FEA) was employed to simulate the Hertzian indentation test and elucidate the stress-fields formed on the intaglio surface below the loading area.
Results
The biaxial flexural strength (MPa) of glass-ceramics exceeded the hybrid materials (e.max 417a, Suprinity 230b, Enamic 138c, and Lava Ultimate 183bc). Conversely, the load-bearing capacity (N) of the materials bonded to dentin analog demonstrated the opposite trend, with the hybrid materials achieving superior results (e.max 830 C, Suprinity 660D, Enamic 1822B, and Lava Ultimate 2593 A). The stress-fields observed by FEA were coherent with the experimental results for Hertzian flexural stresses (MPa): e.max 501 A, Suprinity 342 C, Enamic 406B, whereas no tensile stress was observed at the intaglio surface of Lava Ultimate.
Significance
Detailed analysis of the fracture resistance of the tri-layer restorative systems showed that the elastic gradients play a more significant role than the flexural strength of the restorative materials. The coherence of the elastic moduli between the restorative material and supporting structures results in reduced tensile stress concentration at the intaglio surface beneath the loading area and enhances the ability to withstand load.
{"title":"Effect of elastic gradients on the fracture resistance of tri-layer restorative systems","authors":"Luciano Madeira , Katia R. Weber , Natan Carpenedo , Yu Zhang , Thiago S. Porto , Josete Barbosa Cruz Meira , Carla C. Gonzaga , Marina R. Kaizer","doi":"10.1016/j.dental.2024.08.004","DOIUrl":"10.1016/j.dental.2024.08.004","url":null,"abstract":"<div><h3>Objectives</h3><div>To assess the impact of elastic gradients formed among restorative material, cement, and substrate on the fracture resistance of tri-layer restorative systems.</div></div><div><h3>Methods</h3><div>Four CAD/CAM materials were utilized, two glass-ceramics (IPS e.max CAD, Vita Suprinity) and two resin-ceramic hybrids (Vita Enamic, Lava Ultimate). Their fracture resistance was examined by biaxial flexure (<em>n</em> = 8) and Hertzian indentation (<em>n</em> = 10) tests. Statistical analysis was conducted using ANOVA and Tukey tests (p = 5 %). Finite element analysis (FEA) was employed to simulate the Hertzian indentation test and elucidate the stress-fields formed on the intaglio surface below the loading area.</div></div><div><h3>Results</h3><div>The biaxial flexural strength (MPa) of glass-ceramics exceeded the hybrid materials (e.max 417<sup>a</sup>, Suprinity 230<sup>b</sup>, Enamic 138<sup>c</sup>, and Lava Ultimate 183<sup>bc</sup>). Conversely, the load-bearing capacity (N) of the materials bonded to dentin analog demonstrated the opposite trend, with the hybrid materials achieving superior results (e.max 830 <sup>C</sup>, Suprinity 660<sup>D</sup>, Enamic 1822<sup>B</sup>, and Lava Ultimate 2593 <sup>A</sup>). The stress-fields observed by FEA were coherent with the experimental results for Hertzian flexural stresses (MPa): e.max 501 <sup>A</sup>, Suprinity 342 <sup>C</sup>, Enamic 406<sup>B</sup>, whereas no tensile stress was observed at the intaglio surface of Lava Ultimate.</div></div><div><h3>Significance</h3><div>Detailed analysis of the fracture resistance of the tri-layer restorative systems showed that the elastic gradients play a more significant role than the flexural strength of the restorative materials. The coherence of the elastic moduli between the restorative material and supporting structures results in reduced tensile stress concentration at the intaglio surface beneath the loading area and enhances the ability to withstand load.</div></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 11","pages":"Pages 1862-1871"},"PeriodicalIF":4.6,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142102790","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}
Pub Date : 2024-11-01DOI: 10.1016/j.dental.2024.09.001
Håvard J. Haugen , Qianli Ma , Stefanie Linskens , Matej Par , Visnja Negovetic Mandic , Emile Mensikova , Liebert P. Nogueira , Tobias T. Taubock , Thomas Attin , Andrea Gubler , Sander Leeuwenburgh , Michiel Op de Beeck , Danijela Marovic
Background
Dental resin composites' performance is intricately linked to their polymerisation shrinkage characteristics. This study compares polymerisation shrinkage using advanced 3D micro-computed tomography (micro-CT) and traditional 2D linear assessments. It delves into the crucial role of filler content on shrinkage and the degree of conversion in dental resin composites, providing valuable insights for the field.
Methods
Five experimental dental composite materials were prepared with increasing filler contents (55–75 wt%) and analysed using either 3D micro-CT for volumetric shrinkage or a custom-designed linometer for 2D linear shrinkage. The degree of conversion was assessed using Optical Photothermal Infrared (O-PTIR) and Fourier-Transform Infrared (FTIR) spectroscopy. Light transmittance through a 2-mm layer was evaluated using a NIST-calibrated spectrometer. Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray Spectroscopy (EDX) examined surface morphology and elemental distribution. Correlation between the investigated parameters was determined using Spearman correlation analyses.
Results
The study found significant differences in polymerisation-related properties among different filler content categories, with volumetric shrinkage consistently demonstrating higher mean values than linear shrinkage across most groups. Volumetric shrinkage decreased with increasing curing depth, showing no direct correlation between filler content and shrinkage levels at different curing depths. The results highlighted a strong negative correlation between filler content and degree of conversion, volumetric and linear shrinkage, as well as maximum shrinkage rate. Light transmittance showed a moderate correlation with the filler content and a weak correlation with other tested parameters.
Conclusions
This study underscores the importance of considering both volumetric and linear shrinkage in the design and analysis of dental composite materials. The findings advocate optimising filler content to minimise shrinkage and enhance material performance. Integrating micro-CT and O-PTIR techniques offers novel insights into dental composites' polymerisation behaviour, providing a foundation for future research to develop materials with improved clinical outcomes.
{"title":"3D micro-CT and O-PTIR spectroscopy bring new understanding of the influence of filler content in dental resin composites","authors":"Håvard J. Haugen , Qianli Ma , Stefanie Linskens , Matej Par , Visnja Negovetic Mandic , Emile Mensikova , Liebert P. Nogueira , Tobias T. Taubock , Thomas Attin , Andrea Gubler , Sander Leeuwenburgh , Michiel Op de Beeck , Danijela Marovic","doi":"10.1016/j.dental.2024.09.001","DOIUrl":"10.1016/j.dental.2024.09.001","url":null,"abstract":"<div><h3>Background</h3><div>Dental resin composites' performance is intricately linked to their polymerisation shrinkage characteristics. This study compares polymerisation shrinkage using advanced 3D micro-computed tomography (micro-CT) and traditional 2D linear assessments. It delves into the crucial role of filler content on shrinkage and the degree of conversion in dental resin composites, providing valuable insights for the field.</div></div><div><h3>Methods</h3><div>Five experimental dental composite materials were prepared with increasing filler contents (55–75 wt%) and analysed using either 3D micro-CT for volumetric shrinkage or a custom-designed linometer for 2D linear shrinkage. The degree of conversion was assessed using Optical Photothermal Infrared (O-PTIR) and Fourier-Transform Infrared (FTIR) spectroscopy. Light transmittance through a 2-mm layer was evaluated using a NIST-calibrated spectrometer. Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray Spectroscopy (EDX) examined surface morphology and elemental distribution. Correlation between the investigated parameters was determined using Spearman correlation analyses.</div></div><div><h3>Results</h3><div>The study found significant differences in polymerisation-related properties among different filler content categories, with volumetric shrinkage consistently demonstrating higher mean values than linear shrinkage across most groups. Volumetric shrinkage decreased with increasing curing depth, showing no direct correlation between filler content and shrinkage levels at different curing depths. The results highlighted a strong negative correlation between filler content and degree of conversion, volumetric and linear shrinkage, as well as maximum shrinkage rate. Light transmittance showed a moderate correlation with the filler content and a weak correlation with other tested parameters.</div></div><div><h3>Conclusions</h3><div>This study underscores the importance of considering both volumetric and linear shrinkage in the design and analysis of dental composite materials. The findings advocate optimising filler content to minimise shrinkage and enhance material performance. Integrating micro-CT and O-PTIR techniques offers novel insights into dental composites' polymerisation behaviour, providing a foundation for future research to develop materials with improved clinical outcomes.</div></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 11","pages":"Pages 1881-1894"},"PeriodicalIF":4.6,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142277749","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}
Pub Date : 2024-11-01DOI: 10.1016/j.dental.2024.09.007
Bruno Arruda Mascaro , Maria Tejada-Casado , Renata Garcia Fonseca , José Maurício dos Santos Nunes Reis , María M. Pérez
Objectives
To evaluate and compare the optical properties and relative translucency parameter of CAD-CAM restorative materials.
Methods
Four CAD-CAM materials were evaluated: Lava Ultimate (LU), Grandio Blocs (GB), VITA Enamic (VE), and VITA Mark II (VM). Disk-shaped samples in shade A2-HT were prepared (n = 10) and polished to 1.00 ± 0.01 mm of thickness. Scattering (S), absorption (K), albedo (a) coefficient, transmittance (T%), light reflectivity (RI), infinite optical thickness (X∞), and radiative transfer coefficients (μa, and μ′S) were calculated using Kubelka-Munk method and Thennadil's semi-empirical approach. Root Mean Square Error (RMSE) and Goodness of Fit (GFC) were used as performance optical behavior. Translucency differences were evaluated using the relative translucency parameter (RTP00) and 50:50 % translucency perceptibility and acceptability thresholds (TPT00 and TAT00).
Results
The spectral distribution of S, K, T%, RI, and X∞ was wavelength-dependent. GFC and RMSE values indicated good spectral behavior matches and good comparative spectral values for RI in LU-GB, LU-VE, and GB-VE, and for K in VE-VM. VM displayed the highest scattering values across the wavelengths, while VE and VM showed lower absorption at shorter wavelengths. LU and GB had the highest transmittance. The X∞ values indicated that all 1.0 mm thick materials could be influenced by the background. No good spectral match and no good comparative spectral values were found between CAD-CAM materials and anterior bovine maxillary specimens. VM had the lowest RTP00 values with perceptible and unacceptable differences compared to CAD-CAM materials evaluated.
Significance
Understanding the optical behavior of different CAD-CAM materials was essential for guiding clinicians in material selection and optimizing their clinical performance. The findings confirm that the different compositions and microstructure impact the optical properties and translucency of CAD-CAM restorative materials.
{"title":"Exploring the optical behavior and relative translucency parameter of CAD-CAM resin-based composites, polymer-infiltrated ceramic network, and feldspar porcelain","authors":"Bruno Arruda Mascaro , Maria Tejada-Casado , Renata Garcia Fonseca , José Maurício dos Santos Nunes Reis , María M. Pérez","doi":"10.1016/j.dental.2024.09.007","DOIUrl":"10.1016/j.dental.2024.09.007","url":null,"abstract":"<div><h3>Objectives</h3><div>To evaluate and compare the optical properties and relative translucency parameter of CAD-CAM restorative materials.</div></div><div><h3>Methods</h3><div>Four CAD-CAM materials were evaluated: Lava Ultimate (LU), Grandio Blocs (GB), VITA Enamic (VE), and VITA Mark II (VM). Disk-shaped samples in shade A2-HT were prepared (n = 10) and polished to 1.00 ± 0.01 mm of thickness. Scattering (S), absorption (K), albedo (<em>a</em>) coefficient, transmittance (T%), light reflectivity (RI), infinite optical thickness (<em>X</em><sub>∞</sub>), and radiative transfer coefficients (<em>μ</em><sub><em>a</em></sub>, and <em>μ</em>′<sub><em>S</em></sub><em>)</em> were calculated using Kubelka-Munk method and Thennadil's semi-empirical approach. Root Mean Square Error (<em>RMSE</em>) and Goodness of Fit (GFC) were used as performance optical behavior. Translucency differences were evaluated using the relative translucency parameter (RTP<sub>00</sub>) and 50:50 % translucency perceptibility and acceptability thresholds (TPT<sub>00</sub> and TAT<sub>00</sub>).</div></div><div><h3>Results</h3><div>The spectral distribution of S, K, T%, RI, and <em>X</em><sub>∞</sub> was wavelength-dependent. GFC and <em>RMSE</em> values indicated good spectral behavior matches and good comparative spectral values for RI in LU-GB, LU-VE, and GB-VE, and for K in VE-VM. VM displayed the highest scattering values across the wavelengths, while VE and VM showed lower absorption at shorter wavelengths. LU and GB had the highest transmittance. The <em>X</em><sub>∞</sub> values indicated that all 1.0 mm thick materials could be influenced by the background. No good spectral match and no good comparative spectral values were found between CAD-CAM materials and anterior bovine maxillary specimens. VM had the lowest RTP<sub>00</sub> values with perceptible and unacceptable differences compared to CAD-CAM materials evaluated.</div></div><div><h3>Significance</h3><div>Understanding the optical behavior of different CAD-CAM materials was essential for guiding clinicians in material selection and optimizing their clinical performance. The findings confirm that the different compositions and microstructure impact the optical properties and translucency of CAD-CAM restorative materials.</div></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 11","pages":"Pages 1954-1961"},"PeriodicalIF":4.6,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142338150","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}
Pub Date : 2024-11-01DOI: 10.1016/j.dental.2024.09.006
Parmanand Ahirwar , Veronika Kozlovskaya , Piyasuda Pukkanasut , Pavel Nikishau , Sarah Nealy , Gregory Harber , Suzanne M. Michalek , Linto Antony , Hui Wu , Eugenia Kharlampieva , Sadanandan E. Velu
Objectives
The goal of this study is to develop a novel drug delivery platform for the pH-responsive delivery of biofilm inhibitors as a potential avenue to prevent and treat dental caries.
Methods
Biofilm and growth inhibition assays were performed in polystyrene microtiter 96-well plates. Docking analysis was performed using the reported GtfB + HA5 co-crystal structure (PDB code: 8fg8) in SeeSAR 13.0.1 software. Polymersome vesicles were assembled from poly(N-vinylpyrrolidone)8-block-poly(dimethylsiloxane)64-block-poly(N-vinylpyrrolidone)8 (PVPON8-PDMS64-PVPON8) triblock copolymer using a nanoprecipitation method. Microbiome analysis of biofilm inhibitors and the in vivo drug release and antivirulence activities of polymersome encapsulated inhibitors have been carried out in a S. mutans induced rat caries model.
Results
Biofilm inhibitors for HA5 and HA6 have shown species-specific selectivity towards S. mutans and the ability to preserve the oral microbiome in a S. mutans induced dental caries model. The inhibitors were encapsulated into pH-responsive block copolymer vesicles to generate polymersome-encapsulated biofilm inhibitors, and their biofilm and growth inhibitory activities against S. mutans and representative strains of oral commensal streptococci have been assessed. A 4-week treatment of S. mutans UA159 infected gnotobiotic rats with 100 µM of polymersome-encapsulated biofilm inhibitor, PEHA5 showed significant reductions in buccal, sulcal, and proximal caries scores compared to an untreated control group.
Significance
Taken together, our data suggests that the biofilm-selective therapy using the polymersome-encapsulated biofilm inhibitors is a viable approach for the prevention and treatment of dental caries while preserving the oral microbiome.
{"title":"Polymer vesicles for the delivery of inhibitors of cariogenic biofilm","authors":"Parmanand Ahirwar , Veronika Kozlovskaya , Piyasuda Pukkanasut , Pavel Nikishau , Sarah Nealy , Gregory Harber , Suzanne M. Michalek , Linto Antony , Hui Wu , Eugenia Kharlampieva , Sadanandan E. Velu","doi":"10.1016/j.dental.2024.09.006","DOIUrl":"10.1016/j.dental.2024.09.006","url":null,"abstract":"<div><h3>Objectives</h3><div>The goal of this study is to develop a novel drug delivery platform for the pH-responsive delivery of biofilm inhibitors as a potential avenue to prevent and treat dental caries.</div></div><div><h3>Methods</h3><div>Biofilm and growth inhibition assays were performed in polystyrene microtiter 96-well plates. Docking analysis was performed using the reported GtfB + HA5 co-crystal structure (PDB code: 8fg8) in SeeSAR 13.0.1 software. Polymersome vesicles were assembled from poly(N-vinylpyrrolidone)<sub>8</sub>-<em>block</em>-poly(dimethylsiloxane)<sub>64</sub>-<em>block</em>-poly(N-vinylpyrrolidone)<sub>8</sub> (PVPON<sub>8</sub>-PDMS<sub>64</sub>-PVPON<sub>8</sub>) triblock copolymer using a nanoprecipitation method. Microbiome analysis of biofilm inhibitors and the <em>in vivo</em> drug release and antivirulence activities of polymersome encapsulated inhibitors have been carried out in a <em>S. mutans</em> induced rat caries model.</div></div><div><h3>Results</h3><div>Biofilm inhibitors for HA5 and HA6 have shown species-specific selectivity towards <em>S. mutans</em> and the ability to preserve the oral microbiome in a <em>S. mutans</em> induced dental caries model. The inhibitors were encapsulated into pH-responsive block copolymer vesicles to generate polymersome-encapsulated biofilm inhibitors, and their biofilm and growth inhibitory activities against <em>S. mutans</em> and representative strains of oral commensal streptococci have been assessed. A 4-week treatment of <em>S. mutans</em> UA159 infected gnotobiotic rats with 100 µM of polymersome-encapsulated biofilm inhibitor, PEHA5 showed significant reductions in buccal, sulcal, and proximal caries scores compared to an untreated control group.</div></div><div><h3>Significance</h3><div>Taken together, our data suggests that the biofilm-selective therapy using the polymersome-encapsulated biofilm inhibitors is a viable approach for the prevention and treatment of dental caries while preserving the oral microbiome.</div></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 11","pages":"Pages 1937-1953"},"PeriodicalIF":4.6,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142338152","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}
Pub Date : 2024-11-01DOI: 10.1016/j.dental.2024.09.013
Olivia Awino Osiro , Melissa Tiskaya , Saroash Shahid , Robert Graham Hill
Objectives
To evaluate the mechanical properties, fluoride release, radiopacity, and setting characteristics of dental cements derived from highly reactive ionomer glasses and bottle glass mixtures.
Methods
Two highly reactive glass series, LG99 and LG117, were synthesized, milled, sieved, and characterized using XRD and laser particle size analysis. These glasses were mixed with predetermined ratios of ground bottle glass, poly(acrylic acid), and aqueous tartaric acid to form glass ionomer cements. The cements' working time (WT), setting time (ST), fluoride release, radiopacity, compressive strength (CS), and elastic modulus (EM) were evaluated. Mean differences in CS were analyzed using multivariate ANOVA with Tukey’s post hoc test at p = 0.05.
Results
The WT and ST for both groups ranged from 1.5 to 2.5 min. LG99 series cements showed significantly higher CS (∼65 MPa) and EM (∼2 GPa) than LG117 series (p < 0.05). Both series showed similar fluoride release profiles, peaking at 1.2 mmol/L at 28 days. Radiopacity for LG99 ranged from 0.97 to 1.34, while LG117 ranged from 0.60 to 0.95. Solid state 27Al magic-angle spinning-nuclear magnetic resonance (MAS NMR) confirmed the presence of Al(IV) and Al(VI), indicating setting completion by one day for both series. Bottle glass showed a chemical shift at 55.8 ppm, overlapping with LG99′s Al(IV) signal. The 19F MAS NMR spectra revealed Al-F and F-Sr(n) species in all glasses, with LG117 forming CaF2 after one day in deionized water.
Conclusion
Mixtures of highly reactive ionomer glass and bottle glass produced cements with satisfactory properties for dental applications. Further research is needed to optimize their formulation and properties.
{"title":"Evaluation of dental cements derived from mixtures of highly reactive ionomer glasses and bottle glass: Cement manipulation, mechanical, fluoride ion releasing, radiopaque and setting properties","authors":"Olivia Awino Osiro , Melissa Tiskaya , Saroash Shahid , Robert Graham Hill","doi":"10.1016/j.dental.2024.09.013","DOIUrl":"10.1016/j.dental.2024.09.013","url":null,"abstract":"<div><h3>Objectives</h3><div>To evaluate the mechanical properties, fluoride release, radiopacity, and setting characteristics of dental cements derived from highly reactive ionomer glasses and bottle glass mixtures.</div></div><div><h3>Methods</h3><div>Two highly reactive glass series, LG99 and LG117, were synthesized, milled, sieved, and characterized using XRD and laser particle size analysis. These glasses were mixed with predetermined ratios of ground bottle glass, poly(acrylic acid), and aqueous tartaric acid to form glass ionomer cements. The cements' working time (WT), setting time (ST), fluoride release, radiopacity, compressive strength (CS), and elastic modulus (EM) were evaluated. Mean differences in CS were analyzed using multivariate ANOVA with Tukey’s post hoc test at p = 0.05.</div></div><div><h3>Results</h3><div>The WT and ST for both groups ranged from 1.5 to 2.5 min. LG99 series cements showed significantly higher CS (∼65 MPa) and EM (∼2 GPa) than LG117 series (p < 0.05). Both series showed similar fluoride release profiles, peaking at 1.2 mmol/L at 28 days. Radiopacity for LG99 ranged from 0.97 to 1.34, while LG117 ranged from 0.60 to 0.95. Solid state <sup>27</sup>Al magic-angle spinning-nuclear magnetic resonance (MAS NMR) confirmed the presence of Al(IV) and Al(VI), indicating setting completion by one day for both series. Bottle glass showed a chemical shift at 55.8 ppm, overlapping with LG99′s Al(IV) signal. The <sup>19</sup>F MAS NMR spectra revealed Al-F and F-Sr(n) species in all glasses, with LG117 forming CaF<sub>2</sub> after one day in deionized water.</div></div><div><h3>Conclusion</h3><div>Mixtures of highly reactive ionomer glass and bottle glass produced cements with satisfactory properties for dental applications. Further research is needed to optimize their formulation and properties.</div></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 11","pages":"Pages 1981-1990"},"PeriodicalIF":4.6,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142338149","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}
Pub Date : 2024-11-01DOI: 10.1016/j.dental.2024.09.008
R.J. Wierichs , E.J. Kramer , B. Reiss , A. Roccuzzo , C. Raabe , B. Yilmaz , S. Abou-Ayash
Objectives
The aim of this prospective, multi-center, practice-based cohort study was to analyze factors associated with the success of implant supported all-ceramic single-unit crowns, made by computer-aided-design/computer-aided-manufacturing (CAD-CAM).
Methods
All-ceramic crowns placed in a private practice-based research network (Ceramic Success Analysis, AG Keramik) were analyzed. Data from 567patients with CAD-CAM implant supported all-ceramic crowns placed between 2008–2023 by 54dentists were evaluated. Firstly, all crowns with at least one follow-up control were included (n = 907). Secondly, all crowns being followed up for ≥ 5years and all failures were included (n = 151). At the latest follow-up visit, crowns were considered as successful (not failed) if they were still in function without the need for additional therapy. Multi-level Cox proportional hazards models were used to evaluate the association between a range of predictors and time of success.
Results
Within a mean follow-up period (SD) of 2.5 (2)years (first scenario) and 6.2 (1.2)years (second scenario) [maximum:12years], 27crowns failed (annual failure rate [AFR]:0.74 %). The main failure types were decementation, (n = 11), fracture of the ceramic (n = 4) or Ti-Base (n = 4). In 5-year-scenario, crowns fabricated in the laboratory had 26times lower failure rate than those fabricated chairside (95 %CI:0.0–0.7;p = 0.038). Furthermore, the use of a silane (HR:0.051;95 %CI:0.0–0.5;p = 0.014) and etching of the ceramic (HR:0.053;95 %CI:0.0–0.8;p = 0.035) resulted in a significantly higher risk for failure than their non-use.
Significance
For CAD-CAM manufactured implant supported all-ceramic crowns, high success rates were found in up to 12-year evaluation. Furthermore, after 5years, no patient-or implant-level factors, but operative-level factor (i.e.fabrication method, use of silane/etching) were significantly associated with failure.
The study was registered in the German Clinical Trials Register (DRKS-ID: DRKS00020271).
{"title":"Longevity and risk factors of CAD-CAM manufactured implant-supported all-ceramic crowns - A prospective, multi-center, practice-based cohort study","authors":"R.J. Wierichs , E.J. Kramer , B. Reiss , A. Roccuzzo , C. Raabe , B. Yilmaz , S. Abou-Ayash","doi":"10.1016/j.dental.2024.09.008","DOIUrl":"10.1016/j.dental.2024.09.008","url":null,"abstract":"<div><h3>Objectives</h3><div>The aim of this prospective, multi-center, practice-based cohort study was to analyze factors associated with the success of implant supported all-ceramic single-unit crowns, made by computer-aided-design/computer-aided-manufacturing (CAD-CAM).</div></div><div><h3>Methods</h3><div>All-ceramic crowns placed in a private practice-based research network (Ceramic Success Analysis, AG Keramik) were analyzed. Data from 567patients with CAD-CAM implant supported all-ceramic crowns placed between 2008–2023 by 54dentists were evaluated. Firstly, all crowns with at least one follow-up control were included (n = 907). Secondly, all crowns being followed up for ≥ 5years and all failures were included (n = 151). At the latest follow-up visit, crowns were considered as successful (not failed) if they were still in function without the need for additional therapy. Multi-level Cox proportional hazards models were used to evaluate the association between a range of predictors and time of success.</div></div><div><h3>Results</h3><div>Within a mean follow-up period (SD) of 2.5 (2)years (first scenario) and 6.2 (1.2)years (second scenario) [maximum:12years], 27crowns failed (annual failure rate [AFR]:0.74 %). The main failure types were decementation, (n = 11), fracture of the ceramic (n = 4) or Ti-Base (n = 4). In 5-year-scenario, crowns fabricated in the laboratory had 26times lower failure rate than those fabricated chairside (95 %CI:0.0–0.7;p = 0.038). Furthermore, the use of a silane (HR:0.051;95 %CI:0.0–0.5;p = 0.014) and etching of the ceramic (HR:0.053;95 %CI:0.0–0.8;p = 0.035) resulted in a significantly higher risk for failure than their non-use.</div></div><div><h3>Significance</h3><div>For CAD-CAM manufactured implant supported all-ceramic crowns, high success rates were found in up to 12-year evaluation. Furthermore, after 5years, no patient-or implant-level factors, but operative-level factor (i.e.fabrication method, use of silane/etching) were significantly associated with failure.</div><div>The study was registered in the German Clinical Trials Register (DRKS-ID: DRKS00020271).</div></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 11","pages":"Pages 1962-1969"},"PeriodicalIF":4.6,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142338151","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}
Pub Date : 2024-11-01DOI: 10.1016/j.dental.2024.09.012
Han Sol Kim , Minkyoung Kim , Youngjoon Kim , Hyun Ho Shin , Sang-woo Lee , Ji Hyun Ryu
Objectives
Oral biofilms, including pathogens such as Porphyromonas gingivalis, are involved in the initiation and progression of various periodontal diseases. However, the treatment of these diseases is hindered by the limited efficacy of many antimicrobial materials in removing biofilms under the harsh conditions of the oral cavity. Our objective is to develop a gel-type antimicrobial agent with optimal physicochemical properties, strong tissue adhesion, prolonged antimicrobial activity, and biocompatibility to serve as an adjunctive treatment for periodontal diseases.
Methods
Phenylboronic acid-conjugated alginate (Alg–PBA) was synthesized using a carbodiimide coupling agent. Alg–PBA was then combined with tannic acid (TA) to create an Alg–PBA/TA hydrogel. The composition of the hydrogel was optimized to enhance its mechanical strength and tissue adhesiveness. Additionally, the hydrogel’s self-healing ability, erosion and release profile, biocompatibility, and antimicrobial activity against P. gingivalis were thoroughly characterized.
Results
The Alg–PBA/TA hydrogels, with a final concentration of 5 wt% TA, exhibited both mechanical properties comparable to conventional Minocycline gel and strong tissue adhesiveness. In contrast, the Minocycline gel demonstrated negligible tissue adhesion. The Alg–PBA/TA hydrogel also retained its rheological properties under repeated 5 kPa stress owing to its self-healing capability, whereas the Minocycline gel showed irreversible changes in rheology after just one stress cycle. Additionally, Alg–PBA/TA hydrogels displayed a sustained erosion and TA release profile with minimal impact on the surrounding pH. Additionally, the hydrogels exhibited potent antimicrobial activity against P. gingivalis, effectively eliminating its biofilm without compromising the viability of MG-63 cells.
Significance
The Alg–PBA/TA hydrogel demonstrates an optimal combination of mechanical strength, self-healing ability, tissue adhesiveness, excellent biocompatibility, and sustained antimicrobial activity against P. gingivalis. These attributes make it superior to conventional Minocycline gel. Thus, the Alg–PBA/TA hydrogel is a promising antiseptic candidate for adjunctive treatment of various periodontal diseases.
{"title":"Antimicrobial adhesive self-healing hydrogels for efficient dental biofilm removal from periodontal tissue","authors":"Han Sol Kim , Minkyoung Kim , Youngjoon Kim , Hyun Ho Shin , Sang-woo Lee , Ji Hyun Ryu","doi":"10.1016/j.dental.2024.09.012","DOIUrl":"10.1016/j.dental.2024.09.012","url":null,"abstract":"<div><h3>Objectives</h3><div>Oral biofilms, including pathogens such as <em>Porphyromonas gingivalis</em>, are involved in the initiation and progression of various periodontal diseases. However, the treatment of these diseases is hindered by the limited efficacy of many antimicrobial materials in removing biofilms under the harsh conditions of the oral cavity. Our objective is to develop a gel-type antimicrobial agent with optimal physicochemical properties, strong tissue adhesion, prolonged antimicrobial activity, and biocompatibility to serve as an adjunctive treatment for periodontal diseases.</div></div><div><h3>Methods</h3><div>Phenylboronic acid-conjugated alginate (Alg–PBA) was synthesized using a carbodiimide coupling agent. Alg–PBA was then combined with tannic acid (TA) to create an Alg–PBA/TA hydrogel. The composition of the hydrogel was optimized to enhance its mechanical strength and tissue adhesiveness. Additionally, the hydrogel’s self-healing ability, erosion and release profile, biocompatibility, and antimicrobial activity against <em>P. gingivalis</em> were thoroughly characterized.</div></div><div><h3>Results</h3><div>The Alg–PBA/TA hydrogels, with a final concentration of 5 wt% TA, exhibited both mechanical properties comparable to conventional Minocycline gel and strong tissue adhesiveness. In contrast, the Minocycline gel demonstrated negligible tissue adhesion. The Alg–PBA/TA hydrogel also retained its rheological properties under repeated 5 kPa stress owing to its self-healing capability, whereas the Minocycline gel showed irreversible changes in rheology after just one stress cycle. Additionally, Alg–PBA/TA hydrogels displayed a sustained erosion and TA release profile with minimal impact on the surrounding pH. Additionally, the hydrogels exhibited potent antimicrobial activity against <em>P. gingivalis</em>, effectively eliminating its biofilm without compromising the viability of MG-63 cells.</div></div><div><h3>Significance</h3><div>The Alg–PBA/TA hydrogel demonstrates an optimal combination of mechanical strength, self-healing ability, tissue adhesiveness, excellent biocompatibility, and sustained antimicrobial activity against <em>P. gingivalis</em>. These attributes make it superior to conventional Minocycline gel. Thus, the Alg–PBA/TA hydrogel is a promising antiseptic candidate for adjunctive treatment of various periodontal diseases.</div></div>","PeriodicalId":298,"journal":{"name":"Dental Materials","volume":"40 11","pages":"Pages 1970-1980"},"PeriodicalIF":4.6,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142338146","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}
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