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Bond durability and surface states of titanium, Ti-6Al-4V alloy, and zirconia for implant materials.Journal of Prosthodontic Research Apr 2022Screw-retained implant crowns used as dental implants comprise a zirconia coping and titanium base bonded using resin cement. These devices are prone to debonding...
PURPOSE
Screw-retained implant crowns used as dental implants comprise a zirconia coping and titanium base bonded using resin cement. These devices are prone to debonding failures. This study investigated the bond characteristics of implant materials based on shear bond strength (SBS) and surface characteristics.
METHODS
Chemically pure (CP) titanium grade-4 (Ti), Ti-6Al-4V alloy (Ti-6Al-4V), and tetragonal polycrystalline zirconia (zirconia) were evaluated as adherent materials. Plates of each material were polished, primed for the respective resin cements, and cemented using either methyl methacrylate-based resin cement (Super-Bond) or composite-based resin cement (Panavia). The cemented samples were subjected to 10,000 thermocycles alternating between 5 and 55 °C, and the SBS were obtained before and after thermocycling. The sample surfaces were characterized based on surface observations, roughness, and free energy (SFE).
RESULTS
The SBSs of all materials bonded using Panavia were significantly compromised during thermocycling and reached zero. Although the SBSs of Ti and Ti-6Al-4V bonded using Super-Bond were not significantly affected by thermocycling, those of zirconia decreased significantly. The bond durability between zirconia and Super-Bond was improved via alumina air-abrasion, which caused no significant loss of SBS after thermocycling. Surface analyses of the air-abraded zirconia validated these results and confirmed that its surface roughness and SFE were significantly increased.
CONCLUSION
The bond durability between resin cement and zirconia was lower than that between Ti and Ti-6Al-4V. The alumina air-abrasion pretreatment of zirconia improved the SFE and surface roughness, thereby enhancing bond durability.
Topics: Alloys; Aluminum Oxide; Dental Bonding; Dental Materials; Materials Testing; Resin Cements; Shear Strength; Surface Properties; Titanium; Zirconium
PubMed: 34470984
DOI: 10.2186/jpr.JPR_D_20_00297 -
Journal of Prosthodontic Research Jun 2021A bioactive high performance polymer (BioHPP) and computer-aided design/computer-aided manufacturing (CAD/CAM) composite resin materials are a relatively new class of... (Review)
Review
PURPOSE
A bioactive high performance polymer (BioHPP) and computer-aided design/computer-aided manufacturing (CAD/CAM) composite resin materials are a relatively new class of dental biomaterials, that are biocompatible and have good aesthetic features. In this review paper, we will summarize literature and publication data on the characteristics of the mentioned materials, as well as their potential application in the dental prosthetics.
STUDY SELECTION
Available studies and literature reviews from PubMed, SCIndex, Scopus and Google Scholar corresponding to polyetheretherketone (PEEK), high-performance polymers, reinforced composite materials, composite materials, resins, glass-fiber reinforced materials, CAD/CAM materials, dental implants, removable and fixed dental were reviewed.
RESULTS
To avoid many disadvantages of metals and their alloys in dental practice, such as inadequate color, high density, thermal conductivity and possible allergic reactions, materials based on polymers (such as BioHPP), and CAD/CAM composite resins are being developed. These materials have significantly better aesthetics and physical-mechanical properties. They are biocompatible materials that are lightweight, resistant, durable, exhibit high bending and compression resistance.
CONCLUSIONS
The use of CAD/CAM composite resin materials and BioHPP in dentistry has begun recently, so the data about their potential clinical use are limited. Most of their features have been demonstrated through laboratory testing, while clinical studies are relatively scarce, so the need for further clinical trials is emphasized.
Topics: Ceramics; Composite Resins; Computer-Aided Design; Dental Materials; Materials Testing; Polymers; Prosthodontics; Surface Properties
PubMed: 32981910
DOI: 10.2186/jpr.JPOR_2019_404 -
Acta Biomaterialia Sep 2023The preservation of oral health over a person's lifespan is a key factor for a high quality of life. Sustaining oral health requires high-end dental materials with a...
The preservation of oral health over a person's lifespan is a key factor for a high quality of life. Sustaining oral health requires high-end dental materials with a plethora of attributes such as durability, non-toxicity and ease of application. The combination of different requirements leads to increasing miniaturization and complexity of the material components such as the composite and adhesives, which makes the precise characterization of the material blend challenging. Here, we demonstrate how modern IR spectroscopy and imaging from the micro- to the nanoscale can provide insights on the chemical composition of the different material sections of a dental filling. We show how the recorded IR-images can be used for a fast and non-destructive porosity determination of the studied adhesive. Furthermore, the nanoscale study allows precise assessment of glass cluster structures and distribution within their characteristic organically modified ceramic (ORMOCER) matrix and an assessment of the interface between the composite and adhesive material. For the study we used a Fourier-Transform-IR (FTIR) microscope and a quantum cascade laser-based IR-microscope (QCL-IR) for the microscale analysis and a scattering-type scanning near-field optical microscopy (s-SNOM) for the nanoscale analysis. The paper ends with an in-depth discussion of the strengths and weaknesses of the different imaging methods to give the reader a clear picture for which scientific question the microscopes are best suited for. STATEMENT OF SIGNIFICANCE: Modern resin-based composites for dental restoration are complex multi-compound materials. In order to improve these high-end materials, it is important to investigate the molecular composition and morphology of the different parts. An emergent method to characterize these materials is infrared spectroscopic imaging, which combines the strength of infrared spectroscopy and an imaging approach known from optical microscopy. In this work, three state of the art methods are compared for investigating a dental filling including FTIR- and quantum cascade laser IR-imaging microscopy for the microscale and scattering-type scanning near-field optical microscopy for the nanoscale.
Topics: Humans; Spectroscopy, Fourier Transform Infrared; Quality of Life; Microscopy; Spectrophotometry, Infrared; Dental Materials; Materials Testing; Composite Resins
PubMed: 37479158
DOI: 10.1016/j.actbio.2023.07.017 -
Clinical Oral Investigations Oct 2022Resin-based materials are applied in every branch of dentistry. Due to their tendency to release substances in the oral environment, doubts have been raised about their... (Review)
Review
OBJECTIVES
Resin-based materials are applied in every branch of dentistry. Due to their tendency to release substances in the oral environment, doubts have been raised about their actual safety. This review aims to provide a comprehensive analysis of the last decade literature regarding the concentrations of elutable substances released from dental resin-based materials in different type of solvents.
MATERIALS AND METHODS
All the literature published on dental journals between January 2010 and April 2022 was searched using international databases (PubMed, Scopus, Web of Science). Due to strict inclusion criteria, only 23 papers out of 877 were considered eligible. The concentration of eluted substances related to surface and volume of the sample was analyzed, considering data at 24 h as a reference. The total cumulative release was examined as well.
RESULTS
The most eluted substances were HEMA, TEGDMA, and BPA, while the less eluted were Bis-GMA and UDMA. Organic solvents caused significantly higher release of substances than water-based ones. A statistically significant inverse correlation between the release of molecules and their molecular mass was observed. A statistically significant positive correlation between the amount of released molecule and the specimen surface area was detected, as well as a weak positive correlation between the release and the specimen volume.
CONCLUSIONS
Type of solvent, molecular mass of eluates, and specimen surface and volume affect substances release from materials.
CLINICAL RELEVANCE
It could be advisable to rely on materials based on monomers with a reduced elution tendency for clinical procedures.
Topics: Bisphenol A-Glycidyl Methacrylate; Composite Resins; Dental Materials; Materials Testing; Methacrylates; Polyethylene Glycols; Polymethacrylic Acids; Solvents; Water
PubMed: 35870020
DOI: 10.1007/s00784-022-04625-4 -
Dental Materials Journal Nov 2022The present study examined color changes in the tooth-colored restorative materials, zirconia (3Y-TZP), resin composite, and porcelain. The colors (CIELab) of these...
The present study examined color changes in the tooth-colored restorative materials, zirconia (3Y-TZP), resin composite, and porcelain. The colors (CIELab) of these materials were measured using a spectrophotometer. Specimens were immersed in black tea or curry for 1 and 7 days, after which colors were re-assessed. Color differences (∆Eab) before and after immersion were calculated. Specimens after the 7-day immersion were ultrasonically cleaned, and colors were measured again to assess the color recovery rate. The surface free energy, roughness, and water sorption/solubility of each material were also evaluated. Specimens were observed under a scanning electron microscope. The ∆Eab of 3Y-TZP was the smallest with both immersions. Resin composite had the smallest recovery rate. The surface free energy and roughness of 3Y-TZP were smaller than those of porcelain. 3Y-TZP and porcelain showed almost no sorption during the 7-day period. The present results revealed that 3Y-TZP exhibited the strongest resistance to discoloration.
Topics: Dental Porcelain; Water; Materials Testing; Surface Properties; Zirconium; Dental Materials; Composite Resins; Beverages; Lipids; Color
PubMed: 35793942
DOI: 10.4012/dmj.2022-021 -
Influence of yttria content and surface treatment on the strength of translucent zirconia materials.The Journal of Prosthetic Dentistry Apr 2023Newly developed translucent zirconia materials have been used for anterior monolithic complete coverage restorations. Surface treatments can improve adhesion, as well as...
STATEMENT OF PROBLEM
Newly developed translucent zirconia materials have been used for anterior monolithic complete coverage restorations. Surface treatments can improve adhesion, as well as decrease or increase the strength of ceramics. However, information on the influence of surface treatments on the strength of translucent zirconias is sparse.
PURPOSE
The purpose of this in vitro study was to measure and characterize the effects of different surface treatments, including airborne-particle abrasion, on the strength of different translucent 4 mol% and 5 mol% yttria-stabilized zirconia materials.
MATERIALS AND METHODS
Disks (N=160) made from 4 types of translucent yttria-stabilized zirconia materials were surface-treated in 4 ways: Control groups were hand-polished with 2000-grit silicon carbide abrasive paper; as-machined; glass bead airborne-particle abraded; and alumina airborne-particle abraded. The biaxial flexural strength was measured by using a piston-on-3-ball test in a universal testing machine. The simple main effects of material type and surface treatment and their interaction on biaxial flexural strength were evaluated with 2-way ANOVA (α=.05). A priori, 1-way ANOVA and the Tukey multiple comparisons tests were used within material and treatment types (α=.05). Surface morphology was assessed by using scanning electron microscopy. Translucency, absolute transmittance, was measured by using a spectrophotometer.
RESULTS
Two-way ANOVA revealed that the effects of zirconia type, surface treatment, and their interaction all significantly affected biaxial flexural strength (P<.001). One-way ANOVA revealed that the 4Y material was stronger than all 5Y materials, regardless of surface treatment; all 5Y materials were ranked from strongest to weakest as polished; as-machined, or glass bead abraded; and alumina abraded. The 4Y material was stronger when alumina abraded than when glass bead abraded. Scanning electron microscopy showed that as-polished surfaces were smoother than all others; as-machined and glass bead abraded surfaces displayed little difference; alumina abraded was the roughest; and differences among materials were not discerned. The 1-way ANOVA and multiple comparisons testing showed that the 4Y material had less absolute transmittance, approximately 5% less, than all the 5Y materials.
CONCLUSIONS
Zirconia material type and surface treatment influenced the strength of translucent zirconia materials; a 4 mol% zirconia material was stronger than 5 mol% zirconia materials for all surface treatments tested; airborne-particle abrasion using alumina had a slight strengthening effect on a 4 mol% zirconia but had a weakening effect on 5 mol% materials; airborne-particle abrasion by using alumina produced the roughest surfaces on all materials; and the 4 mol% material was slightly less translucent than the 5 mol% materials.
Topics: Dental Materials; Materials Testing; Surface Properties; Aluminum Oxide
PubMed: 34452741
DOI: 10.1016/j.prosdent.2021.07.001 -
Dental Materials : Official Publication... Sep 2022This study aimed to investigate human osteoblasts (HOB) response towards different dental implant abutment materials.
OBJECTIVES
This study aimed to investigate human osteoblasts (HOB) response towards different dental implant abutment materials.
METHODS
Five dental implant abutment materials were investigated: (1) titanium (Ti), (2) titanium coated nitride (TiN), (3) cobalt chromium (CoCr), (4) zirconia (ZrO₂), and (5) modified polyether ether ketone (m-PEEK). HOBs were cultured, expanded, and seeded according to the supplier's protocol (PromoCell, UK). Cell proliferation and cytotoxicity were evaluated at days 1, 3, 5, and 10 using Alamar Blue (alamarBlue) and lactate dehydrogenase (LDH) colorimetric assays. Data were analysed via two-way ANOVA, one-way ANOVA and Tukey's post hoc test (significance was determined as p < 0.05 for all tests).
RESULTS
All the investigated materials showed high and comparable initial proliferation activities apart from ZrO₂ (46.92%), with P% of 79.91%, 68.77%, 73.20%, and 65.46% for Ti, TiN, CoCr, and m-PEEK, respectively. At day 10, all materials exhibited comparable and lower P% than day 1 apart from TiN (70.90%) with P% of 30.22%, 40.64%, 37.27%, and 50.65% for Ti, CoCr, ZrO₂, and m-PEEK, respectively. The cytotoxic effect of the investigated materials was generally low throughout the whole experiment. At day 10, the cytotoxicity % was 7.63%, 0.21%, 13.30%, 5.32%, 8.60% for Ti, TiN, CoCr, ZrO₂, and m-PEEK. The Two-way ANOVA and Tukey's Multiple Comparison Method highlighted significant material and time effects on cell proliferation and cytotoxicity, and a significant interaction (p < 0.0001) between the tested materials. Notably, TiN and m-PEEK showed improved HOB proliferation activity and cytotoxic levels than the other investigated materials. In addition, a non-significant negative correlation between viability and cytotoxicity was found for all tested materials. Ti (p = 0.07), TiN (p = 0.28), CoCr (p = 0.15), ZrO₂ (p = 0.17), and m-PEEK (p = 0.12).
SIGNIFICANCE
All the investigated materials showed excellent biocompatibility properties with more promising results for the newly introduced TiN and m-PEEK as alternatives to the traditionally used dental implant and abutment materials.
Topics: Humans; Dental Abutments; Dental Implants; Dental Materials; Ketones; Materials Testing; Osteoblasts; Polyethylene Glycols; Titanium; Zirconium
PubMed: 35909000
DOI: 10.1016/j.dental.2022.07.005 -
Dental Materials : Official Publication... Jun 2022This study was designed to investigate CAD/CAM restorative blocks and other resin-based materials by (i) determining their chemical composition, (ii) comparing their...
OBJECTIVES
This study was designed to investigate CAD/CAM restorative blocks and other resin-based materials by (i) determining their chemical composition, (ii) comparing their radiopacity and (iii) correlating their radiopacity with specimen thickness.
METHODS
Disk specimens, of 1and 2 mm thickness (n = 3), were prepared from five CAD/CAM and six resin-based composites (RBCs). The CAD/CAM resin-composites included aesthetic types: CeraSmart (CS), Grandio Blocs (GB), Lava Ultimate (LU), plus a polymer infiltrated ceramic Vita Enamic (VE), and a feldspathic ceramic Vita Mark II (VM II). The six RBCs were for different clinical applications: direct filling, flowable, bulk fill, base and two luting cements. The specimens were radiographed alongside an aluminium step wedge and a tooth section. Digital images were analysed, and the radiopacity of each specimen was determined according to ISO 1311/2014. Statistical analyses of radiopacity, expressed as mm Al (n = 15), were carried out using the Kruskal-Wallis test followed by pairwise comparisons (α = 0.05).
RESULTS
Radiopacities of CAD/CAM materials were, in ascending order, VE, VM II, CS, LU, and GB. At 1 mm thickness, the radiopacities of all CAD/CAM specimens were matching or slightly lower than enamel. At 2-mm thickness, the resin composite blocks were significantly more radiopaque than the ceramics VE and VM II (p < 0.0001). No statistically significant differences in radiopacity were detected between the 1-mm thick infiltrated ceramic, enamel, dentin and various resin composites except for filling and bulk fill types. The radiopacity of polymer-infiltrated ceramics was low despite the presence of radiopacifying elements and high filler content.
SIGNIFICANCE
Identifying thin restorations in standard radiographs is necessary with the development and expanded application of 'digital' dental materials in restorative treatment. This study confirmed the joint influence of composition and thickness on radiopacity. CAD/CAM restorative materials showed thickness-dependant radiopacity. But polymer-infiltrated ceramics were fairly radiolucent. There is a need to revisit radiopacity requirements for CAD/CAM restorative materials.
Topics: Ceramics; Composite Resins; Computer-Aided Design; Dental Materials; Dental Porcelain; Esthetics, Dental; Materials Testing; Surface Properties
PubMed: 35537869
DOI: 10.1016/j.dental.2022.04.025 -
Journal of Prosthodontics : Official... Apr 2023To measure the flexural strength and Weibull characteristics of aged and nonaged printed interim dental material fabricated with different layer thickness. (Comparative Study)
Comparative Study
PURPOSE
To measure the flexural strength and Weibull characteristics of aged and nonaged printed interim dental material fabricated with different layer thickness.
MATERIAL AND METHODS
Bars (25×2×2 mm) were additively fabricated by using a polymer printer (Asiga Max) and an interim resin (Nexdent C&B MFH). Specimens were fabricated with the same printing parameters and postprocessing procedures, but with 7 different layer thickness: 50 (control or 50-G group), 10 (10-G group), 25 (25-G group), 75 (75-G group), 100 (100-G group), 125 (125-G group), and 150 μm (150-G group). Two subgroups were created: nonaged and aged subgroups (n = 10). A universal testing machine was selected to measure flexural strength. Two-parameter Weibull distribution values were computed. Two-way ANOVA and Tukey tests were selected for statistical evaluation of the data (α = 0.05).
RESULTS
Artificial aging methods (p < 0.001) were a significant predictor of the flexural strength computed. Aged specimens acquired less flexural strength than nonaged specimens. The Weibull distribution obtained the highest shape for nonaged 50-G and 75-G group specimens compared with those of other nonaged groups, while the Weibull distribution showed the highest shape for aged 125-G specimens.
CONCLUSIONS
The flexural strength of the additively fabricated interim material examined was not influenced by the layer thickness at which the specimens were fabricated; however, artificial aging techniques reduced its flexural strength. Aged specimens presented lower Weibull distribution values compared with nonaged specimens, except for the 125-G specimens.
Topics: Flexural Strength; Dental Materials; Materials Testing; Surface Properties; Stress, Mechanical; Printing, Three-Dimensional; Polymerization; Polymers
PubMed: 35924435
DOI: 10.1111/jopr.13582 -
Clinical Oral Investigations May 2022To evaluate clinical performance of the new CAD/CAM resin-matrix ceramics and compare it with ceramic partial coverage restorations. (Review)
Review
OBJECTIVE
To evaluate clinical performance of the new CAD/CAM resin-matrix ceramics and compare it with ceramic partial coverage restorations.
MATERIALS AND METHODS
An electronic search of 3 databases (The National Library of Medicine (MEDLINE/PubMed), Scopus, and the Cochrane Central Register of Controlled Trials) was conducted. English clinical studies published between 2005 and September 2020 that evaluated the clinical performance of CAD/CAM resin-matrix ceramics inlays, onlays, or overlays were selected. The primary clinical question was applied according to PICOS strategy (Population, Intervention, Comparison, Outcome, Study design). The included studies were individually evaluated for risk of bias according to the modified Cochrane Collaboration tool criteria.
RESULTS
A total of 7 studies were included according to the established inclusion and exclusion criteria. From the included studies, 6 were randomized clinical trials while one study was longitudinal observational study without control group. According to the results of the included studies, the success rate of CAD/CAM resin-based composite ranged from 85.7 to 100% whereas the success rate reported for ceramic partial coverage restorations ranged from 93.3 to 100%. Fractures and debondings are found to be the most common cause of restorations failure.
CONCLUSION
CAD/CAM resin-based composite can be considered a reliable material for partial coverage restorations with clinical performance similar to glass ceramic restorations. However, this result needs to be confirmed in long-term evaluations.
CLINICAL RELEVANCE
CAD/CAM resin-based composites provide a potential alternative to ceramic indirect restorations. However, clinicians must be aware of the lake of knowledge regarding long-term outcome.
Topics: Ceramics; Composite Resins; Computer-Aided Design; Dental Materials; Dental Porcelain; Inlays; Longitudinal Studies; Observational Studies as Topic
PubMed: 35320383
DOI: 10.1007/s00784-022-04449-2