Radiopacity and mechanical properties of dental adhesives with strontium hydroxyapatite nanofillers

The incorporation of metallic oxides in dental adhesives has been a strategy to confer improved radiopacity and physicochemical properties for polymers. Tailoring the structure of these fillers could contribute to their application in therapeutic strategies for dental restorations. The aim of this study was to evaluate the incorporation of niobic acid into experimental dental adhesives, and compare these adhesives to niobium pentoxide containing adhesives. A control group without Nb2O5·n H2O or Nb2O5 was also used for comparison. Niobium-based particles have been used as a feasible approach, mainly because of their bioactivity. In this study, hydrated niobium pentoxide, also called niobic acid (Nb2O5·n H2O), was incorporated into an experimental dental adhesive as a potential catalyst for monomer conversion. A base resin for dental adhesive was formulated with methacrylate monomers and photoinitiators. Two types of oxides were tested as filler for this adhesive: Nb2O5·n H2O or niobium pentoxide (Nb2O5). Both fillers were added separately into the experimental adhesive at 0, 2.5, 5, and 10 wt.%. One group without Nb2O5·n H2O or Nb2O5 (0 wt.% of filler addition) was used as a control group. The formulated materials were analyzed for radiopacity according to the ISO 4049 and used FTIR analysis to assess the degree of conversion (DC) and the maximum polymerization rate (RPmax). Mechanical properties were analyzed by ultimate tensile strength (UTS) in a testing machine. Softening in solvent was conducted by measuring Knoop microhardness before and after immersion of samples in ethanol. Normality of data was assessed with Shapiro-Wilk, and comparisons between factors were conducted with two-way ANOVA and Tukey at 5% of significance. Both fillers, Nb2O5 or Nb2O5·n H2O, increased the radiopacity of dental adhesives in comparison to the unfilled adhesive (p < 0.05). There were no differences among groups for the ultimate tensile strength (p > 0.05), and all groups containing Nb2O5 or Nb2O5·n H2O improved the resistance against softening in solvent (p < 0.05). The groups with 5 and 10 wt% addition of Nb2O5 showed decreased DC compared to the control group (p < 0.05), while the addition of Nb2O5·nH2O up to 10 wt% did not alter the DC (p > 0.05). The polymerization rate did not change among groups (p > 0.05). In conclusion, Nb2O5·n H2O is a promising filler to be incorporated into dental adhesives providing proper mechanical properties, improved resistance against solvents, and increased radiopacity, without changing the DC.

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Evaluation of degree of conversion, microtensile bond strength and mechanical properties of three etch-and-rinse dental adhesives

Polímeros ◽

10.1590/0104-1428.02316 ◽

2017 ◽

Vol 27 (3) ◽

pp. 230-236 ◽

Cited By ~ 1

Author(s):

Samantha Ariadne Alves de Freitas ◽

Marco Daniel Septimo Lanza ◽

Karina Kato Carneiro ◽

Alessandro Dourado Loguercio ◽

José Bauer

Keyword(s):

Mechanical Properties ◽

Bond Strength ◽

Degree Of Conversion ◽

Microtensile Bond Strength ◽

Dental Adhesives ◽

Etch And Rinse

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Evaluation of the mechanical properties of dental adhesives and glass-ionomer cements

Clinical Oral Investigations ◽

10.1007/s00784-009-0259-3 ◽

2009 ◽

Vol 14 (1) ◽

pp. 79-87 ◽

Cited By ~ 27

Author(s):

Elisa Magni ◽

Marco Ferrari ◽

Reinhard Hickel ◽

Nicoleta Ilie

Keyword(s):

Mechanical Properties ◽

Glass Ionomer Cements ◽

Glass Ionomer ◽

Dental Adhesives

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INFLUENCE OF PRIMER AND ADHESIVE MIXTURE ON THE REAL-TIME POLYMERIZATION AND MECHANICAL PROPERTIES OF EXPERIMENTAL DENTAL ADHESIVES

Brazilian Journal of Development ◽

10.34117/bjdv6n8-423 ◽

2020 ◽

Vol 6 (8) ◽

pp. 60013-60023

Author(s):

Maria Malerba Colombi Humel ◽

Lucia Trazzi Prieto ◽

Josué Junior Araujo Pierote ◽

Cintia Tereza Pimenta de Araujo ◽

João Victor Frazão Câmara ◽

...

Keyword(s):

Mechanical Properties ◽

Real Time ◽

Dental Adhesives ◽

The Real

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Phase Transformations in Ti-7w/oMo-3w/oMe Alloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052584 ◽

1974 ◽

Vol 32 ◽

pp. 514-515

Author(s):

S. Fujishiro

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Transmission Electron Microscopy ◽

Tensile Strength ◽

Mechanical Processing ◽

Ray Method ◽

X Ray ◽

Transmission Electron ◽

Water Quench ◽

Alpha Beta

The mechanical properties of three titanium alloys (Ti-7Mo-3Al, Ti-7Mo- 3Cu and Ti-7Mo-3Ta) were evaluated as function of: 1) Solutionizing in the beta field and aging, 2) Thermal Mechanical Processing in the beta field and aging, 3) Solutionizing in the alpha + beta field and aging. The samples were isothermally aged in the temperature range 300° to 700*C for 4 to 24 hours, followed by a water quench. Transmission electron microscopy and X-ray method were used to identify the phase formed. All three alloys solutionized at 1050°C (beta field) transformed to martensitic alpha (alpha prime) upon being water quenched. Despite this heavily strained alpha prime, which is characterized by microtwins the tensile strength of the as-quenched alloys is relatively low and the elongation is as high as 30%.

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Effects of cooling rate on the mechanical properties of dual phase treated vanadium steels

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074896 ◽

1983 ◽

Vol 41 ◽

pp. 220-221

Author(s):

L.J. Chen ◽

H.C. Cheng ◽

J.R. Gong ◽

J.G. Yang

Keyword(s):

Mechanical Properties ◽

Cooling Rate ◽

Automobile Industry ◽

High Strength ◽

Weight Percent ◽

Low Alloy Steels ◽

Dual Phase ◽

Resource Requirement ◽

Alloy Steels ◽

Potential Weight

For fuel savings as well as energy and resource requirement, high strength low alloy steels (HSLA) are of particular interest to automobile industry because of the potential weight reduction which can be achieved by using thinner section of these steels to carry the same load and thus to improve the fuel mileage. Dual phase treatment has been utilized to obtain superior strength and ductility combinations compared to the HSLA of identical composition. Recently, cooling rate following heat treatment was found to be important to the tensile properties of the dual phase steels. In this paper, we report the results of the investigation of cooling rate on the microstructures and mechanical properties of several vanadium HSLA steels.The steels with composition (in weight percent) listed below were supplied by China Steel Corporation: 1. low V steel (0.11C, 0.65Si, 1.63Mn, 0.015P, 0.008S, 0.084Aℓ, 0.004V), 2. 0.059V steel (0.13C, 0.62S1, 1.59Mn, 0.012P, 0.008S, 0.065Aℓ, 0.059V), 3. 0.10V steel (0.11C, 0.58Si, 1.58Mn, 0.017P, 0.008S, 0.068Aℓ, 0.10V).

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Lattice Imaging of Grain Boundaries in Ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100078171 ◽

1977 ◽

Vol 35 ◽

pp. 114-115

Author(s):

D. R. Clarke ◽

G. Thomas

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Silicon Nitride ◽

Grain Boundaries ◽

High Temperature Strength ◽

Current Interest ◽

Lattice Imaging ◽

Special Significance ◽

Structural Applications ◽

Refractory Ceramics

Grain boundaries have long held a special significance to ceramicists. In part, this has been because it has been impossible until now to actually observe the boundaries themselves. Just as important, however, is the fact that the grain boundaries and their environs have a determing influence on both the mechanisms by which powder compaction occurs during fabrication, and on the overall mechanical properties of the material. One area where the grain boundary plays a particularly important role is in the high temperature strength of hot-pressed ceramics. This is a subject of current interest as extensive efforts are being made to develop ceramics, such as silicon nitride alloys, for high temperature structural applications. In this presentation we describe how the techniques of lattice fringe imaging have made it possible to study the grain boundaries in a number of refractory ceramics, and illustrate some of the findings.

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Electron Microscopic Observation of the Longitudinal Organization of Poly (p-Phenylene Terephthalamide) Fibers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055734 ◽

1982 ◽

Vol 40 ◽

pp. 680-681

Author(s):

Li Li-Sheng ◽

L.F. Allard ◽

W.C. Bigelow

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Microscopic Observation ◽

Electron Microscopic Observation ◽

Electron Microscopic ◽

Aromatic Polyamides ◽

Radial Arrangement ◽

Scanning Electron ◽

Better Than

The aromatic polyamides form a class of fibers having mechanical properties which are much better than those of aliphatic polyamides. Currently, the accepted morphology of these fibers as proposed by M.G. Dobb, et al. is a radial arrangement of pleated sheets, with the plane of the pleats parallel to the axis of the fiber. We have recently obtained evidence which supports a different morphology of this type of fiber, using ultramicrotomy and ion-thinning techniques to prepare specimens for transmission and scanning electron microscopy.

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