Enamel Remineralization with Novel Bioactive Glass Air Abrasion

Enamel demineralization or white spot lesions (WSLs) are a frequent complication associated with fixed appliance–based orthodontic treatment. The remineralization potential of a novel fluoride-containing bioactive glass (QMAT3) propelled via an air abrasion system was compared with Sylc glass and artificial saliva on artificially induced WSLs. Thirty extracted human premolars were randomly assigned into 3 groups ( n = 10) per method of treatment and scanned with optical coherence tomography and noncontact profilometer in the 4 enamel states: sound, demineralized, after glass propulsion, and after immersion in artificial saliva. Knoop hardness testing was also performed. Twenty additional prepared teeth samples were also randomly selected for examination by scanning electron microscopy and energy-dispersive X-ray spectroscopy (2 teeth per technique) under each of the 4 enamel conditions. 19F MAS-NMR (magic angle spinning–nuclear magnetic resonance) was also used to detect the type of apatite formed on the enamel surface. Significant enamel remineralization with surface roughness and intensity of light backscattering similar to that of sound enamel was observed following treatment with QMAT3. In addition, mineral deposits were detected on the remineralized enamel surfaces, forming a protective layer and improving its hardness. This layer was rich in calcium, phosphate, and fluoride; 19F MAS-NMR confirmed the formation of fluorapatite. This finding is particularly beneficial since fluorapatite is more chemically stable than hydroxyapatite and has greater resistance to acid attack. Hence, a promising fluoride-containing bioactive glass for enamel remineralization has been developed, although further clinical evaluation and refinement is required.

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Combination of solid state NMR and DFT calculation to elucidate the state of sodium in hard carbon electrodes

Journal of Materials Chemistry A ◽

10.1039/c6ta04273b ◽

2016 ◽

Vol 4 (34) ◽

pp. 13183-13193 ◽

Cited By ~ 31

Author(s):

Ryohei Morita ◽

Kazuma Gotoh ◽

Mika Fukunishi ◽

Kei Kubota ◽

Shinichi Komaba ◽

...

Keyword(s):

Solid State ◽

Solid State Nmr ◽

Dft Calculation ◽

Magic Angle Spinning ◽

The State ◽

Mas Nmr ◽

Magic Angle ◽

Multiple Quantum ◽

Hard Carbon ◽

Angle Spinning

We examined the state of sodium electrochemically inserted in HC prepared at 700–2000 °C using solid state Na magic angle spinning (MAS) NMR and multiple quantum (MQ) MAS NMR.

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Sampling Method Affects HR-MAS NMR Spectra of Healthy Caprine Brain Biopsies

Metabolites ◽

10.3390/metabo11010038 ◽

2021 ◽

Vol 11 (1) ◽

pp. 38

Author(s):

Annakatrin Häni ◽

Gaëlle Diserens ◽

Anna Oevermann ◽

Peter Vermathen ◽

Christina Precht

Keyword(s):

Nmr Spectroscopy ◽

Sampling Method ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Magic Angle ◽

1H Nuclear Magnetic Resonance ◽

Rapid Changes ◽

Tissue Degradation ◽

Angle Spinning

The metabolic profiling of tissue biopsies using high-resolution–magic angle spinning (HR-MAS) 1H nuclear magnetic resonance (NMR) spectroscopy may be influenced by experimental factors such as the sampling method. Therefore, we compared the effects of two different sampling methods on the metabolome of brain tissue obtained from the brainstem and thalamus of healthy goats by 1H HR-MAS NMR spectroscopy—in vivo-harvested biopsy by a minimally invasive stereotactic approach compared with postmortem-harvested sample by dissection with a scalpel. Lactate and creatine were elevated, and choline-containing compounds were altered in the postmortem compared to the in vivo-harvested samples, demonstrating rapid changes most likely due to sample ischemia. In addition, in the brainstem samples acetate and inositols, and in the thalamus samples ƴ-aminobutyric acid, were relatively increased postmortem, demonstrating regional differences in tissue degradation. In conclusion, in vivo-harvested brain biopsies show different metabolic alterations compared to postmortem-harvested samples, reflecting less tissue degradation. Sampling method and brain region should be taken into account in the analysis of metabolic profiles. To be as close as possible to the actual situation in the living individual, it is desirable to use brain samples obtained by stereotactic biopsy whenever possible.

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MAS-NMR of [Pyr13][Tf2N] and [Pyr16][Tf2N] Ionic Liquids Confined to Carbon Black: Insights and Pitfalls

Molecules ◽

10.3390/molecules26216690 ◽

2021 ◽

Vol 26 (21) ◽

pp. 6690

Author(s):

Steffen Merz ◽

Jie Wang ◽

Petrik Galvosas ◽

Josef Granwehr

Keyword(s):

Ionic Liquids ◽

Carbon Black ◽

Porous Electrode ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Porous Electrodes ◽

Aggregation Behavior ◽

Magic Angle ◽

Additional Parameter ◽

Inversion Algorithm

Electrolytes based on ionic liquids (IL) are promising candidates to replace traditional liquid electrolytes in electrochemical systems, particularly in combination with carbon-based porous electrodes. Insight into the dynamics of such systems is imperative for tailoring electrochemical performance. In this work, 1-Methyl-1-propylpyrrolidinium bis(trifluoromethylsulfonyl)imide and 1-Hexyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide were studied in a carbon black (CB) host using spectrally resolved Carr-Purcell-Meiboom-Gill (CPMG) and 13-interval Pulsed Field Gradient Stimulated Echo (PFGSTE) Magic Angle Spinning Nuclear Magnetic Resonance (MAS-NMR). Data were processed using a sensitivity weighted Laplace inversion algorithm without non-negativity constraint. Previously found relations between the alkyl length and the aggregation behavior of pyrrolidinium-based cations were confirmed and characterized in more detail. For the IL in CB, a different aggregation behavior was found compared to the neat IL, adding the surface of a porous electrode as an additional parameter for the optimization of IL-based electrolytes. Finally, the suitability of MAS was assessed and critically discussed for investigations of this class of samples.

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Basic Principles and Recent Results of H Magic-Angle-Spinning and Pulsed Field Gradient Nuclear Magnetic Resonance Studies on Zeolites11'H Mas Nmr Studies on Dehydrated Zeolites

Studies in Surface Science and Catalysis - Proceedings of ZEOCAT 90 ◽

10.1016/s0167-2991(08)62901-8 ◽

1991 ◽

pp. 89-115 ◽

Cited By ~ 23

Author(s):

H. Pfeifer ◽

D. Freude ◽

J. Kärger

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Magic Angle ◽

Nmr Studies ◽

Basic Principles ◽

Magnetic Resonance Studies ◽

Pulsed Field ◽

Angle Spinning

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An insight into the structure of foods using 13C and 1H magic angle spinning (MAS) NMR: Application to wheat dough

Magnetic Resonance in Food Science - Special Publications ◽

10.1039/9781847551252-00043 ◽

2007 ◽

pp. 43-53

Author(s):

E. Alberti ◽

D. Santos

Keyword(s):

Magic Angle Spinning ◽

Mas Nmr ◽

Magic Angle ◽

Wheat Dough ◽

Angle Spinning ◽

Insight Into

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Cross Polarization/Magic Angle Spinning Nuclear Magnetic Resonance (CP/MAS NMR) Spectroscopy

Methods in Lignin Chemistry - Springer Series in Wood Science ◽

10.1007/978-3-642-74065-7_11 ◽

1992 ◽

pp. 146-161 ◽

Cited By ~ 18

Author(s):

G. J. Leary ◽

R. H. Newman

Keyword(s):

Nuclear Magnetic Resonance ◽

Nmr Spectroscopy ◽

Magnetic Resonance ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Magic Angle ◽

Cross Polarization ◽

Angle Spinning ◽

Cp Mas Nmr ◽

Nuclear Magnetic

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Article

Canadian Journal of Chemistry ◽

10.1139/v99-181 ◽

1999 ◽

Vol 77 (11) ◽

pp. 1962-1972

Author(s):

Scott Kroeker ◽

Roderick E Wasylishen

Keyword(s):

Nmr Spectra ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Spin Coupling ◽

Group Symmetry ◽

Magic Angle ◽

Chemical Shielding ◽

Shielding Tensor ◽

Angle Spinning ◽

Spin Spin Coupling

Direct NMR observation of copper-63/65 nuclei in solid K3Cu(CN)4 provides the first experimental example of anisotropic copper chemical shielding. Axially symmetric by virtue of the space group symmetry, the shielding tensor spans 42 ppm, with the greatest shielding when the unique axis is perpendicular to the applied magnetic field. The nuclear quadrupole coupling constant is also appreciable, CQ(63Cu) = -1.125 MHz, reflecting a deviation of the Cu(CN)43- anion from pure tetrahedral symmetry. Spin-spin coupling to 13C nuclei in an isotopically enriched sample is quantified by line-shape simulations of both 13C and 63/65Cu magic-angle spinning (MAS) NMR spectra to be 300 Hz. It is shown that this information is also directly available by 63/65Cu triple-quantum (3Q) MAS NMR. The relative merits of these three approaches to characterizing spin-spin couplings involving half-integer quadrupolar nuclei are discussed. Chemical shielding tensors for nitrogen-15 and carbon-13 are obtained from NMR spectra of non-spinning samples, and are compared to those of tetrahedral group 12 tetracyanometallates. Finally, 2J(63/65Cu,15N) detected in 15N MAS experiments are found to be 19 and 20 Hz for the two crystallographically distinct cyanide ligands.Key words: NMR, quadrupolar nucleus, chemical shielding tensor, multiple-quantum magic-angle spinning, metal cyanide, spin-spin coupling.

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