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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
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Molecular Insights into Covalently Stained Carious Dentine Using Solid-State NMR and ToF-SIMS.
Ulrica S Almhöjd1, Peter Lingström, Åke Nilsson
1Department of Cariology, Institute of Odontology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Caries Research
|May 15, 2017
Summary
Hydrazine-based dyes selectively stain carious dentine, not healthy dentine. This research confirms covalent bonding, offering a promising solution to prevent overexcavation during dental procedures.
Area of Science:
- Biomaterials Science
- Dental Research
- Analytical Chemistry
Background:
- Current dyes for carious dentine lack specificity, leading to overexcavation.
- Selective staining of carious dentine remains a significant clinical challenge.
- Hydrazine-based compounds show potential for specific binding to carious dentine via covalent bonds.
Purpose of the Study:
- To investigate covalent bond formation between carious dentine and 15N2-hydrazine.
- To evaluate the specificity of 15N2-labelled Lucifer Yellow for carious dentine.
- To determine if hydrazine-based dyes can differentiate between carious and normal dentine.
Main Methods:
- Utilized powdered dentine from carious and normal teeth.
- Exposed dentine samples to 15N2-hydrazine and 15N2-labelled Lucifer Yellow.
- Analyzed staining reactions using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and nuclear magnetic resonance (NMR) spectroscopy (13C and 15N).
Main Results:
- Both 15N2-hydrazine and 15N2-labelled Lucifer Yellow demonstrated binding exclusively to carious dentine.
- No binding was observed with normal dentine for either compound.
- Spectroscopic analyses confirmed the formation of covalent bonds with carious dentine.
Conclusions:
- Hydrazine-based dyes, including Lucifer Yellow, exhibit high selectivity for carious dentine.
- These dyes can effectively stain carious dentine while leaving normal dentine unstained.
- The findings support the use of hydrazine-based dyes to improve the accuracy of caries detection and excavation.
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