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Biochemical characterisation of carious dentine zones using Raman spectroscopy
M Alturki1, G Koller2, F Warburton3
1Centre of Oral Clinical Translational Sciences, Faculty of Dentistry, Oral & Craniofacial Sciences, King's College London, London, United Kingdom; Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia.
Journal of Dentistry
|December 14, 2020
Summary
Objective discrimination of carious dentine is possible using Raman spectroscopy. This technique correlates biochemical changes (amide I:phosphate ratios) with Knoop microhardness, aiding caries management.
Area of Science:
- Biochemistry
- Materials Science
- Dental Research
Background:
- Caries management traditionally relies on subjective hardness assessment.
- Biochemical alterations offer objective discrimination of carious lesion zones.
Purpose of the Study:
- To correlate biochemical proportions (amide I and phosphate) with Knoop microhardness in carious dentine.
- To evaluate Raman spectroscopy for objective carious tissue discrimination.
Main Methods:
- High-resolution Raman spectroscopy analyzed 423 scan points from 20 carious dentine samples.
- Calculated amide I (1650 cm⁻¹) to phosphate (960 cm⁻¹) peak ratios.
- Correlated ratios with Knoop microhardness measurements along lesion paths.
Main Results:
- Logistic regression revealed clear correlations between Knoop microhardness and Raman peak ratios.
- High sensitivity (81.5%) and specificity (92.7%) for discriminating caries-infected from caries-affected dentine.
- Lower specificity (2.7%) for discriminating caries-affected from sound dentine.
Conclusions:
- Non-contact Raman spectroscopy objectively discriminates carious dentine lesion zones in vitro.
- Amide I:phosphate ν₁ ratios serve as objective markers for caries excavation endpoints.
- Potential for in vitro and in vivo application in selective caries removal.
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