Chemo-mechanical characterization of carious dentine using Raman microscopy and Knoop microhardness

TY - JOUR

T1 - Chemo-mechanical characterization of carious dentine using Raman microscopy and Knoop microhardness

AU - Alturki, M.

AU - Koller, G.

AU - Almhöjd, U.

AU - Banerjee, A.

PY - 2020/5/1

Y1 - 2020/5/1

N2 - One of the aims in the clinical operative management of dental carious lesions is to remove selectively the highly infected and structurally denatured dentine tissue, while retaining the deeper, repairable affected and intact, healthy tissues for long-term mechanical strength. The present study examined the correlation of chemical functional groups and the microhardness through the different depths of a carious lesion using Raman spectroscopy and Knoop microhardness testing. The null hypothesis investigated was that there was no correlation between Raman peak ratios (amide I: phosphate ν1) and equivalent Knoop microhardness measurements. Ten freshly extracted human permanent teeth with carious dentine lesions were sectioned and examined using high-resolution Raman microscopy. The ratio of absorbency at the amide I and phosphate bands were calculated from 139 scan points through the depth of the lesions and correlated with 139 juxtaposed Knoop microhardness indentations. The results indicated a high correlation (p < 0.01) between the peak ratio and the equivalent Knoop hardness within carious dentine lesions. This study concluded that Raman spectroscopy can be used as a noninvasive analytical technology for in vitro studies to discriminate the hardness of carious dentine layers using the peak ratio as an alternative to the invasive, mechanical Knoop hardness test.

AB - One of the aims in the clinical operative management of dental carious lesions is to remove selectively the highly infected and structurally denatured dentine tissue, while retaining the deeper, repairable affected and intact, healthy tissues for long-term mechanical strength. The present study examined the correlation of chemical functional groups and the microhardness through the different depths of a carious lesion using Raman spectroscopy and Knoop microhardness testing. The null hypothesis investigated was that there was no correlation between Raman peak ratios (amide I: phosphate ν1) and equivalent Knoop microhardness measurements. Ten freshly extracted human permanent teeth with carious dentine lesions were sectioned and examined using high-resolution Raman microscopy. The ratio of absorbency at the amide I and phosphate bands were calculated from 139 scan points through the depth of the lesions and correlated with 139 juxtaposed Knoop microhardness indentations. The results indicated a high correlation (p < 0.01) between the peak ratio and the equivalent Knoop hardness within carious dentine lesions. This study concluded that Raman spectroscopy can be used as a noninvasive analytical technology for in vitro studies to discriminate the hardness of carious dentine layers using the peak ratio as an alternative to the invasive, mechanical Knoop hardness test.

KW - Amide I

KW - Dentine caries

KW - Knoop microhardness

KW - Phosphate

KW - Raman spectroscopy

UR - http://www.scopus.com/inward/record.url?scp=85086110527&partnerID=8YFLogxK

U2 - 10.1098/rsos.200404

DO - 10.1098/rsos.200404

M3 - Article

AN - SCOPUS:85086110527

SN - 2054-5703

VL - 7

JO - Royal Society open science

JF - Royal Society open science

IS - 5

M1 - 200404

ER -