Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Sep;26(9):5847-5855.
doi: 10.1007/s00784-022-04541-7. Epub 2022 May 19.

Attenuation of near-ultraviolet, visible and near-infrared light in sound and carious human enamel and dentin

Katrin Berghammer  1 , Friederike Litzenburger  2 , Katrin Heck  2 , Karl-Heinz Kunzelmann  2
Affiliations

Attenuation of near-ultraviolet, visible and near-infrared light in sound and carious human enamel and dentin

Katrin Berghammer et al. Clin Oral Investig. 2022 Sep.

Abstract

Objectives: This in vitro study aimed to investigate the optical attenuation of light at 405, 660 and 780 nm sent through sound and carious human enamel and dentin, including respective individual caries zones, as well as microscopically sound-appearing tissue close to a carious lesion.

Materials and methods: Collimated light transmission through sections of 1000-125-µm thickness was measured and used to calculate the attenuation coefficient (AC). The data were statistically analysed with a MANOVA and Tukey's HSD. Precise definition of measurement points enabled separate analysis within the microstructure of lesions: the outer and inner halves of enamel (D1, D2), the translucent zone (TZ) within dentin lesions and its adjacent layers, the enamel side of the translucent zone (ESTZ) and the pulpal side of the translucent zone (PSTZ).

Results: The TZ could be distinguished from its adjacent layers and from caries-free dentin at 125 µm. Sound-appearing dentin close to caries lesions significantly differed from caries-free dentin at 125 µm. While sound and carious enamel exhibited a significant difference (p < 0.05), this result was not found for D1 and D2 enamel lesions (p > 0.05). At 405 nm, no difference was found between sound and carious dentin (p > 0.05).

Conclusions: Light optical means enable the distinction between sound and carious tissue and to identify the microstructure of dentin caries partially as well as the presence of tertiary dentin formation. Information on sample thickness is indispensable when interpreting the AC.

Clinical relevance: Non-ionising light sources may be suitable to detect lesion progression and tertiary dentin.

Keywords: Caries detection; Caries zones; Dentin caries; Enamel caries; Tertiary dentin; Transillumination.

PubMed Disclaimer

Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Measurement points in a caries-free (CF) sample and a carious (CAR) sample. SE, sound enamel; SD, sound dentin; CE, carious enamel; D1, enamel caries outer half; D2, enamel caries inner half; CD, carious dentin; PSTZ, pulpal side of the translucent zone; TZ, translucent zone; ESTZ, enamel side of the translucent zone
Fig. 2
Fig. 2
Box plot of the attenuation coefficients of sound and carious enamel and dentin at 405 nm, 660 nm and 780 nm
Fig. 3
Fig. 3
Mean attenuation coefficients of sound dentin (SD) and different zones of carious dentin (PSTZ, pulpal side of the translucent zone; TZ, translucent zone; ESTZ, enamel side of the translucent zone) in relation to the sample thickness and wavelength
See this image and copyright information in PMC

References

    1. Kocak N, Cengiz-Yanardag E. Clinical performance of clinical-visual examination, digital bitewing radiography, laser fluorescence, and near-infrared light transillumination for detection of non-cavitated proximal enamel and dentin caries. Lasers Med Sci. 2020;35(7):1621–1628. doi: 10.1007/s10103-020-03021-2. - DOI - PubMed
    1. Pitts NB, Rimmer PA. An in vivo comparison of radiographic and directly assessed clinical caries status of posterior approximal surfaces in primary and permanent teeth. Caries Res. 1992;26(2):146–152. doi: 10.1159/000261500. - DOI - PubMed
    1. Poorterman JH, Aartman IH, Kalsbeek H. Underestimation of the prevalence of approximal caries and inadequate restorations in a clinical epidemiological study. Community Dent Oral Epidemiol. 1999;27(5):331–337. doi: 10.1111/j.1600-0528.1999.tb02029.x. - DOI - PubMed
    1. Poorterman JH, et al. Value of bite-wing radiographs in a clinical epidemiological study and their effect on the DMFS index. Caries Res. 2000;34(2):159–163. doi: 10.1159/000016584. - DOI - PubMed
    1. Neuhaus KW, et al. Novel lesion detection aids. Monogr Oral Sci. 2009;21:52–62. doi: 10.1159/000224212. - DOI - PubMed