Detection of artificial enamel caries-like lesions with a blue hydroxyapatite-binding porosity probe

Frank Lippert; Jennifer S Eder; George J Eckert; Jonathan Mangum; Kerry Hegarty

doi:10.1016/j.jdent.2023.104601

Detection of artificial enamel caries-like lesions with a blue hydroxyapatite-binding porosity probe

J Dent. 2023 Aug:135:104601. doi: 10.1016/j.jdent.2023.104601. Epub 2023 Jun 25.

Authors

Frank Lippert¹, Jennifer S Eder², George J Eckert³, Jonathan Mangum⁴, Kerry Hegarty⁴

Affiliations

¹ Department of Cariology, Operative Dentistry and Dental Public Health, Oral Health Research Institute, Indiana University School of Dentistry, 415 Lansing Street, Indianapolis, IN 46202, USA. Electronic address: flippert@iu.edu.
² Department of Cariology, Operative Dentistry and Dental Public Health, Oral Health Research Institute, Indiana University School of Dentistry, 415 Lansing Street, Indianapolis, IN 46202, USA.
³ Department of Biostatistics, Indiana University School of Medicine, 410 W. Tenth St., Suite 3000, Indianapolis, IN 46202, USA.
⁴ Incisive Technologies Pty Ltd, Level 4, 71 Collins Street, Melbourne, Victoria 3000, Australia.

PMID: 37364728
DOI: 10.1016/j.jdent.2023.104601

Abstract

Objectives: This in vitro study investigated the ability of a blue protein-based hydroxyapatite porosity probe to selectively detect artificial enamel caries-like lesions of varying severities.

Methods: Artificial caries-like lesions were formed in enamel specimens using a hydroxyethylcellulose-containing lactic acid gel for 4/12/24/72 or 168 h. One untreated group was used as a control. The probe was applied for 2 min and unbound probe rinsed off with deionized water. Surface color changes were determined spectrophotometrically (L*a*b* color space) and with digital photography. Lesions were characterized using quantitative light-induced fluorescence (QLF), Vickers surface microhardness, and transverse microradiography (TMR). Data were analyzed using one-way ANOVA.

Results: Digital photography did not reveal any discoloration in unaffected enamel. However, all lesions stained blue with color intensity positively correlated with demineralization times. The color data reflected similar trends: lesions became significantly darker (L* decreased) and bluer (b* decreased), while overall color differences (ΔE) increased significantly after probe application (4-h lesion, mean±standard deviation: ΔL*=-2.6 ± 4.1/Δb*=0.1 ± 0.8/ΔE=5.5 ± 1.3 vs. 168-h lesion: ΔL*=-17.3 ± 1.1/Δb*=-6.0 ± 0.6/ΔE=18.7 ± 1.1). TMR analysis revealed distinct differences in integrated mineral loss (ΔZ) and lesion depth (L) between demineralization times (4-h lesion: ΔZ=391±190 vol%min × µm/L = 18.1 ± 10.9 µm vs. 168-h lesion: ΔZ=3606±499 vol%min × µm/L = 111.9 ± 13.9 µm). QLF and microhardness were also able to differentiate between demineralization times. L and ΔZ strongly correlated (Pearson correlation coefficient [r]) with Δb* (L vs. Δb*: r=-0.90/ΔZ vs. Δb*: r=-0.90), ΔE (r = 0.85/r = 0.81), and ΔL* (r=-0.79/r=-0.73).

Conclusion: Considering the limitations of this study, the blue protein-based hydroxyapatite-binding porosity probe appears to be sufficiently sensitive to distinguish between unaffected enamel and artificial caries-like lesions.

Clinical significance: Early detection of enamel caries lesions remains one of the most critical aspects in the diagnosis and management of dental caries. This study highlighted the potential of a novel porosity probe in detecting artificial caries-like demineralization by objective means.

Keywords: Demineralization; Dental caries; Detection; Dye; Enamel; Probe; Staining.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Dental Caries Susceptibility
Dental Caries* / diagnostic imaging
Dental Caries* / drug therapy
Durapatite / therapeutic use
Humans
Porosity
Tooth Demineralization* / diagnostic imaging
Tooth Demineralization* / pathology

Substances

Durapatite