Measurement of Enamel Demineralization using Microradiography and Confocal Microscopy

Abstract

Substantial amounts of tooth minerals are lost during dental caries formation. Transversal microradiography, a well-accepted method used to quantify mineral loss, is a time-consuming technique which requires a thin enamel section (100 µm) and involves the use of x-rays. In an attempt to solve these difficulties, a procedure has been developed in which a human tooth specimen with demineralized enamel is cut in half (HT), stained with a fluorescent dye (rhodamine B) and analyzed using a laser scanning confocal microscope. A series of three studies was conducted to correlate measurements of enamel demineralization obtained from enamel thin (100 µm) sections (TS) using transversal microradiography with three parameters (area of the lesion; total and average dye fluorescence intensities) measured on the same TS or on a thicker section (HT) of the same specimen by laser scanning confocal microscopy. Results showed that a 0.1 mM rhodamine B solution provided the most adequate imaging conditions for confocal microscopy. Pearson’s correlation coefficients, calculated between microradiography and confocal microscopy data obtained using a 0.1 mM rhodamine B solution, were: ΔZ vs. HT lesion area = 0.95; ΔZ vs. HT total fluorescence = 0.80; ΔZ vs. HT average fluorescence = 0.74; ΔZ vs. TS lesion area = 0.95; ΔZ vs. TS total fluorescence = 0.74; ΔZ vs. TS average fluorescence = 0.55. All these correlations coefficients were statistically significant (p < 0.01). It is concluded that in enamel demineralization studies statistically significant correlations exist between parameters measured using transversal microradiography and parameters quantified using confocal microscopy.

Sealing of Minimally Invasive Class II Fillings (slot) Using an Adhesive Patch: Sealant Margin Extension for Prevention

“…[17][18] In a recent laboratory study, the effect of seven surface sealants on the marginal seal of mixed Class V hybrid resin composite restorations was assessed. 16 Although the results showed a significant reduction in microleakage scores and a potential for improving marginal integrity, a remarkable degree of microleakage was still noticeable. None of the tested materials was completely resistant to dye penetration.…”

“…The techniques of bonding and re-bonding have been recommended to increase marginal integrity. [15][16] Applying filled and unfilled lowviscosity resins to the restoration material surface and surrounding tooth structures has been proposed as a means to infiltrate possible interfacial gaps and promote sealing, thereby reducing the risk of microleakage and caries formation. The use of pit and fissure sealant materials has also been investigated.…”

“…Two sections 0.5 mm thick were polished with silicon carbide paper (4000 grit). Based on the method described by Fontana and others, 16 sections were analyzed using a confocal laser scanning microscope (Zeiss LSM 510; Carl Zeiss, Jena, Germany) without staining in order to measure autofluorescence of the demineralization. 20 Using the measuring tool of the Zeiss LSM 510 image browser software (Carl Zeiss), demineralization depth was measured at the margins of the patch and filling.…”

Qualitative analysis of re mineralized carious lesions subjected to fluoride supplement through confocal laser scanning microscope

“…As described by Fontana, 0.1 mM rhodamine B dye was used and lesion area, total fluorescence and average fluorescence were evaluated. Lesion area was the confocal parameter that showed the strongest correlation with microradiography, followed by total lesion fluorescence [8,10].…”

“…Monitoring demineralization and remineralization of dental hard tissues is essential for the prevention and minimally invasive treatment of dental caries and hypersensitivity [8]. Light based methods used for the detection of dental caries induced enamel demineralization are Conventional radiography, micro radiography, Digital Imaging Fiber Optic Trans illumination Imaging [DIFOTI], laser induced fluorescence [DIAGNO dent], and quantitative light-induced fluorescence [QLF].…”