Application of confocal laser scanning microscopy to enamel caries.

Abstract

: To assess the usefulness of confocal laser scanning microscopy (CLSM) in the examination of enamel caries, we prepared ground sections of carious teeth, stained them with fuchsin, observed them with CLSM and then compared the results with light microscopy and contact microradiography findings. The following results were obtained : 1 ) Sound enamel could not be visualized using CLSM. 2 ) In enamel caries, a surface layer, the body of the lesion and a dark zone were observed, but a translucent zone was hardly observed with CLSM. 3 ) Subsurface decalcification, which was observed with CLSM, appeared as destruction of the enamel rods, slightly toward the dentin side from the surface layer. 4) In the areas adjoining the lesion, disruption at the center or the margin of enamel rods was seen. 5) Lesions were also present alongside enamel lamella-like structures that had formed in the enamel close to the dentin. These lesions had extended laterally, engulfing the center or the margin of enamel rods near the enamel lamellalike structures. The lesions were also enlarged in the dentin adjacent to the structure. However, these lesions were not observed by light microscopy or contact microradiography. In summary, observation of enamel caries by CLSM revealed that it can give the same sort of findings as conventional histological visualization.In addition, it may also be possible to obtain three-dimensional findings with CLSM that are difficult to observe by conventional means.Therefore, we conclude that CLSM is useful for observing enamel caries.

A Histological Study of the Organic Elements in the Human Enamel focusing on the Extent of the Odontoblast Process

“…The specimens were then dehydrated, dried, mounted, examined and the tomographic images were analysed at 0.5-2 pm intervals using an Olympus GB-200 CLSM (argon ion laser, excitation wave length: 488 nm; using CH1: 0-515 and BP-535, CH2: 0-570 and 0-590 filters; Olympus, Tokyo, Japan) connected to an image analysis system (CLSM-GB 200 application ver. 2.13; Compaq Prolinea-4100 computer, USA), and photographed using an Avio FR-3000 film recorder (Avionics, Tokyo, Japan) by modifying the methods proposed for studying tooth decay (Tanaka and Nishikawa, 1995). Additionally, some specimens from undemineralised samples were also ground, coated either with gold in the Eiko IB-3 ion coater or with carbon in a Hitachi HUS-4GB evaporator, and prepared for SEM and EDS X-ray microprobe analysis.…”

“…Recently, confocal scanning microscopy, in particular confocal laser scanning microscopy (CLSM) connected to an image analysis system was applied to non-destructive specimens for tomographic and three-dimensional study of hard tissues (Boyde and Martin, 1984;Carlsson et al, 1985;Howard et al, 1985;Boyde, 1986;Benn and Watosson, 1989; Nakamura and Kawata, 1990; Kodaka, Debari and Yamade, 1991; Ohya et al, Tanaka and Nishikawa, 1995). In the present study, the relationships between the organic elements included in the human enamel and the odontoblast process extending in the dentine were initially examined using CLSM.…”

Plastic casts and confocal laser scanning microscopy applied to the observation of enamel tubules in the red Kangaroo (Macropus rufus)

“…The PC technique produces casts of the internal structures in hard tissue, and scanning microscopy of the casts enable 3‐D observations of tubular structures or hypocalcific regions in dental tissue (PC‐SEM method; Weber, 1983; Wang et al ., 1985; Lester et al ., 1987; Sahni and Lester, 1988; Yoshida et al ., 1993; Suzuki et al ., 1996). The CLSM gives images of fluorescent regions in ground sections of teeth treated by the Villanueva bone‐stain (VBS) solution (Watson, 1991; Kabasawa et al ., 1995; Tanaka and Nishikawa, 1995), and dentinal tubules and enamel spindles can be clearly observed (VBS‐CLSM method; Watson, 1991; Kabasawa et al ., 1995). A 3‐D reconstruction of the fluorescent structures is also possible by image processing software.…”