Laser-induced fluorescence and X-ray spectral analysis of carious process in hard dental tissues.

Morphological and spectral X-ray analysis of carious and noncarious extracted teeth showed the patterns of dentin ossification in caries of different degree. Parietal ectopic ossification of the canal and cavity lumens in stages III and IV dental caries is regarded as a specific structural marker of pathological regeneration. The X-ray spectral analysis showed that the progress of carious process is paralleled by loss of mineral components. Laser-induced fluorescent study of tissues in extracted teeth showed 4 spectral bands corresponding to mineral and protein components of the tooth. The progress of carious process was associated with reduction of the fluorescence intensities of the spectral bands characteristic of dental collagen and mineral components.

Morphological evaluation of cytoarchitectonics of aortic graft at the biotechnological stage with analysis of changes in laser-induced fluorescence spectra.

We performed a fluorescent microscopic examination of human and animal aortic grafts at different stages of decellularization. Treatment of aortic grafts with trypsin/EDTA solution for 48 h leads to their complete decellularization and preserved the connective tissue fiber backbone, which gains a netlike structure. The use of this protocol of decellularization leads to disappearance of subintimal calcium deposits in human aortic grafts. Differences in laser-induced fluorescence spectra of aortas before decellularization and at different stages of this process were revealed. Our findings suggest that the use of fluorescence induced by excimer lasers is promising for identification of the composition of biological tissues, analysis of their state, and the presence of changes.