Scanning electron microscopy subsequent to a combined treatment of NaOCl and EDTA in some non-collagenous calcified matrixes

Using backscattered electron (BSE) imaging and scanning electron microscopy , subsequent to a combined treatment of sodium hypochlorite (NaOCl) and eth ylenediamine tetra-acetic acid (EDTA) or only with EDTA etching, we observe d some structures of non-collagenous calcified matrixes with the aim of rev ealing the correlation of deposition between calcification degree and organ ic amount. In human tooth enamel, the NaOCl-EDTA method eroded more intensi vely the hypocalcified prisms of enamel tufts containing a relatively large amount of EDTA-insoluble organic matter than the hyper-calcified normal pr ismatic enamel containing a small amount of the organic matter. Afibrillar cementum, one of the non-collagenous calcified tissues similar to the ename l, has been reported to consist of organic-rich and poor incremental lamell ae. The BSE imaging showed an alternation pattern of hypocalcification and hypercalcification. The hypocalcified lamellae were retained by EDTA etchin g, while the hypercalcified lamellae showed a resistance against the NaOCl- EDTA method. In the non-collagenous calcareous concretions of human pineal body, organic-rich and poor, and hyper- and hypocalcified incremental lamel lae have been reported. The deposition pattern of calcification degree and organic amount was similar to that in afibrillar cementum, and the hypercal cified lamellae showed a resistance against the NaOCl-EDTA method. In concl usion, the high and the lower calcified regions of non-collagenous calcifie d matrixes contained smaller and larger amounts of EDTA-insoluble organic m atter respectively. Moreover, scanning electron microscopy subsequent to th e NaOCl-EDTA method corresponding to the BSE imaging clearly showed fine ca lcified structures compared with the BSE imaging.