High-resolution electron microscopy of crystal contact in the demineralized dentine

The mechanism of the dimensional increase in demineralized dentine crystals was investigated using a high-resolution transmission electron microscope. Lattice fringes were observed even in the demineralized crystals. The characteristics of demineralized dentine crystals mainly consisted of a partial disappearance of their lattice fringes along their lateral surface. High-resolution transmission electron microscopy also revealed that an intricate association between partially demineralized crystals occurred at the interface where incoherent or coherent tilt boundary, the dislocation of lattice fringes appeared. The present findings suggest that the dimensional increase in carious dentine could be brought by a crystal fusion.