Biomedical subjects

H Yukizaki

Publications and source records attributed to H Yukizaki.

3 recordsLinked to original sources

PubMed1998

Relationship between the electrical resistivity of enamel and the relative humidity.

The present study was carried out to investigate the relationship between the relative humidity and the electrical resistivity of enamel in vitro. The electrical resistivity of enamel samples was measured in a thermo-hygrostat where the relative humidity varied between 60% and 90%, with the measurements carried out first in a descending direction and then in an ascending direction. When the electrical resistivity was measured from a low to high relative humidity in an ascending direction, a higher value of electrical resistivity was always obtained in comparison to that when measured in the reverse descending direction. The difference between the mean electrical resistivity in an ascending and a descending direction increased in proportion to the relative humidity. These findings suggest that the diffusion of electrolytes and water in enamel is sensitive to changes in the relative humidity.

Adult↗

PubMed1997

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.

Dental Caries↗

PubMed1986

Electroacupuncture increases ipsilaterally tooth pain threshold in man.

The effect of electroacupuncture stimulation applied to a unilateral Ho-ku point on the human tooth pain thresholds was studied by electrically stimulating bilateral canines. In six of ten subjects tested, the tooth pain threshold was elevated ipsilaterally but was unchanged contralaterally during and after the electroacupuncture. In the remaining four, neither the ipsilateral nor the contralateral canine showed any change in the pain threshold by the electroacupuncture. The ipsilateral increase of the tooth pain threshold may be explained by a mechanism by which electroacupuncture stimulation of one Ho-ku point causes various pain suppression centers to release ipsilaterally endogenous opioids.

Acupuncture Therapy↗