The Bulletin of Tokyo Medical and Dental University 

About: The Bulletin of Tokyo Medical and Dental University is an academic journal. The journal publishes majorly in the area(s): Tooth mobility & Cancer. It has an ISSN identifier of 0040-8921. Over the lifetime, 509 publications have been published receiving 2872 citations.

Differentiation of two layers of carious dentin by staining.

Abstract: Recently, Kato and Fusayama (I Dent Res 49: 1060-1067, 1970) described two layers of dentin in cavity floors of dog's teeth after they had experimentally softened the dentin by acid. The first decalcified layer was soft with low calcium content and could not be recalcified, although a slight calcium deposition from saliva or capping material sometimes occurred. The second decalcified layer was harder with intermediate decalcification and could be recalcified considerably by vital reaction. In treatment of teeth it is considered preferable to save the second layer which can be recalcified. This study was undertaken to find a means of differentiating the two layers in human carious dentin by use of a dye. A variety of dyes (iodine tincture, merbromin, eosin, safranin, Alcian blue, methyl violet, methylene blue, Rose Bengal, Vermeil, Sudan III, acid fuchsin, and Nile blue) in various solvents were tried, and a 0.5% basic fuchsin-propylene glycol solution was effective. The surfaces of sections of 41 freshly extracted human teeth with dentin caries that did not extend into the pulp were covered with the dye for five seconds and washed with water. The superficial half of the carious dentin was stained distinctly whereas the deeper half was not stained. A distinct boundary separated the two zones. It is not known whether the stained layer corresponds exactly to the first decalcified layer which is dead and not recalcifiable. But it is possible that deterioration of the collagenous organic substance in the highly decayed layer is responsible for the stainability. The physiologic recalcification of dentin is thought to occur only on sound collagen fibers (JOHANSEN and PARK, J Dent Res 40:235-248, 1961; and SOLOMONS, J Biol Chem 235:2502-2506, 1960), therefore, the unstained layer might be an in-

Cortically induced masticatory rhythm and its modification by tonic peripheral inputs in immolbilized cats.

Abstract: Repetitive cortical stimulation induced rhythmical masticatory jaw movement and masseteric nerve activity in cats with the spinal cord sectioned at the C2 level. Jaw depression alone did not induce any rhythmical jaw movement, but it turned the irregular jaw movement evoked by subthreshold cortical stimulation into the regular jaw movement as evoked by suprathreshold cortical stimulation. The cortically induced rhythmical masseseteric nerve activity could be induced even in immobilized condition and after cerebellectomy, although the rhythmical nerve activity was depressed in amplitude and the rhythm became slower than before immobilization. Tonic jaw depression after immobilization facilitated the tonic activity in the masseteric nerve and also induced a remarkable increase in the amplitude of the cortically evoked rhythmical nerve activity and a slight acceleration of the rhythm, leading to the same masticatory rhythm as before immobilization. It was concluded (1) that the cortically induced masticatory rhythm in cats is basically generated centrally and (2) that the tonic inputs from the muscle spindle in the jaw-closing muscles participate in the rhythm formation by supplying tonic excitatory inputs mainly to the jaw-closer motoneuron and also to the central rhythm generator.

Clinical application of arthroscopy in the temporomandibular joint diseases.

Abstract: The author presents the methodology and findings of a procedure for arthroscopic examination of the temporomandibular joint cavity by means of a method of puncture of the temporomandibular joint which he developed. The procedure was based on the temporomandibular joint puncture method and involved the tandem insertion of a puncture needle and sheathed needle into the joint cavity and examination of the cavity and cavity wall under perfusion of physiological saline solution. Color photographs of the findings are presented. The advantages by this method are as follows: 1) Direct observation of the cavity, 2) observation of the movement of the joint, 3) biopsy for histopathologic diagnosis, 4) still and cine photography of the findings. Arthroscopy of the temporomandibular joint is at present being applied clinically and is extremely effective in the diagnosis and selection of therapy. It will not doubt play an important role in the diagnosis of the diseases of the temporomandibular joint in the future.

Studies on medically important flies in Thailand. V. On 32 species belonging to the subfamilies Muscinae and Stomoxyinae including the taxonomic keys (Diptera: Muscidae).

Abstract: Flies from different geographical parts of Thailand were collected to study their medical importance as well as making a zoogeographical study. After examination, 32 species of 10 genera, Orthellia, Mitroplatia, Morellia, Pyrellia, Rypellia, Haematobia, Haematobosca, Stygeromyia, Haematostoma and Stomoxys, belonging to Muscidae were identified and these are reported in this paper. Some of these are newly recorded ones from this country. This study is based on the specimens available in the authors' collection.