The author discovered in 1970 that L-carnosine promotes granulation,  and in 1975 identified this substance as a physiological active peptide which facilitates spontaneous healing.  In 1978 he demonstrated that when sprinkled over dental surgical wounds, inflammation was conspicuously suppressed and rapid healing obtained without the use of other analgesic and antiinflammatory agents. The role of L-carnosine as a chemical mediator which promotes the healing of inflammation was thus clinically proven. The biological action of spontaneous healing, a vital response, is not elucidated by today's periodontology, and with overly narrow and fragmentarily conducted research, it has not been possible to understand the actual machanism involved. In the absence of effective medicines, clinically this means trying a flap operation, gingivectomy, etc., in the hope of promoting spontaneous healing. Furthermore, neither looking at the results obtained from numerous biochemical analyses nor enumerating endogenous and exogenous factors provides a direct picture of clinical conditions sufficient to fathom the cause of the decline in the spontaneous healing function of the gims, said to underlie periodontitis. Now, however, promotion of such healing by L-carnosine has made it possible to account for the whole healing process from the early inflammation and exudation through granulation to recovery. This has enabled the author to clear up the confusion of theories regarding the cause of pyorrhea, realize that a functional decline in spontaneous healing of the gums is indeed the cause, and clarify a fundamental method of fostering such healing and thus a cure of the condition. 13 cases cured using L-carnosine are given to corroborate tlis assertion. (MITSUKOSHI PRIZE OF MEDICINE 1977)
1. The solubility of zinc phosphate cement From the experimental results, it is proved that the solubility of zinc phosphate cement becomes largest in buffered solution pH 4, the solubility of Zn and Mg amounting to 1440-1580μg/cm2. But, in artificial saliva and buffered solution pH 9, both Zn and Mg show small values. Especially, the solubility proves to be small in alkaline solution. Again, all 3 kinds of cement show similar values in solubility. The solubility shown above proves to be very large, as compared with those obtained in the case, soaked in the distilled water for a day , though in buffered solution pH 9, both Zn and Mg respectively show the values similar to those in the distilled water. Again, it is proved that H3PO4 in zinc phosphate cement is slightly soluble in buffered solution pH 4 , but not determinable. 2. The solubility of carboxylate cement As shown in Figs. 3 & 4, the solubility of Zn and Mg of both kinds of cement becomes largest in buffered solution pH 4, Zn and Mg amounting to 1210-1465 μg/cm2, a value similar to that of zinc phosphate cement. The solubility proves to be comparatively large both in artificial saliva and buffered solution pH 9, too. Especially in buffered solution pH 9, both Zn and Mg show 15.0-45.5μg/cm2, and it is presumed that the solubility of this kind of cement is large in alkaline solution. Again, it is proved that in any solution the solubility is very large, as compared with those obtained in the distilled water. On the other hand, -COOH of this cement is not detectable in any solution but in buffered solution pH 4 . 3. The solubility of silicate cement The solubility of Si and Al of this cement shows comparatively a large value, especially, Al, approximately 305μg/cm2. But in artificial saliva and buffered solution pH 9, Al is not detectable, though Si shows 14.0 and 26.0μg/cm2 in the respective solutions. The above-shown values, in comparison with those obtained by 7-day soaking in the distilled water, prove that Si shows small values in any solution, and Al, which shows a large value in buffered solution pH 4, is not detected in both buffered solution pH 9 and artificial saliva. The presumption, then, is that silicate cement, soluble in buffered solution pH 4, is hardly soluble in both artificial saliva and buffered solution pH 9, though the reason for this is not traceable. In any case, it is proved that the solubility of zinc phosphate, carboxylate and silicate cement is large in the acid region. Again, Mg of zinc phosphate and carboxylate cement shows very large solubility, considering their composition shown in Table 1. Especially, carboxylate cement proves to have large solubility in the alkaline region. As to silicate cement, the solubility of Na is proved to be large.
The authors reach the following conclusion as the result of the examination on the physical properties of vinyl silicone impression materials in comparison with those of other elastomers. 1) The materials are slightly late in the beginning time of setting, but quick in the setting finish, as compared with the condensation typed silicone. 2) The materials are excellent in dimensional stability, as compared with other elastomers. 3) The materials are not only excellent in elasticity, but very small in permanent deformation, as compared with other elastomers. 4) From the results shown above, it is presumed that the materials show preferable impression accuracy even in the case a large undercut is necessary.
In studying the characteristics of the dental amalgam restorations of 64 dental students, it is concluded that : (1) sporadic use of the microscope (20×) does not help to improve the performance of dental amalgam restorations; (2) it is hypothesized that continued use of the microscope during work performance may result in improved work performance; and (3) it is hypothesized that tactile and kinesthetic rather than visual abilities are the dominating factors in dental psychomotor performance.