1961 Volume 49 Issue 6 Pages 693-699
1. Peculiar band-shaped pigmentation of light brown to dark brown color was ob-served at the gingiva in high percentage among Japanese children and the term of “juvenile gingival pigmentation” is proposed.
2. From the incidence of gingival pig-mentation in vitamin C-deficient children, as shown by vitamin C saturation test, as well as by preventive and therapeutic effect of vitamin C on gingival pigmentation, etiology of the juvenile gingival pigmentation is attri-buted to the deficiency of vitamin C.
3. In connection with this problem, the effect of vitamin C on tyrosinase, which plays an important role in melanin formation, was discussed. When ascorbic acid is present in the reaction mixture, DOPA-quinone formed by tyrosinase from DOPA is considered to be reconverted to DOPA by ascorbic acid and the reaction of DOPA to DOPA-chrome ceases.
4. As the daily requirement of vitamin C in Japanese adult and child, 1.4mg. and 1.7mg. per kg. of body weight, respectively, may be recommended from the experiment to keep the saturation level of blood vitamin C. In children, the amount of vitamin C necessary to keep the saturated level of blood vitamin C is higher than that in adults, and the saturated level of blood vitamin C is also higher in children than that in adults. This fact implies that children become more easily deficient in vitamin C than adults and also explains the reason for the markedly high incidence of the gingival pigmentation due to vitamin C-deficiency in children than in adults. The authors wish to express their heartful grati-tude to Dr. K. Kodama, President of Tokushima University, for his continued encouragement and in-terest during the course of this work.
