Relationship between oral miniature area pH and its microbial flora.

Research Project

Project/Area Number	60304074
Research Category	Grant-in-Aid for Co-operative Research (A)
Allocation Type	Single-year Grants
Research Field	Functional basic dentistry
Research Institution	TOHOKU UNIVERSITY
Principal Investigator	HORIUCHI Hiroshi Professor, Tohoku University School of Dentistry, 歯学部, 教授 (00013962)
Co-Investigator(Kenkyū-buntansha)	YAMADA Tadasi MAITA Ei Professor, Tohoku University School of Dentistry Assistant Professor, Tohoku Uni, 歯学部, 教授 (50005021) 星野悦郎新潟大学, 歯学部, 教授 (90124619) KATAYAMA Tsuyosi HOSINO Professor, School of Dentistry, Iwate Medical College Professor, Niigata Univers, 歯学部, 教授 (00001967) 高江洲義矩東京歯科大学, 歯学部, 教授 (60048303) ONOSE Hideo TAKAESU Yo Professor, School of Dentistry, Nihon University Professor, Tokyo Dental College, 歯学部, 教授 (70059426) KIMURA Kouhei NISIMAKI Lecturer, Tohoku University School of Dentistry Assistant, Tohoku University Sch (40108551) ENDOU Hideaki Assistant, Tohoku University School of Dentistry
Project Period (FY)	1985 – 1986
Project Status	Completed (Fiscal Year 1986)
Budget Amount *help	¥5,800,000 (Direct Cost: ¥5,800,000) Fiscal Year 1986: ¥2,100,000 (Direct Cost: ¥2,100,000) Fiscal Year 1985: ¥3,700,000 (Direct Cost: ¥3,700,000)
Keywords	ISFET / miniature area pH / microbial flora / acidogenicity / fluoride / ionomer cement / periodontal pocket / 庶糖
Research Abstract	The pH shift of oral miniature areas is closely related to their pathological condition. The plaque-enamel interface, the inside of periodontal pockets, the gingival sulcus near the margin of restorations and interdental spaces are the miniature areas interested. The purpose of this research is to elucidate the relationship between the miniature area pH and its microbial flora. The bacterial composition of human dental plaque formed on enamel and on hydrogen-ion sensitive field effect transistor electrode(ISFET) were compared by Hosino. He found that the composition of plaque on the ISFET was the same as that on enamel. Hosino, Yamada, and Nisimaki measured the decrease of pH produced by various kinds of sugar and proposed that the ISFET method was useful to examine the acidogenicity of foods. Suppression of acid production by fluoride was found by Takaesu using indwelling ISFET. Onose found that decrease of pH produced by sucrose in plaque formed on the ionomer cement was smaller than that on the enamel. Katayama investigated that the maturity of plaque closely related to the acidogenicity. Kimura measured the pH of gingival sulcus and the pH fluctuation that was caused by food and drinks. Microbial flora of periodontal pockets was investigated by Endo, Maita and Horiuchi. The pH of periodontal pockets was weak acidic. Major flora in the periodontal pocket consisted of spaces that had affinity for bacteroides medium and mitis-salivalius medium. Radiotelemetry of intraoral pH measurement was also investigated.