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2000 Fiscal Year Final Research Report Summary

Development of new method for the treatment of halitosis using molecular biological technique

Research Project

Project/Area Number 11672051
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeSingle-year Grants
Section一般
Research Field 矯正・小児・社会系歯学
Research InstitutionKYUSHU UNIVERSITY

Principal Investigator

OHO Takahiko  University Dental Hospital, KYUSHU UNIVERSITY, Assistant Professor, 歯学部・附属病院, 講師 (50160940)

Co-Investigator(Kenkyū-buntansha) SHIMAZAKI Yoshihiro  Faculty of Dental Science, KYUSHU UNIVERSITY, Research Associate, 大学院・歯学研究院, 助手 (10291519)
Project Period (FY) 1999 – 2000
KeywordsHalitosis / Volatile sulfur compounds / Hydrogen sulfide / Methyl mercaptan / Tongue coating / Periodontitis
Research Abstract

Oral malodor is mainly associated with the condition of the oral cavity and is originates from a variety of products produced by the bacterial metabolism of amino acids in materials such as food debris, desquamated cells from oral mucosa and leukocytes that accumulate in the mouth. These metabolites include volatile sulfur compounds (VSC), indole, skatole, amines and ammonia. Of these compounds, VSC are the main cause of oral malodor.
In this study, the characteristics of patients complaining of halitosis were examined and the diagnostic accuracy of methods of measuring halitosis was evaluated. The organoleptic test revealed that 55% of the subjects had no or slight odor. There was a significant correlation between the organoleptic score and the total VSC level determined by other methods. The amount of tongue coating was significantly greater in the halitosis-positive group than in the halitosis-negative group, whereas there was no difference in the salivary flow rate between the two groups.
The ability of periodontopathic Porphyromonas gingivalis to produce methyl mercaptan was examined. The invasive strain W83 and W50 produced large amounts of methyl mercaptan. We cloned and sequenced the gene encoding L-methionine-α-deamino-γ-mercaptomethane-lyase (METase) from P.gingivalis W83. We also constructed a METase-deficient mutant of P.gingivalis W83. The mutant showed a marked decrease in the formation of methyl mercaptan from L-methionine and decreased virulence compared with the wild-type strain W83. Inactivation of METase may be effective for the inhibition of oral malodor.

  • Research Products

    (9 results)

All Other

All Publications (9 results)

  • [Publications] 於保孝彦: "口臭発生のメカニズム"歯界展望. 93・1. 1178-1179 (1999)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Yoshimura,M. et al.: "Formation of methyl mercaptan from L-methionine by Porphyromonas gingivalis."Infect.Immun.. 68・12. 6912-6916 (2000)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] 於保孝彦: "口臭について"九州大学健康科学センターコミュニケーション誌CAMPUS HEALTH. 14. 6-7 (2000)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Oho,T. et al.: "Psychological condition of patients complaining of halitosis."J.Dent.. (in press).

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Oho,T. et al.: "Characteristics of patients complaining of halitosis and the usefulness of gas chromatography for diagnosing halitosis."Oral Surg.Oral Med.Oral Pathol.Oral Radiol.Endod.. (in press).

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] 古賀敏比古 ら: "歯周病-新しい治療を求めて"先端医療技術研究所. 536 (2000)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Yoshimura, M.et al.: "Formation of methyl mercaptan from L-methionine by Porphyromonas gingivalis."Infect.Immun.. 68. 6912-6916 (2000)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Oho, T.et al.: "Psychological condition of patients complaining of halitosis."J.Dent.. (in press).

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Oho, T.et al.: "Characteristics of patients complaining of halitosis and the usefulness of gas chromatography for diagnosing halitosis."Oral Surg.Oral Med.Oral Pathol.Oral Radiol.Endod. (in press).

    • Description
      「研究成果報告書概要(欧文)」より

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Published: 2002-03-26  

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