根管洗浄剤クロラミンTの機能の解析  [in Japanese] Functional Analysis of Chloramine-T as a Root Canal Irrigant  [in Japanese]

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Author(s)

    • 松井 智 MATSUI Satoshi
    • 日本大学松戸歯学部歯内療法学講座:日本大学口腔科学研究所 Department of Endodontics, Nihon University School of Dentistry at Matsudo:Resarch Institute of Oral Science, Nihon University School of Dentistry at Matsudo
    • 和田 陽子 WADA Yoko
    • 日本大学松戸歯学部歯内療法学講座 Department of Endodontics, Nihon University School of Dentistry at Matsudo
    • 小峯 千明 KOMINE Chiaki
    • 日本大学松戸歯学部歯内療法学講座 Department of Endodontics, Nihon University School of Dentistry at Matsudo
    • 三浦 浩 MIURA Hiroshi
    • 日本大学松戸歯学部歯内療法学講座:日本大学口腔科学研究所 Department of Endodontics, Nihon University School of Dentistry at Matsudo:Resarch Institute of Oral Science, Nihon University School of Dentistry at Matsudo
    • 宇都宮 忠彦 UTSUNOMIYA Tadahiko
    • 日本大学口腔科学研究所:日本大学松戸歯学部口腔病理学講座 Resarch Institute of Oral Science, Nihon University School of Dentistry at Matsudo:Department of Oral Pathology, Nihon University School of Dentistry at Matsudo
    • 辻本 恭久 TSUJIMOTO Yasuhisa
    • 日本大学松戸歯学部歯内療法学講座:日本大学口腔科学研究所 Department of Endodontics, Nihon University School of Dentistry at Matsudo:Resarch Institute of Oral Science, Nihon University School of Dentistry at Matsudo
    • 松島 潔 MATSUSHIMA Kiyoshi
    • 日本大学松戸歯学部歯内療法学講座:日本大学口腔科学研究所 Department of Endodontics, Nihon University School of Dentistry at Matsudo:Resarch Institute of Oral Science, Nihon University School of Dentistry at Matsudo

Abstract

本研究の目的は,クロラミンTの根管洗浄剤としての機能を明らかにすることである.クロラミンTおよびH<sub>2</sub>O<sub>2</sub>から発生したフリーラジカルが,ラット腹直筋におけるタンパク質溶解に及ぼす影響や,ヒト歯根膜培養細胞を用いた細胞毒性試験について,検討を行った.ラット腹直筋の湿重量変化において,クロラミンTおよびH<sub>2</sub>O<sub>2</sub>を1時間作用させたところ,5.0,10.0%のクロラミンTおよび3.0%H<sub>2</sub>O<sub>2</sub>において,湿重量の減少が認められた.しかしながら,0.5,1.0%クロラミンTおよび1.0%H_2O_2を作用させても,湿重量変化は認められなかった.pH値測定において,クロラミンTのpH値は,6.22(0%),6.85(0.5%),7.83(1.0%),9.33(5.0%),9.97(10.0%)を示した.ラット腹直筋をクロラミンTに作用させたとき,pH値は,6.30(0%),7.07(0.5%),7.45(1.0%),7.52(5.0%),7.51(10.0%)に変化した.またH<sub>2</sub>O<sub>2</sub>では,6.22(0%),5.20(1.0%),4.65(3.0%)を示した.ラット腹直筋にH<sub>2</sub>O<sub>2</sub>を作用させることで,6.54(0%),6.84(1.0%),6.72(3.0%)に変化した.不対電子の検出を行うelectron spin resonance(ESR)法を用いた,フリーラジカルの検出において,クロラミンTでは,0.5%>1.0%>5.0%>10.0%>0%の順で,HClOやほかの酸化還元物質と反応して捕捉されるDMPO-Xの増加が認められた.一方,H<sub>2</sub>O<sub>2</sub>では,濃度依存的にOH・の増加が認められた.ラット腹直筋をクロラミンTに作用させたとき,タンパク質構造が破壊され,メチル基由来のカーボンセンターラジカル(C・)が認められたが,H<sub>2</sub>O<sub>2</sub>に作用させたとき,ESRシグナルの変化は認められなかった.ヘマトキシリン・エオジン染色において,ラット腹直筋は,クロラミンTおよびH<sub>2</sub>O<sub>2</sub>の濃度依存的に筋線維の萎縮,結合組織の融解および横紋構造の消失が認められた.ヒト歯根膜培養細胞を用いた24時間後の細胞毒性試験において,細胞生存率はクロラミンTでは,100%(0%),38.5%(0.5%),33.6%(1.0%),33.6%(5.0%),23.0%(10.0%)であったのに対し,H<sub>2</sub>O<sub>2</sub>では,100%(0%),14.9%(1.0%),14.7%(3.0%)であった.これらの結果から,クロラミンTは,H<sub>2</sub>O<sub>2</sub>と比較し,組織傷害性および細胞毒性が低い根管洗浄剤であり,高濃度ではタンパク質溶解を促進することが示唆された.

The aim of this study was to evaluate the function of Chloramine-T as a root canal irrigant. Varying concentrations of Chloramine-T and hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) were examined for tissue dissolution activity using rat rectus muscles, pH changes, free radical generation by means of electron spin resonance (ESR) spin trapping, tissue damaging activity using rat rectus muscles, and cytotoxicity in cultured human periodontal ligament cells. When 5.0% and 10.0% Chloramine-T or 3.0% H<sub>2</sub>O<sub>2</sub> were applied to rat rectus muscles for 1 hour, the weight of rat rectus muscles decreased. However, the weight of rat rectus muscles was not changed when 0.5% and 1.0% Chloramine-T or 1.0% H<sub>2</sub>O<sub>2</sub> were applied. The pH values of 0, 0.5, 1.0, 5.0 and 10.0% Chloramine-T were 6.22, 6.85, 7.83, 9.33 and 9.97, respectively. When these concentrations of Chloramine-T were applied to rat rectus muscles, each pH changed to 6.30, 7.07, 7.45, 7.52 and 7.51. Also, the pH values of 0, 1.0 and 3.0% H<sub>2</sub>O<sub>2</sub> were 6.22, 5.20 and 4.65, respectively. When H<sub>2</sub>O<sub>2</sub> was applied to rat rectus muscles, each pH changed to 6.54, 6.84 and 6.72. ESR spin trapping revealed that DMPO-X was detected from Chloramine-T in the order of 0.5%>1.0%>5.0%>10.0%>0%, and hydroxyl radical (OH・) was detected from H<sub>2</sub>O<sub>2</sub> in order of 3.0%>1.0%>0%. When Chloramine-T was applied to rat rectus muscles, the DMPO-X signals were diminished. However, the ESR signals showed no changes when H<sub>2</sub>O<sub>2</sub> was applied to the rat rectus muscles. Histological observation of Chloramine-T and H<sub>2</sub>O<sub>2</sub> exposed rat rectus muscles demonstrated atrophy of muscle fibers, dissolution of connective tissues and disappearance of striations in a does-dependent manner. H<sub>2</sub>O<sub>2</sub> caused stronger damages as compared with Chloramine-T. In the cytotoxicity experiments, the survival rate of human periodontal ligament cells decreased in a dose-dependent manner with Chloramine-T and H<sub>2</sub>O<sub>2</sub>. The survival rate was 100, 38.5, 33.6, 33.6 and 23.0%, when 0, 0.5, 1.0, 5.0 and 10.0%, respectively, of Chloramine-T was applied. The survival rate with 0, 1.0 and 3.0% H<sub>2</sub>O<sub>2</sub> was 100, 14.9 and 14.7%, respectively. These results suggested that Chloramine-T is a milder root canal irrigant than H<sub>2</sub>O<sub>2</sub>.

Journal

  • The Japanese Journal of Conservative Dentistry

    The Japanese Journal of Conservative Dentistry 53(2), 174-181, 2010

    The Japanese Society of Conservative Dentistry

References:  31

Cited by:  1

Codes

  • NII Article ID (NAID)
    110007880723
  • NII NACSIS-CAT ID (NCID)
    AN00191201
  • Text Lang
    JPN
  • Article Type
    Journal Article
  • ISSN
    0387-2343
  • Data Source
    CJP  CJPref  NII-ELS  J-STAGE 
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