The Effect of antimicrobial agent to artificial biofilm formed by periodontopathic bacteria

口腔生物膜是由多种微生物组成的。导致生物膜内组成变化的病原微生物的增加可引起龋齿和牙周病。在慢性牙周炎病变中，经常观察到牙龈卟啉单胞菌、齿垢密螺旋体和嗜酸坦纳氏菌的比例增加。本研究的目的是分析生物膜形成的机制，评价抗菌药物的抗生物膜效果，以建立一个有效的牙周治疗模式，利用抗菌药物。在评价对牙龈卟啉单胞菌的杀菌效果时，聚维酮碘显示出比氯己定更高的杀菌效果。因此，我们开发了一种模型，使用带有细胞培养插入物的24孔板定量评价聚维酮碘对生物膜形成的影响。将牙周致病菌接种于胰酪胨大豆肉汤中的碳酸氢钠膜上。然后加入各种浓度的聚维酮碘。浓度为2%或更高的聚维酮碘漱口液对牙龈卟啉单胞菌生物膜的杀菌效果比对照组提高了1000倍。当使用浓度为1%或更高的聚维酮碘时，观察到F nucleatum对生物膜的类似效果。

Oral biofilm is composed of many different microorganisms. An increase in pathogenic microorganisms which results in change of composition within the biofilm can cause dental caries and periodontal disease. In chronic periodontitis lesions, an increase in proportions of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia is frequently observed. The purpose of this study is to analyze the mechanism involved in biofilm formation, and evaluate anti-biofilm effects of antimicrobial agents in order to establish an effective periodontal treatment modality utilizing antimicrobial agents. Povidone-iodine showed higher bactericidal effects than chlorhexidine when effect for planktonic P. gingivalis was evaluated. Therefore we developed a model to quantitatively evaluate the effect of povidone-iodine on biofilm formation using a 24-well plate with cell culture inserts. The periodontopathic bacteria were inoculated on plycarbonate membrane in trypticase soy broth. Various concentrations of povidon-iodine were then added. The povidon-iodine gargle with concentrations of 2% or more showed 1, 000-fold increase in bactericidal effect on biofilm by P gingivalis compared with the control. A similar effect was observed on biofilm by F nucleatum, when the povidon-iodine was used with concentrations of 1% or more.