Rundegren J, Simonsson T, Petersson L, Hansson E
Department of Biology, Biosurface AB, Malmö, Sweden.
J Dent Res. 1992 Nov;71(11):1792-6. doi: 10.1177/00220345920710110501.
Glucan-containing plaque was formed by Streptococcus mutans adhering to saliva-coated glass slides in flow cells thermostated at 37 degrees C. The substrate was Brain Heart Infusion broth containing 1% sucrose and 10% sterile saliva. During the build-up of the plaque, which lasted for 29 h, the plaque was subjected to three two-minute exposures to either 0.1 mol/L sodium acetate buffer, pH 6.0, or the same buffer containing 6.4 mmol/L (0.2%) of the surface-active anti-plaque substance delmopinol hydro-chloride. The glass slides carrying the plaque were weighed, and plaques subjected to delmopinol treatment weighed only seven percent of the control plaques. The glass slides were then mounted in a beaker containing buffer, subjected to ultrasonication, and re-weighed. The delmopinol-treated plaques lost 59% of their wet weight upon sonication, while the controls lost only 19%. Control plaques having the same weight as delmopinol-treated plaques were not different from the control plaques grown for 29 h with regard to reduction of plaque weight after sonication. Transmission electron micrographs (TEM) showed a plaque dominated by globular or fibrillar matrix components in controls, while the delmopinol-treated plaque showed empty or unordered matrix areas between more densely packed cells. The TEM results were confirmed by scanning electron micrographs, which showed amorphous material associated with the bacterial cells in the control but not in the delmopinol-treated plaque. In conclusion, delmopinol reduced surface-associated glucan synthesis and lowered the cohesion of the plaque, indicating that glucan-containing plaque formed during repeated rinsings with delmopinol may be easier to remove by mechanical means than a non-treated plaque of this type.
变形链球菌在恒温37摄氏度的流动小室中粘附于涂有唾液的载玻片上，形成了含葡聚糖的菌斑。底物是含有1%蔗糖和10%无菌唾液的脑心浸液肉汤。在持续29小时的菌斑形成过程中，菌斑接受了三次两分钟的暴露处理，分别暴露于pH值为6.0的0.1摩尔/升醋酸钠缓冲液，或含有6.4毫摩尔/升（0.2%）表面活性抗菌斑物质盐酸地莫匹醇的相同缓冲液中。对载有菌斑的载玻片进行称重，经地莫匹醇处理的菌斑重量仅为对照菌斑的7%。然后将载玻片安装在装有缓冲液的烧杯中，进行超声处理，再称重。经地莫匹醇处理的菌斑在超声处理后失去了59%的湿重，而对照菌斑仅失去了19%。与经地莫匹醇处理的菌斑重量相同的对照菌斑，在超声处理后菌斑重量的减少方面与生长29小时的对照菌斑没有差异。透射电子显微镜（TEM）图像显示，对照菌斑中以球状或纤维状基质成分占主导，而经地莫匹醇处理的菌斑在更密集堆积的细胞之间显示出空洞或无序的基质区域。扫描电子显微镜图像证实了TEM结果，该图像显示对照菌斑中有与细菌细胞相关的无定形物质，而经地莫匹醇处理的菌斑中则没有。总之，地莫匹醇减少了表面相关葡聚糖的合成，降低了菌斑的凝聚力，这表明在用盐酸地莫匹醇反复冲洗过程中形成的含葡聚糖菌斑，可能比未处理的此类菌斑更容易通过机械手段去除。
