A development of antiplaque composite resin by chemically binding Dextranase

制备的实验树脂为：Bis-GMA 55.3%, TEGDMA 27.6%，聚丙烯酸16.6%,BPO 0.5%。该树脂在60℃下聚合24 h，在100℃下聚合4 h。制备该树脂圆盘（直径10mm，厚度1mm），存放在0.1 m -磷酸钾缓冲液（pH6.0）中。通过以下步骤将葡聚糖酶与椎间盘结合。将1个圆盘和n -乙基-5-苯基异唑唑磺酸盐（40mg）在10ml 0.1 m -磷酸钾缓冲液（pH6.0）中，在4ºC下搅拌1 h。然后加入葡聚糖酶（40单位），在4 -氨基甲酸乙酯下搅拌24 h。在一个圆盘上发现0.11个单位的葡聚糖酶活性。研究了葡聚糖酶结合树脂对变形链球菌糖基转移酶的影响。制备了7种材料的标本：1。葡聚糖酶结合实验树脂，未处理实验树脂，Unifast, Fuji Ionomer TypeII, Photoclearfil Bright, Silux Plus, Palfique Estelite。测定了葡萄糖基转移酶合成的水不溶性葡聚糖在样品上的含量。葡聚糖酶结合树脂对水不溶性葡聚糖合成的抑制作用强于其他样品。葡萄糖基转移酶对葡聚糖结合树脂样品的不溶性葡聚糖形成的抑制率约为未处理树脂样品的30%。因此，我们检测了变形链球菌MT6R的粘附能力和该生物在葡聚糖酶结合的实验树脂上的葡聚糖产量。采用扫描电子显微镜进行检测。葡聚糖酶结合的实验树脂比未处理的实验树脂更能抑制变形链球菌的粘附。结果表明，该葡聚糖酶结合实验树脂具有抗斑块活性。

The experimental resin was prepared : Bis-GMA 55.3%, TEGDMA 27.6%, polyacrylic acid 16.6%, BPO 0.5%. This resin was polymerized for 24 h at 60ﾟC and 4 h at 100ﾟC. The discs of this resin(10mm in diameter and 1mm thickness)were prepared and stored in 0.1M-potassium phosphate buffer solution(pH6.0). Dextranase was bonded to the disc by the following procedure. One disc and N-ethyl-5-phenylisoxazolium3'-sulfonate(40mg)were stirred for 1 h at 4ﾟC in 10ml of 0.1M-potassium phosphate buffer(pH6.0). Dextranase(40units)were then added, and the reaction mixture stirred for 24 h at 4ﾟC. 0.11 units of dextranase activity was found on a disc.The effect of dextranase bound resin on the glucosyltransferase of Streptococcus mutans was investigated. Specimens of seven materials were prepared : 1. the dextranase bound experimental resin, the untreated experimental resin, Unifast, Fuji Ionomer TypeII, Photoclearfil Bright, Silux Plus, Palfique Estelite. Water insoluble glucan synthesizd by glucosyltransferase on the specimens were measured. The dextranase bound resin specimen inhibited water insoluble glucan synthesis more strongly than the another specimens. The percent inhibition of water insoluble glucan formation by glucosyltransferase on the dextranase bound resin specimen was about 30% of the untreated resin specimen.We thus examined the adherent ability of Streptococcus mutans MT6R and glucan production by this organism on the dextranase bound experimental resin. Scaning electron microscope was utilized to make this examination. The dextranase bound experimental resin inhibited the adherence of Streptococcus mutans more strongly than the untreated experimental resin.From this investigation it was concluded that this dextranase bound experimental resin have antiplaque activity.