中文摘要：

目的：将季铵盐抗菌单体甲基丙烯酰氧乙基一正十六烷基一二甲基氯化铵（DMAE-CB）添加到窝沟封闭剂中获得改性封闭剂,评价改性封闭剂对细菌生长、黏附的影响。方法：将DMAE-CB添加到商品窝沟封闭剂Helioseal中获得DMAE-CB改性封闭剂作为实验组;未添加抗菌单体的Helioseal则作为阴性对照,具备氟释放功能的窝沟封闭剂Helioseal F作为阳性对照,采用接触抑菌实验和黏附实验评价改性封闭剂的固化表面对变异链球菌生长和黏附的影响;研究老化处理对改性材料表面抗菌性能的影响;检测材料浸提液的抗菌活性。结果：DMAE-CB改性封闭剂固化后表面可以抑制变异链球菌的生长和黏附,老化处理后改性材料表面仍表现出一定的抗菌活性。同阴性对照相比,改性材料浸提液对细菌生长没有显著影响（P〉0.05）。结论：DMAE-CB改性封闭剂固化后具备一定的抗菌活性,可以抑制变异链球菌的生长和黏附,老化处理后改性封闭剂材料仍表现出一定的抗菌活性,表现为接触性抑菌。

英文摘要：

AIM： To incorporate an antibacterial monomer,methacryloxylethyl cetyl dimethyl ammonium chloride（DMAE-CB）,into a pit and fissure sealant,and to evaluate the antibacterial activity of this DMAE-CB-incorporated sealant against Streptococcus mutans.METHODS： DMAE-CB was incorporated into a clinically used sealant,Helioseal.Helioseal without DMAE-CB served as a negative control.Helioseal F,containing a fluoride-releasing resin,was used as a positive control.The effects of the cured sealants on the growth and adherence of S.mutans were determined by film contact test and absorbance measurement,respectively.The influence of aging treatment on the antibacterial efficiency of the modified sealant was evaluated.Moreover,the bacterial growth in the eluents of three different sealants was investigated.RESULTS： The cured DMAE-CB-incorporated sealant exhibited inhibitory effect on the growth and adherence of S.mutans（P0.05）;whereas its eluent didn＇t show detectable antibacterial activity.Moreover,after aging treatment,the DMAE-CB-incorporated sealant could still inhibit the growth and adherence of S.mutans significantly（P0.05）.CONCLUSION： The DMAE-CB-incorporated sealant after polymerization showed a contact antibacterial effect against S.mutans,which could inhibit the bacterial growth and biofilm accumulation.The antibacterial activity could be maintained after aging process.