中文摘要：

目的探讨季铵盐单体改性后牙本质粘接剂对变形链球菌生长、黏附的影响。方法将季铵盐单体[甲基丙烯酰氧乙基-正十六烷基-二甲基氯化铵（methacryloxylethyl cetyl dimethyl ammonium chloride，DMAE.CB）]加入二甲基丙烯酸酯基牙本质粘接剂作为改性组，以二甲基丙烯酸酯基牙本质粘接剂作为阴性对照组，两组分别制作39个试件。采用接触抑菌实验和黏附实验，比较无处理、老化处理和唾液处理后两组粘接剂表面变形链球菌的生长和黏附情况；检测两组粘接剂浸提液中变形链球菌的细菌倍增时间，评价浸提液的抑菌作用。结果无处理时改性组变形链球菌菌落数的中位数（四分位数间距）为2.80（1.50）×10^6CFU，显著低于阴性对照组[2.60（0.90）×10^8CFU，P〈0.01]，变形链球菌的生长抑制率为99％；改性组黏附细菌所制悬液的吸光度A600值（0.332±0.063）显著低于阴性对照组（0.434±0.093，P=0.021）。老化处理后改性组黏附细菌所制悬液的A600值（0.372±0.062）显著低于阴性对照组（0.455±0.066，P=0.022），变形链球菌的生长抑制率为99％；唾液处理后改性组黏附细菌所制悬液的A600值（0.299±0.061）显著低于阴性对照组（0.370±0.068，P=0.045），变形链球菌的生长抑制率为90％。改性组浸提液的细菌倍增时间为（130.5±8.4）min，与阴性对照组[（126.4±7.0）min]相比，差异无统计学意义（P=0.298）。结论DMAE-CB改性的牙本质粘接剂固化后其表面变形链球菌的生长和黏附受到抑制。

英文摘要：

Objective To incorporate an antibacterial monomer, methacryloxylethyl cetyl dimethyl ammonium chloride（DMAE-CB）, into a dental adhesive, and to evaluate the antibacterial activity against Streptococcus mutans（Sm） of this DMAE-CB-incorporated adhesive after being cured. Methods DMAE-CB was incorporated into a dimethacrylates-based dental adhesive as experimental group. The adhesive without DMAE-CB served as a negative control. Thirty-nine specimens were fabricated for each group. The effects of the cured adhesives on the growth and adherence of Sm were evaluated with growth inhibition assay and spectrophotometry respectively. The influence of aging treatment and saliva treatment on the antibacterial efficiency of the modified adhesive was evaluated. Moreover, the bacterial growth of Sm in the eluents of two different adhesives was examined. Results Compared with negative control, the cured DMAE-CB- incorporated dental adhesive exhibited inhibitory effect on the growth and adherence of Sm. The inhibition rate was 99% and the absorbance value was （0.332±0.063） for experimental group, significantly lower than that of negative control（0.434±0.093, P = 0.021）. Moreover, after aging treatment the DMAE-CB-incorporated adhesive could still inhibit the growth and adherence of Sm; the inhibition rate was 99%, and the absorbance value of experimental group was （0.372±0.062）, significantly lower than that of negative control（0.455±0.066, P=0.022）. After saliva treatment the DMAE-CB-incorporated adhesive could still inhibit the growth and adherence of Sm; the inhibition rate was 90%, and the absorbance value of experimental group was （0.299±0.061）, signifieantly lower than that of negative eontrol（0.370±0.068, P=0.045）. However, the eluent of DMAE-CB-incorporated adhesive didn＇t show inhibitory effect on the growth of Sm when compared with negative control, and the antibacterial effect and the doubling time of experimental group[（130.5±8.4） min]had no statistical difference than neg