免冲洗酸蚀复合体窝沟封闭系统的实验研究

目的比较免冲洗酸蚀复合体窝沟封闭系统和传统磷酸酸蚀窝沟封闭系统在恒牙应用时的封闭和微渗漏情况。方法16颗新鲜拔除的第三磨牙分成4组。Ⅰ组应用免冲洗酸、粘接剂Prime & bond NT和复合体窝沟封闭系统，Ⅱ组采用磷酸和Resin树脂窝沟封闭系统，Ⅲ组采用磷酸和复合体窝沟封闭剂，Ⅳ组采用免冲洗酸、粘接剂Prime & bond NT和Resin树脂窝沟封闭剂。应用硝酸银浸染法和实体显微镜检查微渗漏情况，扫描电镜观察窝沟封闭情况。结果4组牙齿都存在微渗漏。Ⅰ、Ⅳ组微渗漏比率均高于Ⅱ组（ P<0.01）；Ⅰ组和Ⅳ组、Ⅱ组和Ⅲ组的微渗漏比率也有统计学差异（ P<0.01），Ⅰ组高于Ⅳ组，Ⅲ组高于Ⅱ组。扫描电镜观察发现采用磷酸酸蚀组可见树脂突，材料均匀；采用免冲洗酸蚀组基本上未见树脂突，材料之间裂隙大。多数样本的窝沟底部渗透较差。结论免冲洗酸蚀系统的微渗漏高于磷酸酸蚀系统，复合体封闭剂的微渗漏较高；磷酸酸蚀法有利于提高窝沟封闭剂的固位。

Experimental study of compomer sealant with non-rinse conditioner used on permanent molar

OBJECTIVE: To compare the microleakage of compomer sealant with non-rinse conditioner and resin sealant with phosphoric acid (35%) by dye test and scanning electron microscope (SEM) observation. METHODS: 16 extracted third permanent molars were divided into 4 groups: Group I, non-rinse conditioner (NRC) + Prime & Bond NT + Dyract seal; Group II, phosphoric acid (35%) + Concise sealant; Group III, phosphoric acid (35%) + Dyract seal; Group IV, NRC + Prime & Bond NT + Concise sealant. The teeth were then coated with nail polish, placed in a 50% AgNO3 dye for 18 hours, and sectioned with a diamond saw. SEM observation was performed to evaluate microleakage in the teeth. RESULTS: Silver nitrate penetration was found in each group. The percentage of microleakage in group I was higher than that in group II, and group IV was higher than that in group II (P < 0.01). The percentage of microleakage of resin sealant with phosphoric acid was lower than that in compomer sealant with NRC (P < 0.01). On SEM observation, resin tags and few gaps were found in groups with phosphoric acid. Some gaps and bubbles were found at the bottom of the fissures, particularly in the narrow fissures because of the failure of sealant penetration. CONCLUSION: Resin sealant used with phosphoric acid was better than compomer sealant with NRC on microleakage.