4种窝沟封闭剂微渗漏及抗压强度的比较实验

Comparative study on microleakage and compressive strength of four fissure sealants

目的:比较4种窝沟封闭剂的微渗漏及抗压强度,为临床选择使用提供实验室依据。方法:收集12～16周岁志愿者因正畸治疗需要而新鲜拔除的前磨牙28个,并将其随机分为A、B、C、D 4组(n=7),分别用Helioseal F、VOCO Fissurit F、AscentTM和ClinproTM封闭牙合面及颊、舌侧窝沟;冷热循环100次后,分别从每组中各随机抽取5个用20 mg/L的亚甲蓝染色检查微渗漏;所余2个用扫描电镜观察窝沟封闭剂与牙体组织结合界面及两者之间的密合度。取4种窝沟封闭剂分别制作直径4 mm,厚4 mm的盘状标本各9个,置于生理盐水中37℃下浸泡。分别于浸泡后1 d、28 d、63 d后测定各标本的抗压强度(n=3)。结果:4种封闭剂之间微渗漏评分均无显著性差异(P>0.05);扫描电镜观察显示,VOCO Fissurit F与牙釉质完全结合在一起,并渗透到窝沟底部,Helioseal F、AscentTM、ClinproTM虽与釉质结合较紧密但窝沟底部的封闭剂中有气泡或断裂。4种封闭剂中AscentTM组3个时间点的抗压强度均高于其他3组(P<0.05),而另3组各时间点内两两相比均无统计学差异(P>0.05)。结论:VOCO Fissurit F的边缘密合性相对较好;AscentTM的抗压强度较高。

AIM： To evaluate the microleakage and compressive strength of 4 fissure sealants. METHODS ：28 caries -free premolars extracted for orthodontic reasons from 12 -16 years old volunteers were collected and randomly divid- ed into 4 groups（n =7）. Fissures were respectively sealed with Helioseal F, VOCO Fissurit F, Ascent^MT, and Clinpro^MT pit and fissure sealant. Then the teeth were thermocyclinged for 100 times. 5 teeth in each group were stained with 20 mg/L methylene blue for 24 hours, and then were sectioned for the evaluation of microleakage. The remaining 2 teeth in each group were used for the observation of marginal adaptability of fissure sealants with tooth interface by SEM. 9 disc - like specimens （with the thickness on 4nun diameter on 4mm） were prepared for each material and kept in normal saline at 37 %. The com- pressive strength of the specimens was examined 1 d, 28 d and 63 d afer saline treatment（ N = 3 ）. RESULTS ：There was no significant difference in the microleakage among the 4 sealants, VOCO Fissurit F fully penetrated into the bottom of the fis- sure and fully integrated with enamel observed by SEM. The interface between Helioseal F, Ascent^MT or Clinpro^MT sealants and enamel was close. Compressive strength value of Ascent^MT was significantly higher than that of other 3 sealants at all measurement days, but air bubble and crack were found. CONCLUSION：VOCO Fissurit F has excellent marginal adapta- tion. Ascent^MT has strong compressive strength.