人工唾液浸泡对牙本质黏结强度的影响

Effect of artificial saliva storage on the bond strength of dentin bonding specimens

目的:评价人工唾液浸泡对牙本质黏结强度的影响。方法:30个中龋人离体磨牙,在龋检液监控下慢速手机去龋后,以洞底为准磨平周围健康牙本质。然后随机分成3组,分别应用Prime & Bond NT、Adper Prompt、Contax黏结剂处理,其上制作复合树脂冠。制备1mm×1mm的条形试件,每个牙取黏结界面为正常牙本质(ND)和龋损内层牙本质(CAD)的试件各6个。再随机分成3组,其中1组立即进行微拉伸黏结强度测试(作为对照组),另2组分别在人工唾液中浸泡3个月、6个月,然后进行微拉伸黏结强度测试。结果:唾液浸泡前3种黏结系统对龋损内层牙本质和正常牙本质的黏结强度均无显著差异(P>0.05),唾液浸泡3个月,3种黏结系统对正常牙本质的黏结强度与对照组相比无显著下降,与对照组相比差异不显著(P>0.05);而对龋损内层牙本质的黏结强度均明显下降,显著小于对照组和正常牙本质(P<0.05)。唾液浸泡6个月,3种黏结系统对龋损内层牙本质的黏结强度均低于3个月组(P<0.05),对正常牙本质的黏结强度CT仍与对照组无显著差异(P>0.05),而NT和AP则明显低于3个月组(P<0.05)。结论:随着唾液浸泡时间延长,牙本质黏结强度逐渐下降,2种牙本质之间,龋损内层牙本质黏结稳定性较差。

AIM：To evaluate the effect of artificial saliva storage on the bond strengths of dentin bonding specimens.METHODS：Thirty extracted human molars with coronal carious lesions extending into mid-dentin were ground down until the carious dentin no longer stained with caries detector.The flat surfaces were bonded with one of the three dentin bonding agents（Adper Prompt,Contax and Primev Bond NT）,and covered with resin composites（Chrisma A2）.Matchstick-shaped samples through the bond interfaces at normal dentin（ND） and within carious dentin（CAD） were sectioned.Matchstick-shaped samples were randomly divided into 3 groups,1 group were immediately subjected to micro-tensile bond strength testing（control group）,and the other two groups were immersed in artificial saliva for 3 and 6 months,and were then subjected to micro-tensile bond strength test.RESULTS：There was no significant difference in the initial bond strength of three adhesives to ND or CAD before saliva storage.Three or 6 months after artificial saliva storage,the bond strengnth of the adhesives to CAD was significantly decreased（P 0.05） and the effect was time-dependent.However,the bond strength to normal dentin only slightly decreased after artificial saliva storage for 3 months（P 0.05）.After 6 months,the bond strength to ND was significantly lower in NT and AP groups（P 0.05）.CONCLUSION：Saliva storage decreases the bond strength of the adhesives tested.The bonding of the adhesives to CAD seems to be less stable than the bonding to ND.