牙预备体用BisBlock^(TM)脱敏对水门汀剪切强度的影响

Effects of BisBlock^(TM) desensitizer used on basement tooth on shearing strength of cements.

目的:评价BisBlockTM脱敏剂对4种水门汀粘接强度的影响。方法:对48个离体牙片进行牙体预备,暴露牙本质,随机分4组:聚羧酸锌水门汀组、玻璃离子水门汀组、树脂加强型玻璃离子水门汀组、树脂水门汀组,每组12个样本。一半样本为实验组,涂用BisBlockTM脱敏剂;对照组不涂脱敏剂。用水门汀粘固镍铬合金铸件于牙本质表面。剪切实验后记录剪切强度及离断类型。采用t检验分析实验组和对照组间的剪切强度,采用Pearson's卡方检验分析离断面类型数据(α=0.05)。结果:BisBlockTM可提高树脂加强型玻璃离子水门汀和树脂水门汀的剪切强度,与树脂水门汀联合应用后剪切强度达到最大(13.04±2.76)MPa。结论:脱敏剂对水门汀粘接强度的影响与其产品成分有关;BisBlockTM脱敏剂可与实验中所有水门汀联合应用。

Objective：To evaluate the effects of BisBlock^TM desensitizer on shearing strength of 4 cements. Method：48 semi-teeth were operated to expose the dentin. The samples were divided to 4 groups at random： Zinc polycarboxylate cements group（ZPCC）,Glass ionomer cements group（GIC）,Resin-modified glass ionomer cements group（RMGIC）,Resin cements group（RC）. Each group concluded 12 specimens,half of them applied the BisBlock^TM desensitizer on the pretreated tooth,the others were control group with no desensitizer. Then cemented Ni-Cr alloy castings to the dentin with different cements. The shearing strength of all specimens were measured,and the failure type was recorded too. The shearing strength were analyzed with Independent Samples T Test between experiment group and control group,and the type of failure was analyzed with the Pearson＇s chi-square test（α=0.05）. Result：BisBlock^TM enhanced the shearing strength of RMGIC and RC,and the best shearing strength was found when BisBlock^TM combined with RC（13.04±2.76）MPa. Conclusion：The effect of BisBlock^TM desensitizer on bonding strength of different cements is related to the composition of desensitizer. BisBlock^TM could use in combination with all cements in this study.