Objective To evaluate the effect of an 8％ arginine-CaCO3 containing desensitizing polishing paste on bonding strength of two self-etching adhesives to dentin.Methods Thirty-six intact human premolars extracted for orthodontic reasons were collected within 1 month after extraction and randomly assigned into three groups using a table of random numbers (n =12): specimens without any treatment served as control.In the polishing powder group specimens were polished with a slurry of pumice,and in the desensitizing polishing paste group dentin surfaces of the sample teeth were treated with 8％ arginine-CaCO3 containing desensitizing polishing paste.Then each group was divided into two sub-groups using a table of random numbers in order to evaluate the bonding strength of two self-etching adhesive agents (G-Bond,GC; Fl-Bond Ⅱ,Shofu).Microtensile bond strength test was conducted immediately and after 5000 thermocycling (n =15).Scanning electron microscope (SEM) was used to evaluate the occluding effect of the desensitizing polishing paste.Results In the prethermocycling stage,there were no significant differences in Fl-Bond Ⅱ bonding strength among the three groups [control: (30.34 ± 5.42) MPa,polishing powder group: (29.72 ± 5.16) MPa,desensitizing polishing paste group: (31.53 ± 4.86) MPa] (P ＞ 0.05).However there were significant differences among the three groups in G-Bond bonding strength [control: (38.19 ±4.42) MPa,polishing powder group: (36.47 ± 4.72) MPa,desensitizing polishing paste group: (46.88 ±7.83) MPa] (P ＜0.05).After thermocycling precess,there were no significant differences in bonding strenght among the three groups in both G-Bond groups and Fl-Bond Ⅱ groups.SEM observation showed that the desensitizing polishing paste could occlude open dentinal tubules effectively,and the application of self-etching adhesives could re-open the dentinal tubular orifices.An even layer can be seen on the dentin surface treated with self-etching adhesive containing functional monomers.Conclusions The 8％ arginine-CaCO3 containing desensitizing polishing paste could effectively occlude dentinal tubules,thus may have potential benefits in preventing post-operative sensitivity.Additionally,it had no adverse effect on bonding strength of self-etching adhesives to dentin.%目的 研究含8％精氨酸-碳酸钙的脱敏抛光膏对两种自酸蚀粘接剂粘接强度的影响,以期为临床提供参考.方法 将36颗离体前磨牙垂直于牙体长轴完全去除(牙合)面牙釉质,采用随机数字表法随机分为3组(每组12颗):空白对照组不进行处理,抛光粉组用浮石粉抛光牙本质面,脱敏抛光膏组用含8％精氨酸-碳酸钙的脱敏抛光膏抛光牙本质面.每组样本牙各采用随机数字表法随机分为两个亚组(每亚组6颗),分别使用两种自酸蚀粘接剂(A:G-Bond,含功能性单体；B:Fl-BondⅡ)进行粘接以及树脂修复.光照固化后将样本牙置于37℃双蒸水中24 h.冷热循环前及经5000次冷热循环后(每亚组冷热循环前后各制备15个试件),分别检测拉力峰值,计算粘接强度,并进行双因素方差分析.扫描电镜评价各组牙本质小管的封闭情况,并观察自酸蚀粘接剂处理后的牙本质面.结果 对于粘接剂A,冷热循环前脱敏抛光膏组粘接强度[(46.88±7.83) MPa]与空白对照组[(38.19 ±4.42) MPa]、抛光粉组[(36.47±4.72) MPa]的差异均有统计学意义(P＜0.05)；冷热循环后脱敏抛光膏组粘接强度[(32.02±8.77) MPa]与空白对照组[(34.38±6.39) MPa]、抛光粉组[(32.22±5.25)MPa]的差异均无统计学意义(P＞0.05).对于粘接剂B,无论冷热循环前还是冷热循环后脱敏抛光膏组粘接强度[分别为(31.53±4.86)和(24.25±3.67) MPa]与空白对照组[分别为(30.34±5.42)和(25.63±5.93) MPa]、抛光粉组[分别为(29.72±5.16)和(26.72±6.17) MPa]的差异均无统计学意义(P＞0.05).扫描电镜下可见经脱敏抛光膏处理后,牙本质小管口被有效封闭.脱敏抛光膏联合自酸蚀粘接剂处理后牙本质小管口可重新打开,使用粘接剂A的管间牙本质表面可见均匀分布的絮状沉积物.结论 含8％精氨酸-碳酸钙的脱敏抛光膏与自酸蚀粘接剂联合应用时,对粘接强度无不利影响,可在临床操作中联合应用.
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