不同玷污层对4种树脂粘接系统粘接强度及粘接耐久性的影响

Effect of different smear layers on the bonding performance and durability of four adhesive systems

背景:当用旋转式或手动器械处理牙表面时,在牙釉质和牙本质上由切割和磨损产生的碎片形成了玷污层。玷污层是影响牙和修复材料之间粘接的重要因素,明确玷污层对不同种类粘接剂的影响对口腔医生的临床选择与正确使用具有重要的临床意义。目的:评价使用不同金刚砂车针预备的试件在人工唾液中存储24 h与100 d后,对4种粘接剂与牙本质粘接强度的影响。方法:获取离体人磨牙80颗,分别进行600号碳化硅砂纸(对照)、中细粒度金刚砂车针、标准粒度金刚砂车针、粗粒度金刚砂车针4种牙本质表面处理,每种处理20颗;每种处理方法内分4个亚组,分别以两步法自酸蚀粘接剂Optibond Versa(VSA组)、一步法自酸蚀粘接剂Optibond All in One(AIO组)、通用型粘接剂Single Bond Universal(SBU组)及全酸蚀粘接剂Bond5(GLU组)进行树脂粘接。粘接完成后,将试件置于人工唾液中37℃储存24 h及100 d,随后进行微拉伸强度测试,使用扫描电镜观察牙本质端断裂面,并对断裂模式进行分析。结果与结论:(1)储存24 h:使用两步法粘接剂或全酸蚀粘接剂的情况下,不同表面处理组间的粘接强度比较差异无显著性意义(P>0.05);使用一步法粘接剂或通用型粘接剂的情况下,仅粗粒度车针组粘接强度低于砂纸组(P<0.05)。使用砂纸或中细粒度车针的情况下,仅AIO组与VSA组粘接强度比较无差异;使用标准粒度车针的情况下,仅AIO组与VSA组、GLU组与SBU组粘接强度比较无差异(P>0.05);使用粗粒度车针的情况下,VSA组与AIO组、GLU组、SBU组粘接强度比较差异均有显著性意义(P<0.05),其余组间比较无差异(P>0.05);(2)储存100 d:使用两步法粘接剂或全酸蚀粘接剂的情况下,不同表面处理组间的粘接强度比较差异无显著性意义(P>0.05);使用一步法粘接剂的情况下,仅粗粒度车针组粘接强度低于砂纸组(P<0.05);使用通用型粘接剂的情况下,仅标准粒度车针组、粗粒度车针组粘接强度低于砂纸组(P<0.05)。使用砂纸或中细粒度车针的情况下,仅VSA组与SBU组粘接强度无差异(P>0.05);使用标准粒度车针的情况下,仅SBU组与VSA组、GLU组与SBU组、GLU组与VSA组粘接强度无差异(P>0.05);使用粗粒度车针的情况下,仅VSA组与AIO组粘接强度无差异(P>0.05);(3)仅在使用两步法粘接剂的情况下,不同表面处理组100 d后的粘接强度与24 h比较差异有显著性意义(P<0.05);(4)与浸泡24 h相比,VSA组、SBU组、GLU组浸泡100 d后的粘接界面断裂和混合断裂比例略有增加,其中VSA组变化最大;与其他组比较,GLU组浸泡24 h与100 d的粘接界面断裂和混合断裂模式比例均超过50%;(5)结果表明,使用不同粒度车针预备产生了不同的玷污层,对一步法自酸蚀粘接剂粘接强度产生了显著影响,对两步法自酸蚀粘接剂和全酸蚀粘接剂未产生显著影响;存储时间对不同粘接剂产生了显著影响。

BACKGROUND: When the tooth surface is treated with a rotary or manual instrument, a smudge layer is formed on the enamel and dentin by debris generated by cutting and abrasion. The bonding interf ace between the adhesive and the dentin is considered as a weak part in the direct repair process. To clarify the effect of smear layer on different kinds of adhesive is significantly important for den tists to select and correctly use the adhesive in clinical treatment. OBJECTIVE: To evaluate the effect of different diamond burs on the dentin bonding performance of four adhesive systems to dentin after 24 hours and 100 days of artificial saliva-storage. METHODS: Adhesive systems were:(1) VSA(Optibond Versa, Kerr);(2) AIO(Optibond All in One, Kerr);(3) SBU(Single bond Universal, 3 M);(4) GLU(Bond 5, Gluma,Heraeus). In present study, 80 extracted human molars were randomly divided into four groups and each group is divided into 4 subgroups. Dentin surfaces were prepared by:(1) 600-grit SiC-paper(control group);(2) super-fine diamond bur;(3) regular diamond bur;(4) coarse diamond bur. Bonding agent was applied according to each manufacturer’s instruction. After light-curing, dentin surfaces were built-up with resin composite(A2, CHARISMA, Heraeus). The micro-tensile bond strength was determined after 24 hours and 100 days of storage in artificial saliva at 37℃. The fractured surfaces on dentin side were observed by scanning electron microscope. RESULTS AND CONCLUSION:(1) Storage for 24 hours: there was no significant difference among groups under VSA and GLU. Under SBU and AIO, the bond strength in the coarse diamond bur group was significantly lower than that in the control group(P<0.05). Using 600-grit Si C-paper or regular diamond bur, the bond strength showed no significant difference only between AIO and VSA groups. Using regular diamond bur, the bond strength showed no significant difference in the VSA group compared with the AIO, GLU and SBU groups(P>0.05). Using coarse diamond bur, the bond strength in the VSA group had significant difference compared with the AIO, GLU and SBU groups(P<0.05), and other groups had no significant difference(P>0.05).(2) Storage for 100 days, there was no significant difference among groups under VSA and GLU. Under SBU, the bond strength in the coarse diamond bur group was significantly lower than that in the control group(P<0.05). Using 600-grit SiC-paper, the bond strength showed no significant difference only between VSA and SBU groups(P>0.05). Using regular diamond bur, the bond strength showed no significant difference in the GLU group compared with the SBU, and VSA groups(P>0.05). Using coarse diamond bur, the bond strength had no significant difference between VSA and AIO groups(P<0.05).(3) Using VSA, the bond strength in each group at 100 days showed significant difference compared with that at 24 hours(P<0.05).(4)Compared with immersed for 24 hours, the ratio of bond interface and combined crack in the VSA, SBU and GLU groups after immersed for 100 days was increased, especially the VSA group. Compar ed with the other groups, the ratio of bond interface and combined crack in the GLU group after immersed for 24 hours and 100 days both increased by 50%.(5) These results indicate that preparation by different burs produces different smear layers, which has significant effect to self-etching adhesive system and has no significant effect to total-etching adhesive system. Storage time makes effect on different adhesives.