Sadighpour L, Rezaei S, Geramipanah F, Mohammadi M, Choubchian S
Assistant Professor, Dental Research Center, Tehran University of Medical Sciences, Tehran, Iran.
J Dent (Tehran). 2010 Summer;7(3):124-31. Epub 2010 Sep 30.
Contradictory results have been reported over microleakage studies of restorative materials and methods. Despite the number of publications on leakage there are few evidences comparing the different microleakage evaluation methods. The purpose of the present study was to compare the clearing technique and longitudinal sectioning in the evaluation of dye penetration along a glass fiber post.
Fifteen single-rooted human teeth were endontically prepared and obturated with gutta percha points and a resin based sealer (AH26). A glass fiber post (Glassix) was cemented into each post space with a dual polymerizing resin cement (Varilink II) and the composite core (Tetric Ceram) was fabricated. Specimens were immersed in Indian ink solution for 72 hours after completion of 1500 cycles of thermal cycling. Then demineralized, cleared and evaluated for the deepest length of dye penetration using a stereomicroscope. Specimens were then cut longitudinally and the length of penetration was measured again by the same instrument. The mean difference of the penetrated length was analyzed by two methods using the paired t test and an analysis of correlation (α = 0.05).
No significant difference was found in the mean microleakage measured by the two methods (P= 0.07). Significant correlation was found between them (P=0.0001, r= 0.9)
The clearing technique and longitudinal sectioning showed the same results in microleakage of Glassix post and composite core within the limitation of the present study.
关于修复材料和方法的微渗漏研究报告结果相互矛盾。尽管有大量关于渗漏的出版物,但比较不同微渗漏评估方法的证据却很少。本研究的目的是比较在评估玻璃纤维桩沿桩身染料渗透情况时的透明技术和纵切技术。
选取15颗单根人牙进行根管预备,并用牙胶尖和树脂基封闭剂(AH26)进行充填。用双固化树脂水门汀(Variolink II)将玻璃纤维桩(Glassix)粘固于每个桩道内,制作复合树脂核(Tetric Ceram)。在完成1500次热循环后,将试件浸泡在印度墨汁溶液中72小时。然后进行脱矿、透明处理,并使用体视显微镜评估染料渗透的最深长度。随后将试件纵切,并用同一仪器再次测量渗透长度。采用配对t检验和相关性分析两种方法分析渗透长度的平均差异(α = 0.05)。
两种方法测得的平均微渗漏无显著差异(P = 0.07)。两者之间存在显著相关性(P = 0.0001,r = 0.9)。
在本研究的局限性内,透明技术和纵切技术在Glassix桩和复合树脂核的微渗漏方面显示出相同的结果。