Menezes M S, Queiroz E C, Campos R E, Martins L R M, Soares C J
School of Dentistry of Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.
Int Endod J. 2008 Jun;41(6):476-84. doi: 10.1111/j.1365-2591.2008.01378.x. Epub 2008 Mar 16.
To test the hypothesis that the composition of endodontic sealer cements and the time elapsed between root filling and fibreglass post fixation interferes with adhesion to root canal dentine.
Sixty bovine incisor roots were divided into five groups (n = 12): CI, unfilled; SI, filled with a calcium hydroxide-based cement-Sealer 26, and immediate post fixation; S7, Sealer 26 and post fixation after 7 days; EI, filled with a zinc oxide and eugenol-based cement-Endofill and immediate fixation; and E7 Endofill and post fixation after 7 days. The posts were cemented with adhesive system and dual resin cement. Ten roots were cross-sectioned to obtain two 1-mm-thick discs for each cervical (TC), middle (TM) and apical (TA) third of the prepared root portion. The posts were submitted to a micropush-out test. The other two teeth were evaluated using scanning electron microscopy to analyse the bond interface. Data were analysed using anova, Tukey and Dunnett tests (P < 0.05).
Group EI was associated with a significant reduction in bond strength values irrespective of the root region; TC = 3.50 MPa (P = 0.0001); TM = 2.22 MPa (P = 0.0043) and TA = 1.45 MPa (P = 0.003). Region of canal had an influence on the values for the cement used in group E7, in which only the TA presented differences from the CI.
Endofill interfered negatively with the bond to root dentine along its full length and in the TA when post fixation was delayed for 7 days. Bond strength decreased from crown to apex in all groups.
验证以下假设，即根管封闭剂的成分以及根管充填与玻璃纤维桩固定之间的时间间隔会影响其与根管牙本质的黏附。
将60颗牛切牙根分为五组（n = 12）：CI组，未充填；SI组，用氢氧化钙类封闭剂Sealer 26充填并立即进行桩固定；S7组，用Sealer 26充填，7天后进行桩固定；EI组，用氧化锌丁香酚类封闭剂Endofill充填并立即固定；E7组，用Endofill充填，7天后进行桩固定。用粘结系统和双固化树脂水门汀粘结桩。将10颗牙根横切，为预备根管部分的每个颈段（TC）、中段（TM）和根尖段（TA）获取两个1毫米厚的切片。对桩进行微推出试验。使用扫描电子显微镜评估另外两颗牙齿，以分析粘结界面。数据采用方差分析、Tukey检验和Dunnett检验进行分析（P < 0.05）。
无论在哪个根段，EI组的粘结强度值均显著降低；颈段（TC）= 3.50兆帕（P = 0.0001）；中段（TM）= 2.22兆帕（P = 0.0043）；根尖段（TA）= 1.45兆帕（P = 0.003）。根管部位对E7组所用封闭剂的值有影响，其中只有根尖段与CI组存在差异。
当桩固定延迟7天时，Endofill会对整个根管长度以及根尖段与牙根牙本质的粘结产生负面影响。所有组的粘结强度从冠部到根尖均降低。
