摘要
背景:桩道及桩核预备过程中高速涡轮机产生的振动可破坏黏固剂与牙根及桩界面内的连续作用力,影响桩核的根方封闭效果。目的:观察不同时间预备桩道及桩核对纤维桩系统根方微渗漏的影响。方法:55颗离体下颌单根管前磨牙,采用逐步后退法预备根管。将样本分为即刻桩道预备组,2d后桩道预备组,1周后桩道预备组,阳性对照组,阴性对照组。每个预备组又随机分成3个亚组,分别在黏固剂调合15,30,60min后进行桩核预备后,经染色及透明化处理。在体式显微镜下记录各亚组根方微渗漏得分。结果与结论:1周后桩道预备组根尖微渗漏值显著高于2d后预备组和即刻预备组,差异有显著性意义(P<0.05)。黏固剂调合15,30与60min后进行桩核预备的微渗漏差异无显著性意义(P>0.05)。提示即刻桩道预备对根尖封闭能起到良好的保护作用。针对纤维桩,同一种黏固剂完全固化后,不同桩核预备时机对其微渗漏无影响。
BACKGROUND： The vibration of high speed turbine handpiece during post space and post core preparation has an adverse effect on the continuous force of the bonding interfaces among the cement, dentin and post core, which influences the apical sealing effect of post core. OBJECTIVE： To investigate the effects of post space and post core preparation at different time on apical microleakage with fiber posts system. METHODS： Totally 55 extracted mandibular premolars each with single root canal were biomechanically prepared by using the step back technique. The samples were divided into five groups randomly： the immediate post space preparation group, 2 days after post space preparation group, 1 week after post space preparation group, a positive control group and a negative control group. Each group was averagely divided into three subgroups and they all were mixed for 15, 30 and 60 minutes on the cements, and then performed post core preparation. After that, all roots were dyed and transparentized. The dyeing scores of apical microleakage in each group were recorded under stereoscopic microscope observation. RESULTS AND CONCLUSION： The score of apical microleakage in 1 week after post space preparation group was obviously higher than that in 2 days after post space preparation group. There were significant differences between the two groups （P 〈 0.05）. No significant difference was shown for the microleakage of post core preparation after mixed for 15, 30 and 60 minutes on the cements （P 〉 0.05）. These findings suggest that the immediate post space preparation can play a good protective effect on apical sealing. In terms of fiber posts, there are not effects of post core preparation at different time on apical microleakage after the same kind of cement solidified completely.
出处
《中国组织工程研究》
CAS
CSCD
2012年第29期5366-5370,共5页
Chinese Journal of Tissue Engineering Research
