纤维桩核材料及预备时机对粘接界面密合性影响的实验研究

目的 研究不同桩核预备时机对FRC纤维桩核和预成石英纤维桩核与牙体组织粘接界面密合性的影响.方法 40颗人离体前磨牙按桩核预备时机和纤维桩材料分为A、B、C、D 4组(n=10)(A组:FRC纤维桩+即刻预备组;B组:FRC纤维桩+延迟预备组;C组:预成纤维桩+即刻预备组;D组:预成纤维桩+延迟预备组).使用扫描电镜(SEM)分别在纤维桩核冠完成后、冷热循环5000次后和循环加载24万次后,观察测量每组试件桩核与牙体组织粘接界面的裂隙宽度,并进行统计学分析.结果 试件经冷热循环后,B组的裂隙宽度小于D组,有统计学差异,其余各组无统计学差异.试件经循环加载后,A组的裂隙宽度小于C组,有统计学差异,B组裂隙宽度小于D组,有统计学差异,其余各组的裂隙宽度相近无统计学差异.结论 对于同一种纤维桩材料,不同桩核预备时机可以达到相近的边缘密合性.FRC纤维桩核冠的边缘密合性优于预成石英纤维桩核冠的边缘密合性.

Effect of timing of coronal preparation on sealing ability of post

Objective To examine the effect of timing of coronal preparation on sealing ability of post. Methods The samples included 40 recently extracted single-rooted premolars. The samples were then divided into four groups,based on the type of post (FRC or prefabricated post) and the timing of coronal preparation (immediate or delayed),group A: FRC fiber post + immediate coronal preparation, group B: FRC fiber post + delayed coronal preparation,group C:prefabricated post + immediate coronal preparation,group D:prefabricated post + delayed coronal preparation. All specimens underwent 5000 thermal cycles to simulate hot and cold temperature changes in the mouth. SEM was used to measure the width of micro-cracks on the interface between the post-core and the tooth in each specimen of the four groups. Results After thermal aging,the width of micro-cracks in group B was smaller than that in group D,and there was no significant difference between other groups. After cyclic loadings,the width of micro-cracks in group A was smaller than that in group C,group B smaller than group D,and there was no significant difference between other groups. Conclusion For the same fiber pile material,the time of preparation of different post and core can reach similar marginal sealability. The marginal sealability of the FRC fiber post core crown was better than that of the pre quartz fiber post core.