Jedrychowski J R, Bleier R G, Caputo A A
Section of Pediatric Dentistry, UCLA School of Dentistry, USA.
ASDC J Dent Child. 1998 Mar-Apr;65(2):111-5.
It is commonly accepted that stresses associated with polymerization shrinkage of composite restoratives can be reduced by utilization of an incremental filling procedure. A recent report using finite element analysis on a simple box preparation has shown that such a procedure actually produces higher stresses. The purpose of this investigation was to visualize the stresses generated by composite resin placed into photoelastic models of two surface preparations using different incremental techniques. Primary molar preparations were cast life-sized in a photoelastic material. Cavity walls were cleansed, primed and coated with unfilled resin. Incremental filling techniques of a hybrid composite resin were gingivo-occlusal, oblique, and facio-lingual. Comparisons were made with the bulk placement technique. The stresses developed within the model teeth were observed in the field of a circular polariscope under magnification. Generally few differences in shrinkage-induced stresses, were observed between the incremental filling techniques tested. The lowest shrinkage stresses were generated by the bulk placement technique.
人们普遍认为，通过采用分层填充技术可以降低与复合树脂修复体聚合收缩相关的应力。最近一份对简单盒状预备体进行有限元分析的报告表明，这种技术实际上会产生更高的应力。本研究的目的是观察使用不同分层技术将复合树脂填入两种洞形预备体的光弹性模型中所产生的应力。将第一恒磨牙预备体按实际尺寸浇铸在光弹性材料中。洞壁清洁、涂底漆并涂上未填充树脂。混合复合树脂的分层填充技术为龈合向、斜向和颊舌向。与整块充填技术进行比较。在圆偏光镜下放大观察模型牙内产生的应力。一般来说，在所测试的分层填充技术之间，观察到的收缩诱导应力差异不大。整块充填技术产生的收缩应力最低。
