Department of Civil Engineering & Mechanics, University of Wisconsin-Milwaukee, WI 53211, USA.
Dent Mater. 2013 Aug;29(8):e161-7. doi: 10.1016/j.dental.2013.04.019. Epub 2013 Jun 2.
The objective of this research was to study the polymerization shrinkage in a dental composite using 3D digital image correlation (DIC).
Using 2 coupled cameras, digital images were taken of bar-shaped composite (Premise Universal Composite; Kerr) specimens before light curing and after for 10 min. Three-dimensional DIC was used to assess in-plane and out-of-plane deformations associated with polymerization shrinkage.
The results show the polymerization shrinkage to be highly variable with the peak values occurring 0.6-0.8mm away from the surface. Volumetric shrinkage began to significantly decrease at 3.2mm from the specimen surface and reached a minimum at 4mm within the composite. Approximately 25-30% of the strain registered at 5 min occurred after light-activation. Application of 3D DIC dental applications can be performed without the need for assumptions on the deformation field.
Understanding the local deformations and strain fields from the initial polymerization shrinkage can lead to a better understanding of the composite material and interaction with surrounding tooth structure, aiding in their further development and clinical prognosis.
本研究旨在使用 3D 数字图像相关（DIC）研究牙科复合材料的聚合收缩。
使用 2 个耦合相机，在光固化前和光固化后 10 分钟对条状复合材料（Kerr 公司的 Premise Universal Composite）样本拍摄数字图像。使用三维 DIC 评估与聚合收缩相关的面内和面外变形。
结果表明聚合收缩具有高度可变性，峰值出现在离表面 0.6-0.8mm 处。体积收缩从离样本表面 3.2mm 处开始显著减少，并在复合材料内 4mm 处达到最小值。大约 25-30%的应变在光激活后 5 分钟内记录。应用 3D DIC 牙科应用无需对变形场做出假设即可进行。
了解初始聚合收缩的局部变形和应变场，可以更好地理解复合材料及其与周围牙齿结构的相互作用，有助于进一步开发和临床预后。
