Ryou Heonjune, Romberg Elaine, Pashley David H, Tay Franklin R, Arola Dwayne
Department of Mechanical Engineering, University of Maryland Baltimore County, Baltimore, MD, USA.
Department of Endodontics, Prosthodontics and Operative Dentistry, Dental School, University of Maryland, Baltimore, MD, USA.
J Mech Behav Biomed Mater. 2015 Feb;42:229-42. doi: 10.1016/j.jmbbm.2014.11.021. Epub 2014 Nov 29.
An experimental evaluation of human coronal dentin was performed using nanoscopic dynamic mechanical analysis (nanoDMA). The primary objectives were to quantify any unique changes in mechanical behavior of intertubular and peritubular dentin with age, and to evaluate the microstructure and mechanical behavior of the mineral deposited within the lumens. Specimens of coronal dentin were evaluated by nanoDMA using single indents and in scanning mode via scanning probe microscopy. Results showed that there were no significant differences in the storage modulus or complex modulus between the two age groups (18-25 versus 54-83 yrs) for either the intertubular or peritubular tissue. However, there were significant differences in the dampening behavior between the young and old dentin, as represented in the loss modulus and tanδ responses. For both the intertubular and peritubular components, the capacity for dampening was significantly lower in the old group. Scanning based nanoDMA showed that the tubules of old dentin exhibit a gradient in elastic behavior, with decrease in elastic modulus from the cuff to the center of tubules filled with newly deposited mineral.
使用纳米动态力学分析（nanoDMA）对人类牙冠部牙本质进行了实验评估。主要目的是量化管间牙本质和管周牙本质的力学行为随年龄的任何独特变化，并评估管腔内沉积矿物质的微观结构和力学行为。通过nanoDMA使用单压痕并通过扫描探针显微镜在扫描模式下对牙冠部牙本质标本进行评估。结果表明，对于管间组织或管周组织，两个年龄组（18 - 25岁与54 - 83岁）之间的储能模量或复数模量没有显著差异。然而，年轻牙本质和老年牙本质之间在阻尼行为上存在显著差异，如损耗模量和tanδ响应所示。对于管间和管周成分，老年组的阻尼能力显著较低。基于扫描的nanoDMA表明，老年牙本质的小管在弹性行为上呈现梯度变化，从充满新沉积矿物质的小管袖口到小管中心，弹性模量降低。
