Zarone Fernando, Sorrentino Roberto, Apicella Davide, Valentino Bartolomeo, Ferrari Marco, Aversa R, Apicella A
Second University of Naples, DISPAMA, Material Division, Aversa, Italy.
Dent Mater. 2006 Nov;22(11):1035-44. doi: 10.1016/j.dental.2005.11.034. Epub 2006 Jan 10.
The present study aimed at evaluating different restoring configurations of a crownless maxillary central incisor, in order to compare the biomechanical behavior of the restored tooth with that of a sound tooth.
A 3D FE model of a maxillary central incisor is presented. An arbitrary static force of 10 N was applied with an angulation of 125 degrees to the tooth longitudinal axis at level of the palatal surface of the crown. Different material configurations were tested: composite, syntered alumina, feldspathic ceramic endocrowns and glass post resorations with syntered alumina and feldspathic ceramic crown.
High modulus materials used for the restoration strongly alter the natural biomechanical behavior of the tooth. Critical areas of high stress concentration are the restoration-cement-dentin interface both in the root canal and on the buccal and lingual aspects of the tooth-restoration interface. Materials with mechanical properties underposable to that of dentin or enamel improve the biomechanical behavior of the restored tooth reducing the areas of high stress concentration.
The use of endocrown restorations present the advantage of reducing the interfaces of the restorative system. The choice of the restorative materials should be carefully evaluated. Materials with mechanical properties similar to those of sound teeth improve the reliability of the restoartive system.
本研究旨在评估无冠上颌中切牙的不同修复结构,以便比较修复后牙齿与健康牙齿的生物力学行为。
展示了上颌中切牙的三维有限元模型。在牙冠腭面水平,以与牙齿纵轴成125度角施加10 N的任意静态力。测试了不同的材料结构:复合材料、烧结氧化铝、长石质陶瓷内冠以及带有烧结氧化铝和长石质陶瓷冠的玻璃桩修复体。
用于修复的高模量材料强烈改变了牙齿的自然生物力学行为。高应力集中的关键区域是根管内以及牙齿修复界面的颊侧和舌侧的修复体 - 粘结剂 - 牙本质界面。机械性能低于牙本质或牙釉质的材料可改善修复后牙齿的生物力学行为,减少高应力集中区域。
使用内冠修复具有减少修复系统界面的优点。应仔细评估修复材料的选择。机械性能与健康牙齿相似的材料可提高修复系统的可靠性。