Aguiar Fábio Afrânio de, Tiossi Rodrigo, Macedo Ana Paula, Mattos Maria da Gloria Chiarello de, Ribeiro Ricardo Faria, Rodrigues Renata Cristina Silveira
Department of Dental Materials and Prosthodontics, Dental School of Ribeirão Preto, University of São Paulo, São Paulo, Brazil.
J Craniofac Surg. 2012 Nov;23(7 Suppl 1):2019-23. doi: 10.1097/SCS.0b013e3182597c09.
The aim of this study was to compare the stresses resulting from cemented or screw-retained dental prostheses using universal cast to long abutment by the photoelastic method.
A photoelastic resin model was fabricated to simulate a segment of the mandibular arch with resin replicas of a first premolar and a second molar, and two 3.75 × 11-mm implants replacing the second premolar and the first molar. Vertical static loads were individually applied on the occlusal surface of the premolar and the molar (5 kgf) and simultaneously on both crowns (10 kgf).
Results found variable stress patterns around each implant and concentrated stresses in the individually loaded crowns. Force transfer characteristics of each situation and quantification of the isochromatic fringes were evaluated.
Within the limitations of this study and based on the results obtained for implant-supported prosthesis with internal hexagon connection/universal cast to long abutment, it could be concluded that single adjacent screw-retained prosthetic restorations lead to higher stresses around the implants when compared with cement-retained restorations.
本研究旨在通过光弹性方法比较使用通用铸造到长基台的粘结式或螺丝固位式牙修复体所产生的应力。
制作一个光弹性树脂模型，以模拟下颌牙弓的一部分，带有第一前磨牙和第二磨牙的树脂复制品，以及两颗替换第二前磨牙和第一磨牙的3.75×11毫米种植体。垂直静载荷分别施加在前磨牙和磨牙的咬合面上（5千克力），并同时施加在两个牙冠上（10千克力）。
结果发现每个种植体周围的应力模式各不相同，且在单独加载的牙冠中存在应力集中。评估了每种情况的力传递特性以及等色条纹的量化。
在本研究的局限性内，基于具有内六角连接/通用铸造到长基台的种植体支持修复体所获得的结果，可以得出结论，与粘结固位修复体相比，单个相邻的螺丝固位修复体在种植体周围会导致更高的应力。
