Hobkirk J A, Havthoulas T K
Department of Prosthetic Dentistry, Eastman Dental Institute, University of London, United Kingdom.
J Prosthet Dent. 1998 Aug;80(2):169-74. doi: 10.1016/s0022-3913(98)70106-4.
Forces may arise in association with the use of implant stabilized mandibular fixed partial dentures as a result of functional jaw deformation, yet the phenomenon has received little attention and is rarely included as a variable when investigating implant biomechanics.
This in vitro investigation tested the hypothesis that functional mandibular deformation influences force distribution in the jaw/implant/superstructure complex.
Six Brånemark implants were mounted in an acrylic resin replica of an edentulous human mandible. Applied forces were measured with 4-element resistance strain gauges mounted on each of 6 standard titanium abutments. The mandible was supported either on its lower border or suspended in a frame that simulated the natural situation. A cast gold superstructure was a mounted on varying combinations of implants, loaded occlusally in different locations, and the resultant forces at each supporting transmucosal abutment measured.
The suspended ("natural") support configuration was associated with considerable differences in patterns of force transmission as compared with bench support. Loads were more widely spread, and large extrusion forces were detected, particularly where several implants were connected.
Functional mandibular deformation is a significant factor in the design of mandibular implant stabilized prostheses, and calls into doubt the value of modeling techniques that do not allow for this phenomenon.
由于功能性颌骨变形，在使用种植体支持的下颌固定局部义齿时可能会产生力，但这种现象很少受到关注，并且在研究种植体生物力学时很少被作为一个变量考虑在内。
本体外研究验证了功能性下颌变形会影响颌骨/种植体/上部结构复合体中力分布的假设。
在无牙颌人类下颌骨的丙烯酸树脂复制模型上植入6枚布伦马克种植体。通过安装在6个标准钛基台上的四元件电阻应变仪测量施加的力。下颌骨要么在下缘得到支撑，要么悬挂在模拟自然状态的框架中。铸造金上部结构安装在不同组合的种植体上，在不同位置进行咬合加载，并测量每个支持性穿黏膜基台上的合力。
与台架支撑相比，悬挂式（“自然”）支撑结构在力传递模式上存在显著差异。载荷分布更广泛，并且检测到较大的挤压合力，尤其是在连接多个种植体的地方。
功能性下颌变形是下颌种植体支持修复体设计中的一个重要因素，这使得不考虑这种现象的建模技术的价值受到质疑。
