Meijer H J, Starmans F J, Steen W H, Bosman F
Department of Oral-Maxillofacial Surgery, Prosthodontics and Special Dental Care, University of Utrecht, The Netherlands.
Arch Oral Biol. 1993 Jun;38(6):491-6. doi: 10.1016/0003-9969(93)90185-o.
The design of dental superstructures influences the loading on dental implants and the deformation of the anterior interforaminal bone in an edentulous mandible. This deformation causes stress in the bone around the implants and may lead to bone resorption and loss of the implant. The stress distribution around dental implants in an edentulous mandible was calculated by means of a three-dimensional, finite-element model of an entire lower jaw. This model was built from data obtained from slices of a single human mandible and was provided with two endosseous implants in the interforaminal region. The implants were either connected with a bar or remained solitary, and were loaded with a horizontal bite force of 10 N, a vertical bite force of 35 N, or an oblique bite force of 70 N. The most extreme principal stresses in the bone were always located around the neck of the implant. Stress around the implant was, therefore, not only caused by the local deformation of the bone due to movement of the implant and interface relative to the surrounding bone but also by the bending of the mandible. The most extreme principal stress was found with oblique bite forces. The highest maximum and lowest minimum principal stresses were 7.4 and -16.2 MPa in the model without the bar and 6.5 and -16.5 MPa in the model with the bar. When differences in the amount of bite force were eliminated, the vertical bite force resulted in the lowest stress.(ABSTRACT TRUNCATED AT 250 WORDS)
牙上部结构的设计会影响牙种植体上的负荷以及无牙下颌前孔间骨的变形。这种变形会在种植体周围的骨中产生应力，并可能导致骨吸收和种植体丧失。通过整个下颌骨的三维有限元模型计算无牙下颌中牙种植体周围的应力分布。该模型基于从单个人类下颌骨切片获得的数据构建，并在前孔间区域设置了两个骨内种植体。种植体要么通过杆连接，要么保持独立，并承受10 N的水平咬合力、35 N的垂直咬合力或70 N的斜向咬合力。骨中的最大主应力总是位于种植体颈部周围。因此，种植体周围的应力不仅由种植体和界面相对于周围骨的移动导致的骨局部变形引起，还由下颌骨的弯曲引起。斜向咬合力时发现最大主应力最大。在无杆模型中，最大主应力和最小主应力的最高值和最低值分别为7.4 MPa和 -16.2 MPa，在有杆模型中为6.5 MPa和 -16.5 MPa。当消除咬合力大小的差异时，垂直咬合力导致的应力最低。（摘要截短于250字）
