正常下颌第二前磨牙牙周膜应力分布及其耐受阈的研究

A research of periodontal stress distribution and pain threshold of the right sec-ond premolar on lower mandible

摘要: 本研究采用三维有限元法对正常下颌第二前磨牙牙周膜应力分布及其耐受阈进行了研究。结果显示:(1)当牙齿承受最大垂直力和侧向力时,牙周膜单元最大主应力(σ1)分布不均匀,最大值均在牙槽嵴顶并且大小相近,分别为4.99×10^-3和4.35×10^-3MPa。因此确定本模型的牙周膜单元应力耐受阈为4.35×10^-3MPa。(2)根尖区应力很小,对于保护根尖孔处的牙髓血管和神经具有重要意义。(3)力计测量的最大力不能反映牙周膜的最大潜力。

Abstract: The periodontal stress distribution and pain threshold of the right second prernolar on lower mandible were studied.The results showed:（1）When the maximal vertical and lateral forces are loaded,the periodontal stress isn’t evenly distributed and the maximal value of σ1（maximum principle stress）is 4.99 × 10^-3 MPa and 4.35×10^-3 MPa. The pain threshold of the periodontium in this model is 4.35×10^-3 MPa;（2）It is very important for protection of the pulp vessle and nerve because the value of σ1 over the periappical area is very small;and（3）The rnaximal vertical bite force measured by dynamometer doesn’t represent the poten-tiality of periodontium.