利用有限元素分析法探討前牙牙根柱之應力分怖

Stress Analysis of Post - Reinforced Maxillary Anterior Teeth

李惠娥(Huey-Er Lee) ； 王兆祥(Chau Hsiang Wang) ； 林隆益(Long-Yih Lin)

《The Kaohsiung Journal of Medical Sciences》 7卷10期 (1991/10) Pp. 518-525

https://doi.org/10.6452/KJMS.199110.0518

摘要

臨床上對於經過牙髓治療後的牙在製作最後修復體之前，常利用牙根柱來強化質。當牙冠受外力時，應力會經由根柱的傳導而分佈於質間。因此牙根柱的設計與質間應力分佈具有密切的關係。雖然近來有臨床報告指出牙根柱並非必要的。因而本研究以有限元素分析法探討上顎正中門牙根柱製作的有無及用不同機械性質的牙根柱材料（包括：鎳鉻合金，鑄造金合金及複合樹脂）作贋復後，其受力時質應力分佈情形。其結果顯示1)有製作牙根柱較沒有製作者有較均勻的應力分析。(2)不同材料的牙根柱在各施力情況，有相似的應力分怖型態。(3)牙根柱的材料彈性係數愈大，分佈於牙根柱周圍質的應力也較大。(4)當施力時，除施力點外，最大的抗壓應力分佈於舌側靠近頸部處。

並列摘要

This study used plane stress analysis to survey the stress distribution of maxillary anterior teeth reinforced with posts of various materials, and maxillary anterior teeth without posts. Two-dimensional finite element models of the maxillary central incisor were subjected to a simulated biting force of 200N applied under various occlusal contact conditions.
The results of this study suggest that posts can transfer stress to the dentin and supporting alveolar bone, and that there is a more even stress distribution than in teeth without posts. Also, with post reinforcement the relative stress magnitudes and concentrations at the lingual surface of the post cervical area indicates that conservative enlargement of the root canal of the lingual surface is necessary. Finally, it seems that posts material with the same elastic modulous as the dentin may be the best choice.

並列關鍵字

post and core ； finite element stress analysis