本文藉由建立下顎骨前端部位缺損重建之三維有限元素模型，探討不同重建方式對應力分佈的影響；當下顎骨受單側咬力負載時，以移植骨或鈦板重建於不同位置其分析結果的比較；在同樣邊界及材料性質條件下，施加雙側咬力相較於單側咬力對分析結果所產生的效應；以及使用雙鈦板取代單鈦板重建其鈦板應力分佈的差異。
分析結果發現移植骨圓角部位的應力遮蔽效應，為重建至底部案例較中間案例明顯；只以鈦板連結重建案例，對鈦板外表面及圓角部位的等效應力值，其應力值為重建至底部案例較中間案例小；相較單鈦板重建案例，使用雙鈦板重建對鈦板圓角部位的等效應力值約可減少40~50%。
綜合所有結果後，建議有加上移植骨的重建案例，選擇中間位置較佳，而只以單鈦板連結重建案例，則為底部位置較佳。對所有重建案例而言，鈦板的等效應力最大值幾乎全發生於靠近下顎骨缺損與移植骨相連處，可藉由增加鈦板斷面上寬度或厚度方向尺寸以減少應力值。

The purpose of this paper is to establish a three-dimensional finite element model of operation on mandibular defects in the anterior region and to discuss the influence of stress distribution between different reconstructed methods. We provide a comparison when the mandible is reconstructed at different positions by using the graft bone or titanium plates. In the same boundary conditions and material properties, the effect of applying bilateral bite forces is discussed as it is compared with the case of unilateral bite force. The stress distribution of the titanium plate is also investigated when the mandible is reconstructed by using two titanium plates.
The results show that the stress shielding effect at the fillet regions of graft bone in the bottom reconstructed cases is obvious as it is compared with the middle reconstructed cases. When the mandible is reconstructed with the titanium plate only, the equivalent stress for the anterior surface and fillet regions of titanium plate in the bottom reconstructed cases is smaller than in the middle reconstructed cases. Comparing with one titanium plate, the equivalent stress at the fillet regions of titanium plate can be reduced by 40~50% if the two titanium plates are used.
In conclusion, we suggest that the reconstructed case of operation by using the graft bone is designed at middle position. And if the mandible is reconstructed by using one titanium plate, we suggest that the titanium plate is designed at bottom position. In the all reconstructed cases of operation, the maximum equivalent stress for the titanium plate almost occurs near the connection of mandibular defects and graft bone. Stress can be reduced by enlarging cross-section size of the titanium plate along width or thickness direction.

Akiko, K., Nagasao, T., Kaneko, T., Miyamoto, J. and Nakajuma, T., “A comparative study of most suitable miniplate fixation for mandibular symphysis fracture using a finite element model”, Keio. J. Med., 55(1), pp.1-8, 2005.
Chu, L., Gussack, G. S. and Muller, T., “A treatment protocol for mandible fractures”, Journal of Trauma, Vol.36(1), pp.48-52, 1994.
Chen, J., Akyuz, U., Xu, L. and Pidaparti, R. M.V., “Stress analysis of the human temporomandibular joint”, Journal of Medical Engineering and Physics, Vol.20, pp.565-572, 1998.
Fernández, J. R., Gallas, M., Burguera, M. and Viaño, J. M., “A three-dimensional numerical simulation of mandible fracture reduction with screwed miniplates”, Journal of Biomechanics, Vol.36, pp.329-337, 2003.
Hart, R. T., Hennebel, V. V., Thongpreda, N., Van Buskirk, W. C. and Anderson, R. C., “Modeling the biomechanics of the mandible – a three-dimensional finite element study”, Journal of Biomechanics, Vol.25, pp.287-295, 1992.
Inou, N., Iioka, Y., Fujiwara, H. and Maki,K., “Functional Adaptation of Mandibular Bone”, in the book: Computational biomechanics, edit by: Hayashi, K., Ishikawa, H., Springer, Tokyo, 1996.
Knoll, W. D., Gaida, A. and Maurer, P., “Analysis of mechanical stress in reconstruction plates for bridging mandibular angle defects”, Journal of Cranio-Maxillofacial Surgery, Vol.34, pp.201-209, 2006.
Osborn, J. W. and Baragar, F. A., ”Predicted pattern of human muscle activity during clenching derived form a computer assisted model : symmetric vertical bite forces”, Journal of Biomechanics, Vol.18, pp.559-612, 1985.
Reina, J. M., Garc1’a-Aznar, J. M., Domi’nguez, J. and Doblare’, M., “Numerical estimation of bone density and elastic constants distribution in a human mandible”, Journal of Biomechanics, Vol.40, pp.828-836, 2006.
Riley, W. F., Sturges, L. D. and Morris, D. H., “Mechanics of Materials”, Eurasia Book Co., Taipei, pp.276-233, 2006.
Singare, S., Dichen, L. and Sanhu, H., “Fabrication of customised maxillo-facial prosthesis using computer-aided design and rapid prototyping techniques”, Journal of Rapid Prototyping, Vol.12, pp. 206-213, 2006.
Zhan, L., Yubo, F. and Yingli, Q., “Comparative evaluation on three-dimensional finite element models of the temporomandibular joint”, Journal of Clinical Biomechanics, Vol.23, pp. S53-S58, 2008.
林慧菁，下顎骨之三維有限元素模型建立與力學分析 Three-Dimensional Finite Element Modeling and Stress Analysis of Mandible， 國立成功大學機械工程學系碩士論文，台南市，民國九十一年。
梁文雄，Grant’s 解剖學，合記圖書出版社，臺北市，641-647頁，民國七十九年。
陳昱先、陳伊呈、歐令奮、顏榮信、唐友文，以游離血管莖骨皮瓣重建下顎骨廣泛缺損之經驗The Experience of Oromandibular Reconstruction Using Vascularized Bone Composite Free Flaps，中華重建整形外科醫誌，6卷，3期，199-209頁，民國八十六年。
陳冠瑜、黃欀基、趙守一、蔡樂霖、顏榮信、關寶祥，巨大下顎造釉細胞瘤切除後以游離腓骨皮瓣重建 Resection of A Huge Mandibular Ameloblastoma and Reconstruction with A Free Fibula Osteocutaneous Flap-Case Report, Chin J. Oral Maxillofac Surg., pp.58-73, 民國九十四年。
黃清皓，下顎骨重建金屬板用於下顎骨缺損之初期重建 Primary Reconstruction of the Mandible Using Mandibular Reconstruction Plate，中耳醫誌，35-38頁，臺北市，民國八十三年。
劉紹東、黃怡仁、黃友和、何宛怡、劉燦勳、蕭廷鑫、王紹娟合譯，醫用解剖學 Clinically Oriented Anatomy，力大圖書有限公司，16-27頁，臺北市，民國九十二年。
鄭凱元，重建下顎骨髁頸破壞之三維有限元素模型建立與力學分析 Three-Dimensional Finite Element Modeling and Stress Analysis of Reconstruct Mandible Condylar Neck Fractures，國立成功大學機械工程學系碩士論文，台南市，民國九十七年。
謝豐祺，缺損下顎骨重建手術之有限元素分析 Finite Element Analysis of Reconstructed Defect Mandible，國立成功大學機械工程學系碩士論文，台南市，民國九十八年。