臺灣博碩士論文加值系統

根管治療後的牙齒常常使用牙根柱(post)強化對牙齒抗斷裂強度(fracture resistance)，其中牙齒殘存齒質多寡是影響齒質強度的主要因素。鄰接面齲齒(proximal caries)是導致牙齒需要進行根管治療的原因之一。因為鄰接面齲齒而進行治療的牙齒往往會在近心側(mesial side)或是遠心側(distal side)造成大範圍的齒質缺損，局部齒質缺損對牙齒影響的探討是較少的。本研究目的主要是利用電腦輔助分析方式，探討不同近心側齒質缺損牙齒裝置牙根柱時應力變化，以提供臨床診斷與治療參考之用。實驗以有限元素軟體(ANSYS)分析人類下顎第一小臼齒三維實體模型，模擬不同近心側齒質缺損(高度2 mm、1.5 mm、1.0 mm、0.5 mm、0 mm)受到不同方向咬合力時應力變化。咬合力設定為100 N且通過小臼齒頰側咬頭頂點，PV表示平行牙齒長軸的垂直咬合力、PB表示由頰側45度方向往舌側的側方咬合力、PL表示由舌側45度方向往頰側的側方咬合力、PM表示由近心45度方向往遠心側的側方咬合力、PD表示由遠心45度方向往近心側的側方咬合力。結果發現當受PV力時，牙根柱在殘缺齒質交角處應力會隨著齒質缺損越多而有明顯集中。而受到PB、PL力時牙齒近心端齒頸部會隨著齒質缺損一開始有應力下降現象，但隨著齒質缺損而不足1 mm後應力有明顯上升現象。本實驗得到結論：局部殘缺齒質在垂直力作用下會導致牙根柱與牙齒交角處應力集中現象，當近心端齒質缺損而不足1 mm時，頰、舌方向的咬合力會比近、遠心方向的咬合力影響更大，側方力對牙齒及牙根柱的影響比垂直力大。

Abstract
Some reports point out the weakness of endodontically treated teeth, that it would reinforce the teeth by use of posts. However, residual tooth structure has major influence on resistance of tooth fracture. Teeth with proximal caries often need endodontic treatment. In those teeth, there are no tooth structure in mesial or distal side. Study for those situation is rare. The purpose of this study was to analyze the stress of post and core for mandibular first premolar with different mesial proximal decay during normal masticatory load by finite element method (FEM). In this study, the three-dimensional finite element method was employed to analyze the stress difficult to calculate by traditional clinical observation or experimental approaches. Solid models of the mandibular first premolar with five height of mesial tooth structure (2 mm, 1.5 mm, 1.0 mm, 0.5 mm, 0 mm) and casting post was build up. Solid model was transferred to the mesh model in FE package(ANSYS) to process the stress analysis. Five different force all 100 N were applied on buccal cusp tip: (1)PV: vertical force along tooth axis; (2)PB: 45 degree force from buccal to lingual direction. ; (3)PL: 45 degree force from lingual to buccal direction. ; (4)PM: 45 degree force from mesial to distal direction. ; (5)PD: 45 degree force from distal to mesial direction. The results showed that there are stress concentration increase in contact area between tooth and post with mesial tooth structure decrease in PV force. We also found that the stress decreased with mesial tooth structure decrease in PB and PL. But when tooth structure not enough of 1 mm, the stress concentrate increase observably. The conclusions of this study were that stress will concentrate in the area between post and tooth structure in PV force. PB and PL have more influence than PM and PDwhen proximal tooth structure loss. Lateral force has more influence on post and tooth structure than vertical force.

中文摘要
英文摘要
誌謝
第一章 前言與研究背景．．．．．．．．．．．．．．．．．．1
第二章 文獻回顧．．．．．．．．．．．．．．．．．．．．．3
第一節 冠部齒質與牙齒強度．．．．．．．．．．．．3
第二節 牙根柱有限元素分析．．．．．．．．．．．．7
第三節 牙根柱與牙根斷裂 ．．．．．．．．．．．．．10
第四節 研究目的 ．．．．．．．．．．．．．．．．13
第三章 材料與方法．．．．．．．．．．．．．．．．．．．．14
第一節 蒐集下顎第一小臼齒 ．．．．．．．．．．．15
第二節 製作掃描牙齒用具 ．．．．．．．．．．．．16
第三節 牙齒根管治療及補綴物製作 ．．．．．．．．17
第四節 牙齒掃描 ．．．．．．．．．．．．．．．．18
第五節 黏貼電阻應變計 ．．．．．．．．．．．．．19
第六節 有限元素模型建立及模型收斂性 ．．．．20
第七節 模型有效性驗證 ．．．．．．．．．．．．．22
第八節 元素材料特性及邊界條件 ．．．．．．．．．23
第四章 結果 ．．．．．．．．．．．．．．．．．．．．．．24
第一節 有效性驗證結果 ．．．．．．．．．．．．．24
第二節 PV力於不同近心端齒質高度下之分析結果 ．．25
第三節 PB力於不同近心端齒質高度下之分析結果 ．．27
第四節 PL力於不同近心端齒質高度下之分析結果 ．．29
第五節 PM力於不同近心端齒質高度下之分析結果．．31
第六節 PD力於不同近心端齒質高度下之分析結果．．33
第五章 討論．．．．．．．．．．．．．．．．．．．．．．．36
第一節 有限元素分析法 ．．．．．．．．．．．．．36
第二節 牙周膜探討 ．．．．．．．．．．．．．．．39
第三節 黏著劑層探討 ．．．．．．．．．．．．．．41
第四節 邊界條件設定 ．．．．．．．．．．．．．．42
第五節 牙齒應力分布探討 ．．．．．．．．．．．．43
第六章 實驗結論與未來展望．．．．．．．．．．．．．．．．46
第一節 實驗結論 ．．．．．．．．．．．．．．．．46
第二節 未來展望 ．．．．．．．．．．．．．．．．47
參考文獻．．．．．．．．．．．．．．．．．．．．．．．．．48
表格．．．．．．．．．．．．．．．．．．．．．．．．．．．55
圖型．．．．．．．．．．．．．．．．．．．．．．．．．．．57
表 次
第三章 材料與方法
表3-1 實驗用下顎第一小臼齒資料．．．．．．．．．55
表3-2 牙冠修磨標準．．．．．．．．．．．．．．．55
表3-3 各模型元素及節點數．．．．．．．．．．．．55
表3-4 實驗所使用之材料性質．．．．．．．．．．．55
第四章 結果
表4-1 有效性驗證實驗數值．．．．．．．．．．．．56

圖 次
第三章 材料與方法
圖3-1 實驗流程圖．．．．．．．．．．．．．．．．57
圖3-2 實驗牙齒外型．．．．．．．．．．．．．．．58
圖3-3 掃描定位夾具．．．．．．．．．．．．．．．58
圖3-4 掃描定位夾具 (牙齒固定夾臂) ．．．．．．．58
圖3-5 夾具底座．．．．．．．．．．．．．．．．．59
圖3-6 定位針與定位軸．．．．．．．．．．．．．．59
圖3-7 3D光學掃描機 ．．．．．．．．．．．．．．59
圖3-8 掃描所得外型．．．．．．．．．．．．．．．60
圖3-9 驗證實驗裝置、施力裝置．．．．．．．．．．60
圖3-10 不同近心端齒質高度模型．．．．．．．．．．60
圖3-11 不同近心端牙柱心高度模型．．．．．．．．．61
圖3-12 牙周膜、皮質骨、齒槽骨模型．．．．．．．．61
圖3-13 有限元素模型．．．．．．．．．．．．．．．61
圖3-14 邊界條件．．．．．．．．．．．．．．．．．61
圖3-15 施力方向．．．．．．．．．．．．．．．．．62圖3-16 不同網格大小與應力值．．．．．．．．．．．62
第四章 結果
圖4-1 受垂直方向力PV牙根柱應力變化 ．．．．．．63
圖4-2 受垂直方向力PV牙根應力變化 ．．．．．．．65
圖4-3 受頰側方向力PB牙根柱應力變化 ．．．．．．66
圖4-4 受頰側方向力PB牙根應力變化 ．．．．．．．67
圖4-5 受舌側方向力PL牙根柱應力變化 ．．．．．．68
圖4-6 受舌側方向力PL牙根應力變化 ．．．．．．．69
圖4-7 受近心方向力PM牙根柱應力變化．．．．．．70
圖4-8 受近心方向力PM牙根應力變化．．．．．．．71
圖4-9 受遠心方向力PD牙根柱應力變化 ．．．．．．72
圖4-10 受遠心方向力PD牙根應力變化 ．．．．．．．73
圖4-11 受PV、PB、PL應力差異比較圖 ．．．．．．．74

參考文獻
1.Helfer AR, Melnick S, Schilder H. Determination of the mosisture content of vital and pulpless teeth. Journal of Oral Surgery 1972;34:661-70.
2.Lee BS, Hsieh TT, Chi DC, Lan WH, Lin CP. The role of organic tissue on the punch shear strength of human dentin. Journal of Dentistry 2004;32:101-7.
3.Trope M, Ray HL Jr. Resistance to fracture of endodontically treated roots. Oral Surgery, Oral Medicine, and Oral Pathology 1992;73:99-102.
4.Fernandes AS, Dessai GS. Factors affecting the fracture resistance of post-core reconstructed teeth: a review. International Journal of Prosthodontics 2001;14:355-63.
5.Huang HM, Wang WN, Chiu WT, Lin CT, Lee SY. Dynamic finite element analysis of the human maxillary incisor under impact loading in various directions. Journal of Endodontic 2005;31:723-7.
6.Carter JM, Sorensen SE, Johnson RR, Teitelbaum RL, Levine MS. Punch shear testing of extracted vital and endodontically trested teeth. Journal of Biomechanics 1983;16:841.
7.Roydhouse RH. Punch shear stress for dental purpose. Journal of Dental Research 1970;49:131.
8.Sheets CE. Dowel and core foundations. Journal of Prosthetic Dentistry 1970;23:58-65.
9.Perel ML, Muroff EI. Clinical criteria for post and core. Journal of Prosthetic Dentistry 1972;28:405-11.
10.Sapone J, Lorencki SF. An endodontic-prosthodontic approach to internal tooth reinforcements. Journal of Prosthetic Dentistry 1981;45:164-74.
11.Eshelman EG Jr, Sayegh FS. Dowel materials and root fracture. Journal of Prosthetic Dentistry. 1980;50:342-4.
12.Cooney JP, Caputo M, Trabert KC. Rentention and stress distribution of tapered-end endodontic posts. Journal of Prosthetic Dentistry 1986;55:540-6.
13.Ross IF. Fracture susceptibility of endodontically treated teeth. Journal of Endodontic 1980;6:560-5.
14.Lau VM. The reinforcement of endodontically treatment. Dental Clinic oF North America 1976;20:313-28
15.Trabert KC, Caputo AA, Abou-Rass M. Tooth fracture： a comparison of endodontic and restorative treatment. Journal of Endodontic 1987;4:341-5
16.Kantor ME, Pines MS. A comparative study of restorative techniques for pulpless teeth. Journal of Prosthetic Dentistry 1977;38:405-12.
17.Sorenson JA, Martinoff JT. Intracoronal reinforcement and coronal coverages：a study of endodontically treated teeth. Journal of Prosthetic Dentistry 1984:51:780-4.
18.Reeh ES, Douglas WH, Messer HH. Stiffness of endodontically-treated teeth related to restoration technique. Journal of Dental Research 1989;68:1540-4.
19.Trabert KC, Caput AA, Abou-Rass M.：Tooth fracture--a comparison of endodontic and restorative treatments. Journal of Endodontics 1987;4:341-5.
20.Sorensen JA. Preservation of tooth structure. Journal of The California Dental Association 1988;16:15-22.
21.Joseph J, Ramachandran G. Fracture resistance of dowel channel preparations with various dentin thickness. Federation of Operative Dentistry 1990;1:32-5
22.Sorensen JA, Engelman MJ. Ferrule design and fracture resistance of endodontically treated teeth. Journal of Prosthetic Dentistry 1990;63:529-36.
23.Peroz I, Blankenstein F, Lange KP, Naumann M. Restoring endodontically treated teeth with posts and cores--a review. Quintessence International 2005;36:737-46.
24.Libman WJ, Nicholls JI. Load fatigue of teeth restored with cast posts and cores and complete crowns. International Journal of Prosthodontics 1995;8:155-61
25.Isidor F, Brøndum K, Ravnholt G. The influence of post length and crown ferrule length on the resistance to cyclic loading of bovine teeth with prefabricated titanium posts. International Journal of Prosthodontics 1999;12:78-82.
26.Pereira JR, de Ornelas F, Conti PC, do Valle AL. Effect of a crown ferrule on the fracture resistance of endodontically treated teeth restored with prefabricated posts. Journal of Prosthetic Dentistry 2006;95:50-4.
27.Tan PL, Aquilino SA, Gratton DG. In vitro fracture resistance of endodontically treated central incisors with varying ferrule heights and configurations. Journal of Prosthetic Dentistry 2005;93:331-6.
28.Tjan AHL, Engelman MJ. Resistance to root fracture of dowel channels with various thickness of buccal dentin walls . Journal of Prosthetic Dentistry 1985;53:496-500.
29.Gegauff AG. Effect of crown lengthening and ferrule placement on static load failure of cemented cast post-cores and crowns. Journal of Prosthetic Dentistry 2000;84:169-79.
30.Naumann M, Preuss A, Rosentritt M. Effect of incomplete crown ferrules on load capacity of endodontically treated maxillary incisors restored with fiber posts, composite build-ups, and all-ceramic crowns: an in vitro evaluation after chewing simulation. Acta Odontologica Scandinavica 2006;64:31-6.
31.DeTolla DH, Andreana S, Patra A, Buhite R, Comella B. Therole of the finite element model on dental implants. Journal of Oral Implantology 2000;16:77-81.
32.Davy DT, Dilley GL, Krejci RF. Determination of stress patterns in root-filled teeth incorporating various dowel designs. Journal of Dental research 1981;60:1301-10.
33.Ko CC, Chu CS, Chung KH, Lee MC. Effects of posts on dentin stress distribution in pulpless teeth. Journal of Prosthetic Dentistry 1992;68:421-7.
34.Ho MH, Lee SY, Chen HH, Lee MC.：Three-dimensional finite element analysis of the effects of posts on stress distribution in dentin. Journal of Prosthetic Dentistry 1994;72:367-72.
35.Holmes DC, Diaz-Arnold AM, Leary JM. Influence of post dimension on stress distribution in dentin. Journal of Prosthetic Dentistry 1996;75:140-7.
36.林威克：下顎第一小臼齒不同根柱直徑導致牙根斷裂之應力分析－有限元素法。碩士論文，高雄醫學大學，2005
37.Ichim I, Kuzmanovic DV, Love RM. A finite element analysis of ferrule design on restoration resistance and distribution of stress within a root. International Endodontic Journal 2006;39:443-52.
38.Gher ME, Dunlap RM. Clinical survey of fracture teeth. Journal of American dental Association 1987;114:174-7.
39.Murgel CA, Walton RE. Vertical root fracture and dentin deformation in curved roots: the influence of spreader design. Endodontics & Dental Traumatology 1990;6:273-8.
40.Durney EC, Rosen H. Root fracture as a complication of post design and insertion: a laboratory study. Operative Dentistry 1977;2:90-6.
41.Llena-Puy MC, Forner-Navarro L, Barbero-Navarro I：Vertical root fracture in endodontically treated teeth: a review of 25 cases. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontics 2001;92:553-5.
42.Sirimai S, Riis DN, Morgano SM. An in vitro study of the fracture resistance and the incidence ofvertical root fracture of pulpless teeth restored with six post-and-coresystems. Journal of Prosthetic Dentistry 1999;81:262-9.
43.Fraga RC, Chaves BT, Mello GS, Siqueira JF Jr. Fracture resistance of endodontically treated roots after restoration. Journal of Oral Rehabilitation 1998;25:809-13.
44.Bex RT, Parker MW. Effectof dental bonded post-core preparations on resistance to vertical root fracture. Journal of Prosthetic Dentistry 1992;67:768-72.
45.Hayashi M, Takahashi Y, Imazato S, Ebisu S. Fracture resistance of pulpless teeth restored with post-cores and crowns. Dental Materials 2006;22:477-85.
46.Assif D, Bitenski A, Pilo R, Oren E. Effect of post design on resistance to fracture of endodontically treated teeth with complete crowns. Journal of Prosthetic Dentistry 1993;69:36-40.
47.王兆祥：懸臂式固定牙橋之應力研究。博士論文，高雄醫學大學，1996
48.Asundi A, Kishen A. A strain gauge and photoelastic analysis of in vivo strain and in vitro stress distribution in human dental supporting structures. Archives of Oral Biology 2000;45:543-50.
49.Andersen KL, Pedersen EH, Melsen B. Material parameters and stress profiles within the periodontal ligament. American Journal of Orthodontics and Dentofacial Orthopedics 1991;99:427-40.
50.Albuquerque Rde C, Polleto LT, Fontana RH, Cimini CA. Stress analysis of an upper central incisor restored with different posts. Journal of Oral Rehabilitation 2003;30:936-43.

51.Reinhardt RA, Krejci RF, Pao YC, Stannard JG. Dentin stresses in post-reconstructed teeth with diminishing bone support. Journal of Dental Research 1983;62:1002-8.
52.Goel VK, Khera SC, Ralston JL, Chang KH. Stresses at the dentinoenamel junction of human teeth－a finite element investigation. Journal of Prosthetic Dentistry 1991;66: 451-9.
53.Khera SC, Goel VK, Chen RC, Gurusami SA. A three-dimensional finite element model. Operative Dentistry 1988;13:128-37.
54.Larry JS. Applied finite element analysis. John Wiley & Sons, Inc. 1984
55.Steele JM. Applied finite element modeling. Marcel Dekker, Inc. 1989
56.Goel VK, Khera SC, Gurusami S, Chen RC. Effect of cavity depth on stresses in a restored tooth. The Journal of Prosthetic Dentistry 1992;67:174-83.
57.Lin CL, Chang CH, Ko CC. Multifactorial analysis of an MOD restored human premolar using auto-mesh finite element approach. Journal of Oral Rehabilitation 2001;28:576-85.
58.Chatri K, Kunimichi S. Stress of tooth and PDL structure created by bite force. The Bulletin of Tokyo Medical And Dental University 1993;40:217-32.
59.Rees JS. An investigation into the importance of the periodontal ligament and alveolar bone as supporting structures in finite element studies. Journal of Oral Rehabilitation 2001;28:425-32
60.Erik A, Peutzfeldt A, Sahafi A. Finite element analysis of stresses in endodontically treated, dowel-restored teeth. Journal of Prosthetic Dentistry 2005;94:321-9.
61.Yamashita J, Shiozawa I, Takakuda K, Miyairi H. Deformation of restoration and fracture of luting cement film. Journal of Dentistry 1998;26:459-66.
62.Jager ND, Pallav P, Feilzer AJ. The apparent increase of the Young''s modulus in thin cement layers. Dental Materials 2004;20:457-62.