林立德Lin, Li-Deh臺灣大學:臨床牙醫學研究所陳品翰Chen, Ping-HanPing-HanChen2010-05-262018-07-092010-05-262018-07-092009U0001-2907200914333700http://ntur.lib.ntu.edu.tw//handle/246246/184190實驗目的：施德丁類藥物主要是一種HMG-CoA還原酶競爭性抑制劑，目前廣泛地運用在治療高血脂症。最近經由研究證實，施德丁類藥物能夠誘導骨母細胞中骨型態蛋白-2(BMP-2)訊息核醣核酸的促進劑產生並且刺激骨頭生長。進一步地，已經有動物試驗報告指出施德丁類藥物對於促進骨頭生長有確實的效果。洛伐施德丁為施德丁類藥物分類中的一種，已經在動物試驗中測出有誘發骨頭生成的能力。本實驗之目的就是藉由骨組織型態學及生物力學測試來比較於表面塗覆洛伐施德丁的人工鈦合金牙根植體在植入狗脛骨後，其周圍骨頭反應與對照組之間是否有所不同。料與方法：在本實驗中，我們使用長十釐米、直徑四釐米的鈦六鋁四釩螺旋形人工植體進行測試，並將人工植體表面處理為粗糙面及平滑面兩種不同設計進行實驗。將洛伐施德丁製備為低濃度(20μM)及高濃度(200μM)兩種劑量在植體植入前塗覆於植體表面上。總共植入一百零八根人工植體在九隻實驗用狗的兩側脛骨上，並且分為二星期及四星期兩個時間點進行觀察。在本實驗中將人工植體分為六組：平滑面植體、平滑面植體塗覆低濃度及高濃度洛伐施德丁、粗糙面植體和粗糙面植體塗覆低濃度及高濃度洛伐施德丁進行實驗。工植體依照隨機分配並平均植入狗的左右兩側脛骨，每一側脛骨將提供六個位置分別給這六組人工植體植入。植體植入位置將鑽成直徑3.85釐米、深10釐米的洞，並將距離骨頭頂端2釐米處擴大為4.2釐米。放置人工植體時並無初期穩定度。物於人工植體植入後兩星期和四星期進行犧牲，脛骨經由解剖並依照植體位置製備成方塊狀，在電子顯微鏡下觀察骨頭與植體表面接觸之百分比以及利用扭力計測試人工植體的移除扭力值。果：經過兩星期的復元，於骨組織型態學分析中發現在平滑面植體的組別中，塗覆洛伐施德丁的平滑面植體相對於對照組具有統計上較大的骨頭與植體表面接觸百分比(P<0.05)。而在四星期後的觀察中也有同樣明顯的發現於平滑面植體的組別中，但是在粗糙面植體的組別中，不論經過兩星期或是四星期的癒合，塗覆有洛伐施德丁的植體相對於對照組並沒有表現顯著性差異在骨頭與植體表面接觸百分比上。移除扭力測試中，經過兩星期的癒合，塗覆有洛伐施德丁的平滑面植體 (14.17 和 13.00牛頓-公分) 比較於沒有塗覆洛伐施德丁的平滑面植體 (9.63 牛頓-公分) 有統計上較高的移除扭力值。但在粗糙面植體組別中並沒有發現此差異。在四星期之後，不論在粗糙面植體或是平滑面植體的組別之間，比較對照組的植體，塗覆洛伐施德丁的植體並沒有的差異在移除扭力值上。較粗糙面植體與平滑面植體兩組之間，在移除扭力測試中，植體植入兩星期或四星期過後，粗糙面植體都具有較高的移除扭力值；而在骨組織型態學分析中，在兩星期後的觀察中，粗糙面植體相較於平滑面植體有統計上較大的骨頭與植體表面接觸百分比，但在四星期後的觀察中，兩者間的差異不再明顯。論：由本實驗所得數據指出，在平滑面人工植體植入後兩星期和四星期，洛伐施德丁能夠在人工植體周圍加快骨頭沈積和改善骨錨定效果，而增加的骨頭與植體表面接觸百分比以及移除扭力值能夠進一步地縮短植體植入後癒合的時間。然而洛伐施德丁之使用劑量以及其給藥方式對於骨整合的影響需要藉由更多的體外和體內試驗來釐清。Objectiveshe 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, i.e., statins, are widely used for the treatment of hyperlipidemia. Recently, experimental studies demonstrated that statins induced the promoter of bone morphogenetic protein-2 (BMP-2) mRNA in osteoblasts and stimulated bone formation. Further, the positive effects of statins on bone formation in animal studies have been reported. ovastatin, a member of the drug class of statins, has the ability to induce bone formation in animal models. The purpose of this study was to compare, histomorphometrically and biomechanically, the bone response to lovastatin coated titanium implants with controls after implantation in the tibia of dogs. aterials and methodsen-mm-long Ti-6Al-4V screw-type implants, with 4mm in diameter were used in the present study. Two different implant surfaces, machined and rough surface were designed for test. The lovastatin was diluted into a low dosage(20μM) and a high dosage(200μM) for implant coating. A total of 108 implants were inserted in the tibia of 9 dogs and assigned into two healing time periods, 2 weeks and 4weeks. The implants were divided into six groups as follows (nine implants in each group): machined surface (M), rough surface (R), machined surface with low-dose lovastatin (ML) and with high-dose lovastatin (MH) , and rough surface with low-dose lovastatin (RL) and with high-dose lovastatin (RH). ach tibia provided six sites assigned to the six implant groups. Location of different implants was assigned according to a randomized schedules established. The implant site was prepared a hole of 3.85mm in diameter and 10mm in depth. The crestal 2.0 mm of implant sites were widened to 4.2mm. There was no primary stability when the implants were inserted into the prepared sites. he animals were sacrificed at 2 weeks or 4 weeks after implant placement. The tibias were dissected and prepared into the block sections of implants. Then, the percentage of bone-to-implant contact (BIC) was observed under scanning electronic microscope, and the removal torque was measured with torque gauge manometer.esults he histomorphometric analysis showed that, after 2 weeks of healing, among the machined surface groups, the percentage of BIC was statistically greater for the lovastatin coated implants than for the controls(P<0.05) and this finding was less evident after 4 weeks. No significant difference was observed among rough surface groups after 2 or 4 weeks of healing. n the removal torque test, the lovastatin-coated machined groups (14.17 and 13.00 Ncm) had statistically higher torque force than non-coated machined group (9.63Ncm) after 2 weeks of healing. But this difference was not found in rough surface groups. At 4 weeks, there were no remarkable difference in removal torque between lovastatin coated implants and control implants, neither among rough surface nor machined surface groups. n removal torque test, there were higher values of removal torque in rough surface groups than those of machined surface groups at 2 or 4 weeks after implantation. In histomorphometric analysis, the rough surface implants had statistically greater BIC than machined surface implants after 2 weeks, but this difference was no longer evident after 4 weeks.onclusionhe data from the present study demonstrated that lovastatin may accelerate new bone deposition and improve bony anchorage around machined surface dental implants after 2 weeks and 4 weeks of healing. The increased BIC and removal torque force suggest the possibility of a further reduction of the healing period following implantation. However, the influences of the dosage of lovastatin and its mode of delivery on osseointegration need more in vitro and in vivo studies to clarify this issue.目 錄試委員會審定書…………………………………………….…..i文摘要……..……………………………………………………..ii文摘要…………………………………………..………………...v錄…………………………...…..…………………………………ixntroduction..…...…………………………………………………1. Surface roughness of dental implants……………………………..21.1 Roughening Implant by Titanium Plasma-spraying Technique...31.2 Roughening Implants by Grit-blasting Method………………...41.3 Roughening Implant by Acid-etching Technique………………51.4 Roughening Implant by Anodization.…………………………..8. Osteoconductive calcium phosphate coatings on titanium implant surface……………………………………………………………..9. Further trends in dental implant surfaces……………………….. 113.1 Nanotechnology and implant surface roughening…………….123.2 Biomimetic calcium phosphate coatings on titanium dental implants……………………………………………………….153.3 Incorporation of biologically active agents in to titanium dental implants……………………………………………………….16 3.3.1 Bone morphogenetic proteins (BMPs)…………………….18 3.3.2 Statins and Lovastatin……………………………………...20. Evaluation of the interface between bone and dental implants….224.1 Biomechanical test……………………………………………22 4.1.1 Pull-out and push-out tests……………………..………….22 4.1.2 Removal torque tests…………………………..…………..234.2 Histomorphometric analysis………………………………….24tudy purpose…………...……………………………………...26aterials and methods……………………………………….26Animals…………………………………………………………..26Experimental design……………………………………………..27Surgical procedure……………………………………………….29Post-operative care………………………………………………30Euthanasia and retrieval of specimens…………………………..32Histomorphometric analysis…………………………………….33Removal torque test……………………………………………..34tatistical analysis………….…………….……………………...34ESULTS………………………………………………………35Clinical observation……………………………………………...35Histomorphometric observation and measurements……………..36Removal torque tests……………………………………………..39iscussion…………………………….…………………………40Implant complication…………………………………………….41Implant surface roughness and osseointegration………………...42The effect of implant coated with lovastatin in osseointegration..44The limitations of the present study……………………………..46onclusion……………………………………………………...48eferences………………………………………………………49igures Fig. 1 Two different implant surfaces were designed for test………………………………………..………………..56Fig. 2 A skin incision about 6~7 cm in length over the medial tibia exposed the medial surface of the tibia. The periosteum was incised and elevated for implantation……………………..57Fig. 3 The implantation site was prepared by using high-torque handpiece (a) (KAVO, INTRAmatic 7C, modified) and trephine burs (b) with constant water irrigation…………..58Fig. 4 The preparation of implant site (mm)…………………….58Fig. 5 Each tibia provided six sites assigned to the six experimental groups. The distance among implants was at least 2–3mm. The implants were covered with resin cap…………………….59Fig. 6 The tibias were dissected between implant and implant by using a diamond saw(IsoMet® 2000 Precision Saw, Buehler, USA) and got block sections of the implant………………59Fig. 7 Each implant was cut in the mesiolateral direction and along with the long axis of the implant by using a diamond saw, resulting in two central sections for histomorphometric analysis…………………………………………………….59Fig. 8 Ground sections of titanium implant with different surface treatment after 2 weeks of healing (SEM, original magnification X25~30)……………………………………60Fig. 9 Ground sections of titanium implant with different surface treatment after 4 weeks of healing (SEM, original magnification X25~30)……………………………………61Fig. 10 The percentage of bone–to-implant contact (BIC%) was then calculated and analyzed with the software Image J 1.41. The contact was calculated at 3 different parts: (A) Total BIC; (B) The cortical BIC (red double arrows); The cancellous BIC (blue double arrows)……………………………………..62Fig. 11 The specimens were connected the abutments(B) and stabilized in a jig(C), then received reversed torque with a torque gauge monometer(15BTG, Tohnichi, Tokyo, Japan ) until the implants started to rotate and recorded the maximum removal torque value…………………………………….62Fig. 12 (A) Boxplots with outliners for the medians and Q1-Q3 quartiles of BIC% of total implant length in different groups after 2 weeks of healing. (B) The mean BIC% with SD of total implant length in different groups after 2 weeks of healing…………………………………………………...63Fig. 13 (A) Boxplots with outliners for the medians and Q1-Q3 quartiles of BIC% of total implant length in different groups after 4 weeks of healing. (B) The mean BIC% with SD of total implant length in different groups after 4 weeks of healing……………………………………………….......64Fig. 14 (A) Boxplots with outliners for the medians and Q1-Q3 quartiles of BIC% of cortical bone in different groups after 2 weeks of healing. (B) The mean BIC% with SD of cortical bone in different groups after 2 weeks of healing……….65Fig. 15 (A) Boxplots with outliners for the medians and Q1-Q3 quartiles of BIC% of cortical bone in different groups after 4 weeks of healing. (B) The mean BIC% with SD of cortical bone in different groups after 4 weeks of healing……….66Fig. 16 (A) Boxplots with outliners for the medians and Q1-Q3 quartiles of BIC% of cancellous bone in different groups after 2 weeks of healing. (B) The mean BIC% with SD of cancellous bone in different groups after 2 weeks of healing…………………………………………………...67Fig. 17 (A) Boxplots with outliners for the medians and Q1-Q3 quartiles of BIC% of cancellous bone in different groups after 4 weeks of healing. (B) The mean percentages of BIC of cancellous bone in different groups after 4 weeks of healing……………………………………………………68Fig. 18 (A) Boxplots with outliners for the medians and Q1-Q3 quartiles of removal torque in different groups after 2 weeks of healing. (B) The mean removal torque values in different groups after 2 weeks of healing………………………….69Fig. 19 (A) Boxplots with outliners for the medians and Q1-Q3 quartiles of removal torque in different groups after 4 weeks of healing. (B) The mean removal torque values in different groups after 4 weeks of healing………………………….70ablesTable 1. The position, surface specification and healing period of each implant…………………………………………….71Table 2. The implant sample number of each healing period for two tests: (A) 2weeks; (B) 4weeks………………………….72Table 3. Histomorphometric measurements of the bone-to-implant contact(BIC) in percentage(%) 2weeks after implant placement.—total BIC………………………………….73Table 4. Histomorphometric measurements of the bone-to-implant contact(BIC) in percentage(%) 4weeks after implant placement.—total BIC………………………………….73Table 5. Histomorphometric measurements of the bone-to-implant contact(BIC) in percentage(%) 2weeks after implant placement.—cortocal bone……………………………..74Table 6. Histomorphometric measurements of the bone-to-implant contact(BIC) in percentage(%) 4weeks after implant placement.—cortical bone……………………………...74Table 7. Histomorphometric measurements of the bone-to-implant contact(BIC) in percentage(%) 2weeks after implant placement.—cancellous bone…………………………..75Table 8. Histomorphometric measurements of the bone-to-implant contact(BIC) in percentage(%) 4weeks after implant placement.—cancellous bone…………………………...75Table 9. Results of removal torque(in Ncm) 2weeks after implant placement……………………………………………….76Table 10. Results of removal torque(in Ncm) 4weeks after implant placement……………………………………………….76application/pdf2553442 bytesapplication/pdfen-US表面結構形態移除扭力骨頭與植體表面接觸骨整合洛伐施德丁鈦六鋁四釩人工植體surface topographyremoval torquebone-to-implant contactosseointegrationlovastatinTi-6Al-4V titanium implanthttp://ntur.lib.ntu.edu.tw/bitstream/246246/184190/1/ntu-98-R95422010-1.pdf