| 摘要: | 本研究分為三部分：
第一部分：本研究旨在分析通過在兔腿骨上植入氧化316L生物醫用不鏽鋼（BSS）小型植入物來分析其恢復期。316L BSS小型植入物通過電化學陽極氧化法在不同電壓下進行修改。經氧化的樣品通過場發射掃描電子顯微鏡、X射線衍射和X射線光電子能譜學進行表徵。生物相容性通過細胞培養試驗進行評估。氧化的小型植入物植入兔的股骨後，分別在植入後4和8周進行組織學評估。分析結果表明，5 V氧化5分鐘後，氧化小型植入物的表面結構由雙孔（微/納米）結構組成。在氧化5 V 5分鐘後，樣品表面形成了Cr2O3的氧化膜。體外細胞培養試驗顯示，NIH-3T3成纖維細胞在氧化樣品上的附著性比對照樣品更牢固。此外，組織學分析顯示，氧化小型植入物在植入後4周改善了骨恢復。因此，本研究建議，氧化316L BSS小型植入物可能是作為牙齒矯正治療有效和高效錨定裝置的潛在選擇。
第二部分：本研究闡明了金屬氧化鈦（TiO）薄膜與磷酸自組裝單層（SAMs）交聯的表面特性、微結構和生物相容性。通過掃描電子顯微鏡、原子力顯微鏡、X射線衍射、透射電子顯微鏡和體外細胞培養試驗，該研究發現，在使用11-磷酸十一烷酸溶液（PUA-SAM/TiO）交聯後，樣品表面形成了相對均勻且平坦的SAM，粗糙度為3.09 ± 0.32納米。研究的SAMs微結構由非晶結構組成。此外，生物相容性試驗和細胞附著反應的分析結果還表明，PUA-SAM/TiO樣品在培養初期（24小時）具有更好的MG-63類骨母細胞附著和增殖能力。因此，這些發現揭示了以磷酸自組裝單層作為目標仿生表面的形成，可能有助於促進生物醫學鈦植入物的早期骨融合。
第三部分：本研究旨在探討含有骨形成蛋白-2（BMP-2）的膠原海綿體結合牙科植入物在豬模型中的骨形成效能。將兩種重組人骨形成蛋白-2（rhBMP-2）濃度，20和40 ng/?L，融入膠原海綿體中，並置於鈦牙科植入物的底部。使用含有和不含有膠原海綿體的植入物進行比較分析。隨後，將植入物插入Lanyu小耳豬犬臼齒前磨牙區的無牙脊。動物在植入後1、2、4、8和12周被犧牲，並收集含有植入物和周圍骨組織的樣本進行骨-植入物接觸（BIC）比率的組織學評估，以及使用移除扭矩測量計算最大扭矩。載有BMP-2的植入物顯示出比沒有BMP-2的植入物更高的骨形成和移除扭矩值。然而，骨-植入物接觸和移除扭矩之間未觀察到顯著差異。這些結果表明，通過膠原海綿體傳遞的BMP-2可能增強牙科植入物的早期骨融合。
The present study is comprised of three parts:
Part I: Anodized Biomedical Stainless-Steel Mini-Implant for Rapid Recovery in a Rabbit Model
The study aimed to analyze the recovery period of the anodized 316L biomedical stainless steel (BSS) mini-implant through its implantation on femur of rabbit model. The 316L BSS mini-implant was modified by an electrochemical anodization approach with different voltages. The anodized samples were characterized via field-emission scanning electron microscopy, X-ray diffractometry, and X-ray photoelectron spectroscopy. The biocompatibility was assessed by cell culture assay. The anodized mini-implant was implanted on rabbit’s femur then evaluated histologically after 4 and 8 weeks. Analytical results indicated that the topography of the anodized mini-implant at 5 V for 5 min consisted of a dual (micro/nano) porous structure. Oxide film of Cr2O3 was formed on the surface of anodized mini-implant after anodizing with 5 V for 5 min. In vitro cell culture assay revealed that fibroblast cells (NIH-3T3) on the anodized samples were more firmly attached as compared with the control sample. Moreover, histological analysis demonstrated that the anodized mini-implant improved bone recovering at 4 weeks after im-plantation. Thus, this study suggests that the anodized 316L BSS mini-implant could be a potential choice as an anchorage device for effective and efficient orthodontic treatment.
Part II: A promising biomimetic surface enhances cell proliferation and adhesion ability for promoting early-stage osseointegration
The surface characteristics, microstructures, and biocompatibility of the metal titanium oxide (TiO) film cross-linked with different self-assembled monolayers (SAMs) of phosphonate were elucidated through scanning electron microscopy, atomic force microscopy, X-ray diffractometry, transmission electron microscopy, and in vitro cell culturing assay in the present study. It was found that a relatively uniform and flat SAM with a roughness of 3.09 ± 0.32 nm can be formed on the specimen surface after cross-linking with 11-phosphonoundecanoic acid solution (PUA-SAM/TiO). The microstructures of the investigated SAMs were composed of amorphous structure. Moreover, analytical results from the biocompatibility assay and cell adhesion response also demonstrated that the PUA-SAM/TiO specimen possesses better osteoblast-like MG-63 cell adhesion and proliferation ability at the early time point of culturing (24 h). Thus, these findings reveal that the formation of SAM of phosphonate as the targeted biomimetic surface could potentially promote early-stage osseointegration for biomedical Ti implants.
Part III: An innovative design to enhance osteoinductive efficacy and biomechanical behavior of a titanium dental implant
The present study aimed to investigate the in vivo bone-forming efficacy of a dental implant combined with collagen sponges containing bone morphogenetic protein-2 (BMP-2) in a pig model. Two recombinant human bone morphogenetic protein-2 (rhBMP-2) concentrations, 20 and 40 ng/?L, were incorporated into collagen sponges and placed at the bottom of titanium dental implants. Implants with and without the collagen sponge were used for comparative analysis. Subsequently, the implants were inserted into the edentulous ridge at the canine-premolar regions of Lanyu small-ear pigs. Animals were sacrificed at 1, 2, 4, 8, and 12 weeks after implantation, and specimens containing the implants and surrounding bone tissue were collected for histological evaluation of bone-to-implant contact (BIC) ratio and calculation of maximum torque using removal torque measurement. The implants loaded with BMP-2 exhibited higher bone formation and removal torque values than those without BMP-2. However, no significant differences were observed in bone-implant contact and removal torque. These findings indicate that BMP-2, delivered via a collagen sponge, can potentially enhance early osseointegration of dental implants. |
