| 摘要: | 牙科植體-齒槽骨界面骨整合發展為考量術後置放假牙之重要因素，若骨整合不佳，通常伴隨骨缺損現象出現，致使界面穩固度降低，造成手術失敗，故諸多研究對此開發檢測技術與裝置，但迄今仍無法提供決定術後成敗之診斷標準，且各法亦存在限制及缺點。本研究提出非接觸式聲能激振-位移響應量測技術，並進行體外/體內測試，體外實驗方面，設計各類單/對側骨缺損模型與邊界固定高度，待癒合帽鎖附且固定於金屬虎鉗座後量測，利用喇叭產生聲能掃頻訊號激振模型，電容式位移計接收振動響應訊號，取得響應頻譜之第一峰值共振頻率，經統計分析，探討共振頻率、缺損結構與邊界固定條件之關係，該結果亦與市售檢測儀ISQ及有限元素模擬值比較，可知：單/對側缺損之垂直深度增加，共振頻率下降，虎鉗固定高度增加，各模型頻率上升，皆具顯著差異；另共振頻率變化與ISQ值具高相關性，且數值模態分析之共振頻率亦呈現相同變化趨勢。體內動物實驗方面，將有無表面塗佈處理之兩植體，嵌入白兔左脛骨並鎖附癒合帽後縫合，於骨整合過程，以自行發展技術與市售檢測儀量測比較，結果經統計分析後知：兩植體之側向頻率高於軸向，未塗佈1號植體於第24週量測之軸向頻率比第16週高，已塗佈之2號植體側向頻率高於1號，具顯著差異，證明本技術檢測值可反映骨整合情況，且表面處理可促進其發展；另1號側向/2號側軸向於兩週量測頻率比較、兩植體軸向頻率比較與第24週ISQ值差異不明顯處，需規劃詳細動物實驗探討確認。因此，本研究建立之非接觸式量測技術，可有效評估體外骨缺損，亦能初步檢測體內骨整合，並改善現存技術接觸式激振和質量負載效應影響，後續將改善相關量測問題，搭配體內/外測試驗證，期能使該技術完備，協助醫師術後診斷及病患即時監測，降低植牙手術失敗風險。
Several methods have been developed and applied to assess the interfacial situations after the dental implantation, but so far they are not able to provide the diagnostic standard for determining the success and the failure of the surgery. This study, establishing a newly noncontact resonance frequency (RF) detection technique, uses the procedure to perform bone defect and osseointegration evaluation in the implant-bone interface. Based on our method, the implant-bone structure was excited by the acoustic energy of a loudspeaker, and its vibration response was acquired with a capacitance displacement sensor. The spectral analysis was used to characterize the first peak RF value. Two types of in vitro defect models, single vertical dehiscence (SVD) and opposite vertical dehiscence (OVD), were 4 and 8 mm in depth and made for verification. The measurements of RF with each model being clamped in four heights (9, 10, 11, and 12 mm) were performed in their defect directions (0°, 45° and 90°), respectively. Afterward the finite element (FE) modal analysis was applied to determine mode shapes as well as their corresponding RFs of these bone defect models and compared simulated results with measuring RFs. Besides, two implants (1: coating, 2: non coating) were embedded in the left tibia of one rabbit. This noncontact method was used to perform the preliminary osseointegration detection and measured the RFs of the tibia in the lateral as well as the axial direction. Each in vitro and in vivo model was also checked by using an Osstell Mentor. The obtained two parameters, RF and ISQ (Implant Stability Quotient), were tested statistically by the ANOVA and the linear regression analysis for comparisons. In the in vitro test, the RFs and the ISQs of all defect models in four clamp heights decrease significantly (p < 0.05) along with the increase of the defect quantity
and the two parameters of each imperfection increase significantly (p < 0.05) when the clamp height increases. The RFs of SVD models linearly correlate with their corresponding ISQs in four clamp heights and two measuring orientations (0° and 90°). The numerical RF variations also present the same trend along with the changing of the defect structure and the surrounding boundary condition. Additionally, in the in vivo test, the RFs of two implants in the lateral direction are higher than that in the axial direction (p < 0.05). The axial RFs of the implant 1 in the 24 week are higher than that in the 16 week, and the lateral RFs of the implant 2 are higher than those of the implant 1 (p < 0.05). Other unapparent differences in some RF and ISQ detection need detailed animal experiments to confirm. Therefore, our technique can estimate availably the interfacial imperfection/osseointegration and is feasible for the assessment of the postoperative healing around a dental implant. |
