Survival and complication rates of two dental implant systems supporting fixed restorations: 10-year data of a randomized controlled clinical study

OBJECTIVES To compare clinical, radiographic, biological and technical long-term outcomes of two types of dental implants over a period of 10 years. MATERIALS AND METHODS Ninety-eight implants were placed in 64 patients, randomly allocated to one of two manufacturers (AST and STM). All implants were loaded with fixed restorations. Outcome measures were assessed at implant insertion (T$_{i}$), at baseline examination (T$_{L}$), at 1, 3, 5, 8 and 10 (T$_{10}$) years. Data analysis included survival, bone level changes, complications and clinical measures. RESULTS Re-examination was performed in 43 patients (23 AST and 20 STM) at 10 years. The implant level analysis was based on 37 (AST) and 32 (STM) implants. Survival rates of 100% were obtained for both groups. The median changes of the marginal bone levels between baseline and T$_{10}$ (the primary endpoint) amounted to a loss of 0.07 mm for group AST and a gain of 0.37 mm for group STM (intergroup p = 0.008). Technical complications occurred in 27.0% of the implants in group AST and in 15.6% in group STM. The prevalence of peri-implant mucositis was 29.7% (AST) and 50.1% (STM). The prevalence of peri-implantitis amounted to 0% (AST) and 6.3% (STM). CONCLUSIONS Irrespective of the implant system used, the survival rates after 10 years were high. Minimal bone level changes were observed, statistically significant but clinically negligible in favor of STM. Technical complications were more frequently encountered in group AST, while group STM had a higher prevalence of peri-implant mucositis

Multi-Objective Optimal Control Strategies of the Locomotor System of Young Women in High-Heeled During Obstacle-Crossing

隨著社會經濟的高度發展，許多女性因專業考量或追求流行等原因逐漸開始穿著高跟鞋。腳跟高度的增加將無疑地提高神經骨骼肌肉系統的挑戰、增加維持平衡的困難度及增加跌倒的風險，常導致骨折或是還關節扭傷的發生，而跨越障礙物更增加了維持平衡的困難度以及跌倒的風險。過去有相當多針對穿著高跟鞋步行以及跨越障礙物的研究，但大多數著重於運動學、力動學以及身體質量中心與壓力中心資訊所造成的影響，而結果仍是眾說紛紜，且僅能探討個別關節表現較難以判斷整體動作的控制策略。透過本實驗室所開發的多目標最佳控制方法，定義跨越障礙物之目標函數可由最小能量消耗與最大足部間隙兩個互為衝突的目標妥協而成，並可描述跨越障礙物之整體控制策略。 本研究選取14位經常穿著高跟鞋的年輕女性於跨越障礙物動作時之三維運動資訊，並利用本實驗室所開發的多目標最佳控制方法，探討年輕女性穿著高跟鞋後對於執行跨越障礙物動作時之控制策略的影響，並逐一比較不同障礙物高度以及不同鞋跟高度所可能產生的影響。結果顯示，年輕女性穿著高跟鞋後並不影響跨越障礙物的控制策略，亦不受到障礙物高度以及鞋跟高度的影響，能量消耗權重值大約介於0.46至0.78區間，顯示年輕女性在穿著高跟鞋之後，對於能量消耗以及足部間隙的妥協並不受到影響。其原因主要來自於當穿著高跟鞋後並不影響擺盪腳由站立期進入擺盪期的過程以及本體對於足部的位置感知的影響，使穿著者仍保持與赤腳時相同的運動控制策略，且過往研究也證實人體能以動作程式的模式執行特性的動作，因此當高跟鞋所產生的干擾介入時，人體仍以相同的控制策略來執行跨越障礙物的動作。 對於過往利用大量參數探討穿著高跟鞋跨越障礙物之資訊，不僅難以完整描述整體之控制策略，且結果仍無法完全一致；本研究能提供一個簡易且明確的方法來探討年輕女性穿著高跟鞋跨越障礙物時之控制策略，藉此了解穿著高跟鞋後執行跨越障礙物動作所產生的影響。With the highly developed of social economy, many women wear high-heeled shoes in both professional and fashionable settings. The elevation of the heel height increases the challenge to the neuromusculoskeletal system, leading to injuries such as fracture and ankle sprain. The obstacle crossing also increases the difficulty of balance control and the risk of falling. There are many studies about the level walking and obstacle crossing with high-heeled shoes but most of them focus on the influence of kinematics, kinetics, center of mass and center of pressure. However, the results still remains controversial and unable to discover the overall control strategies of the whole motion. With the algorithm of multi-objective optimal control (MOOC) technique in our laboratory, we suggested that obstacle-crossing was formulated as an optimal control problem with two conflicting objectives: minimization of mechanical energy expenditure and maximization of foot-obstacle clearance and able to describe the overall control strategies during obstacle crossing. The purposes of the present study were to investigate the effects of control strategies of young women in high-heeled during obstacle crossing through the multi-objective optimal control technique and analyze the effects of obstacle height and shoes height respectively. Fourteen female habitual wearer’s 3D kinematics and kinetics information during obstacle crossing were selected in the present study. No significant difference was found in any obstacle height and heel height condition. The weighting of energy expenditure is about 0.46 to 0.76. It appears that the compromise between mechanical energy expenditure and foot-obstacle clearance is not affected after wearing the high-heeled shoes. The main reason for this is not only due to the process from stance phase to swing phase of swing limb was not influenced while the heel height was increased but also the interference of proprioception. Some studies proved that some particular classes of action are executed as a motor program. Thus, wearer remain the same control strategies in high-heeled during obstacle crossing. Using a large number of parameter to explore the obstacle crossing is difficult to describe to control strategies of whole motion and the results are still not fully consistent. The results of this study can provide a simpler and clearer tool to describe the control strategies in high-heeled during obstacle-crossing.致謝 I 摘要 II Abstract IV 第1章 緒論. 1 1.1 研究背景 1 1.2 跨越障礙物 1 跨越腳(Leading Limb)與站立腳(Trailing Limb) 2 足部間隙(Foot Clearance) 3 跨越障礙物之運動學分析 4 跨越障礙物之力動學分析 5 跨越障礙物之平衡分析 5 1.3 最佳控制方法 7 1.4 研究目的 8 第2章 材料與方法 9 2.1 受試者 9 2.2 高跟鞋 9 2.3 實驗器材 10 2.4 實驗流程 11 2.5 資料處理 14 局部座標系統定義 14 廣義/局部座標系統轉換 20 測力板反作用力 21 2.6 數據分析 22 二維人體模型建立 22 七連桿運動學 23 逆向動力學 25 2.7 跨越障礙物之最佳控制 33 最佳控制方法 33 2.8 單目標最佳控制模式數學模型 36 設計變數： 36 目標函數： 36 限制條件 38 2.9 多目標最佳控制模式數學模型 39 設計變數： 39 目標函數： 40 限制條件： 40 2.10 單目標與多目標最佳控制收斂軌跡 41 2.11 統計分析 43 第3章 結果 44 3.1 障礙物高度差異 44 3.2 鞋跟高度差異 46 第4章 討論 47 4.1 穿著高跟鞋跨越障礙物 47 4.2 障礙物高度差異 48 4.3 鞋跟高度差異 48 4.4 腳趾間隙與腳跟間隙比例 49 4.5 研究限制與未來展望 49 第5章 結論 50 參考文獻 5