Objective

This study evaluates the effect of dynamic-loading on the microgap of the IAC when different supratructure heights are applied. Materials and methods: Forty-eight dental implants (24 each of butt-joint (H) and internal-conical connections (C)) were tested in this study. Each group was further divided into three groups (n = 8) according to the applied suprastructure height (H1, C1: 10 mm, H2, C2: 14 mm and H3, C3: 18 mm). All specimens were subjected to cyclic loading in a chewing-simulator with a load of 98 N for 5 × 10⁶ chewing cycles. The microgap at the IAC was inspected before and after loading, using synchrotron-based micro computed tomography (SRμCT) and light microscopy (LM). Results: SRμCT revealed an internal microgap range between 0.26 μm and 0.5 μm in the group C, whereas the group H exhibited a microgap range between 0.26 μm and 0.47 μm prior to loading. After chewing simulation, a smaller microgap size in all groups was detected ranging from 0.11 μm to 0.26 μm (group C: 0.11μm–0.26 μm; group H: 0.21μm–0.25 μm). The LM investigation showed mean microgap values at the outer IAC junction before loading from 5.8 μm to 11.3 μm and from 3.9 μm to 7.2 μm after loading. All specimens exhibited a vertical intrusion displacement of the abutment. Conclusion: Regardless of the crown height, the microgap between the abutment and implant systematically decreased after loading in both butt-joint and internal-conical connections.

中文翻译：

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基于同步加速器的计算机断层摄影术对种植体-基台疲劳引起的微间隙变化的研究

目的

这项研究评估了当应用不同的结构高度时，动态载荷对IAC的微间隙的影响。材料和方法：在此研究中测试了48个牙科植入物（对接（H）和内圆锥形连接（C）各24个）。根据应用的超结构高度（H1，C1：10毫米，H2，C2：14毫米和H3，C3：18毫米）将每组进一步分为三组（n = 8）。所有样品均在咀嚼模拟器中承受5 N×10 ⁶的98 N载荷的循环载荷咀嚼周期。使用基于同步加速器的微型计算机断层扫描（SRμCT）和光学显微镜（LM），在加载前后检查IAC的微间隙。结果：SRμCT显示，C组的内部微间隙范围在0.26μm至0.5μm之间，而H组在加载前的微间隙范围在0.26μm至0.47μm之间。咀嚼模拟后，所有组的微间隙尺寸均较小，范围为0.11μm至0.26μm（C组：0.11μm–0.26μm； H组：0.21μm–0.25μm）。LM研究显示，加载前，IAC外部结的平均微间隙值从5.8μm增至11.3μm，加载后从3.9μm增至7.2μm。所有样品均显示基台的垂直侵入位移。结论：无论冠高，