植入上颌后部区域的骨内种植体的长期成功率低于植入其它区域者。上颌后部区域的缺点是 :骨质地差 ;临近上颌窦 ,因此 ,不可能植入较长的种植体 ;合负荷较高 ;合平台( occlusal table)常常宽于种植体直径 ,造成近远中悬臂、颊舌向悬臂和离开长轴的 ( off- axis)力。本研究评价 The long-term success rate of intraosseous implants implanted in the posterior maxillary region was lower than those implanted in other regions. Shortcomings of the posterior maxilla are: poor bone quality; near the maxillary sinus; therefore, it is not possible to implant longer implants; higher combined loads; occlusal tables are often wider than the implant diameter, resulting in a short distance Middle cantilever, cantilevering, and off-axis force away from the long axis. This study evaluates