Narrow-diameter implants (NDIs) traditionally have been associated to higher rates of failure in comparison with regular-diameter implants (RDIs) and wide-diameter implants (WDIs), since they generate a more unfavorable stress distribution in peri-implant bone. However, it is well known that the load sharing effect associated with prostheses supported by multiple implants (also called splinted prostheses) affords mechanical benefits. The present study involves finite element analysis (FEA) to determine whether the risks linked to NDIs could be mitigated by the mechanical advantages afforded by the splinting concept. For this purpose, a three-dimensional (3D) model of a real maxilla was reconstructed from computed tomography (CT) images, and different implants (NDIs, RDIs and WDIs) and prostheses were created using computer-aided design (CAD) tools. Biting forces were simulated on the prostheses corresponding to three different rehabilitation solutions: single-implant restoration, three-unit bridge and all-on-four treatment. Stress distribution around the implants was calculated, and overloading in bone was quantified within peri-implant volumes enclosed by cylinders with a diameter 0.1 mm greater than that of each implant. The mechanical benefits of the splinting concept were confirmed: the peri-implant overloaded volume around NDIs splinted by means of the three-unit bridge was significantly reduced in comparison with the nonsplinted condition and, most importantly, proved even smaller than that around nonsplinted implants with a larger diameter (RDIs). However, splinted NDIs supporting the all-on-four prosthesis led to the highest risk of overloading found in the study, due to the increase in compressive stress generated around the tilted implant when loading the cantilevered molar.

与常规直径植入物（RDI）和宽直径植入物（WDI）相比，传统上，窄直径植入物（NDI）与较高的失败率相关，因为它们在植入物周围的骨中产生更不利的应力分布。但是，众所周知，与由多个植入物（也称为夹板假体）支撑的假体相关的负载分担效果具有机械上的好处。本研究涉及有限元分析（FEA），以确定夹板概念提供的机械优势是否可以减轻与NDI相关的风险。为此，从计算机断层扫描（CT）图像重建了真正的上颌骨的三维（3D）模型，并使用计算机辅助设计（CAD）工具创建了不同的植入物（NDI，RDI和WDI）和假体。在假体上模拟咬合力，对应三种不同的康复解决方案：单种植体修复，三单元牙桥和全四肢治疗。计算植入物周围的应力分布，并在直径大于每个植入物直径0.1 mm的圆柱体围成的植入物周围体积内量化骨骼的超负荷。夹板概念的机械优势得到了证实：与非夹板情况相比，通过三单元桥夹住的NDI周围的植入物周围的超载体积显着减少，最重要的是，事实证明甚至比非夹板植入物周围的更小。较大的直径（RDI）。但是，支持全四肢假体的夹板NDI导致研究中出现超负荷的最高风险，