ObjectivesThe purpose of this in vitro study was to compare the trueness and precision of complete arch implant impressions using conventional impression, intraoral scanning with and without splinting, and stereophotogrammetry.Materials and MethodsAn edentulous model with six implants was used in this study. Four implant impression techniques were compared: the conventional impression (CI), intraoral scanning (IOS) without splinting, intraoral scanning with splinting (MIOS), and stereophotogrammetry (SPG). An industrial blue light scanner was used to generate the baseline scan from the model. The CI was captured with a laboratory scanner. The reference best‐fit method was then applied in the computer‐aided design (CAD) software to compute the three‐dimensional, angular, and linear discrepancies among the four impression techniques. The root mean square (RMS) 3D discrepancies in trueness and precision between the four impression groups were analyzed with a Kruskal–Wallis test. Trueness and precision between single analogs were assessed using generalized estimating equations.ResultsSignificant differences in the overall trueness (p = .017) and precision (p < .001) were observed across four impression groups. The SPG group exhibited significantly smaller RMS 3D deviations than the CI, IOS, and MIOS groups (p < .05), with no significant difference detected among the latter three groups (p > .05).ConclusionsStereophotogrammetry showed superior trueness and precision, meeting misfit thresholds for implant‐supported complete arch prostheses. Intraoral scanning, while accurate like conventional impressions, exhibited cross‐arch angular and linear deviations. Adding a splint to the scan body did not improve intraoral scanning accuracy.

中文翻译：

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无牙全牙弓种植体印模的准确性：传统印模、带夹板和不带夹板的口内扫描以及摄影测量之间的体外比较

目的本体外研究的目的是比较使用传统印模、带或不带夹板的口内扫描以及立体摄影测量法获得的全牙弓种植体印模的真实性和精确度。材料和方法本研究使用具有六颗种植体的无牙颌模型。比较了四种种植体印模技术：传统印模（CI）、不带夹板的口内扫描（IOS）、带夹板的口内扫描（MIOS）和立体摄影测量（SPG）。使用工业蓝光扫描仪从模型生成基线扫描。CI 是用实验室扫描仪捕获的。然后将参考最佳拟合方法应用于计算机辅助设计（CAD）软件中，以计算四种印模技术之间的三维、角度和线性差异。使用 Kruskal-Wallis 检验分析四个印象组之间的均方根 (RMS) 3D 真实性和精确度差异。使用广义估计方程评估单个类似物之间的真实度和精度。结果总体真实度存在显着差异（p= .017) 和精度 (p< .001) 在四个印象组中观察到。SPG 组的 RMS 3D 偏差明显小于 CI、IOS 和 MIOS 组（p< .05），后三组之间没有检测到显着差异（p> .05).结论立体摄影测量显示出卓越的真实性和精确度，满足种植体支持的全弓假体的失配阈值。口内扫描虽然像传统印模一样准确，但表现出跨牙弓角度和线性偏差。在扫描主体上添加夹板并不能提高口内扫描的准确性。