Department of Conservative Dentistry and Prosthodontics, School of Dentistry, Complutense University of Madrid, Madrid, Spain.
Department of Prosthetic Dentistry, School of Dentistry, European University of Madrid, Madrid, Spain.
J Dent. 2022 Jun;121:104122. doi: 10.1016/j.jdent.2022.104122. Epub 2022 Apr 6.
To assess the influence of the scan body geometry bevel location and implant angulation and position of complete-arch implant digital scans.
Two definitive casts with 4 implant analogs placed parallel (P group) or angulated up to 30° (NP group) were fabricated. Five subgroups were created based on the scan body geometry bevel position: facial, mesial, distal, lingual, or random (F, M, D, L, and R subgroup). Casts were digitized using a laboratory scanner (reference) (7Series Desktop Scanner) and an intraoral scanner (TRIOS 3). The implant position discrepancies between the reference and experimental scans were calculated. Data was analyzed using 3-way ANOVA and Tukey tests (α = .05).
The scan body geometry bevel position (P < .001) and the inter-implant distance (P < .001) were shown as significant predictors of the linear discrepancies obtained. The L subgroup had a significantly lower discrepancy compared with the other subgroups. Implant angulation (P < .001), the scan body geometry bevel position (P < .001), and the inter-implant distance (P < .001) were all significant predictors on the angular discrepancies obtained.
The scan body geometry bevel location and implant angulation and position influenced the accuracy of the IOS tested. The lingual orientation obtained significantly better accuracy values compared with the other positions. The parallel implant analog position obtained better accuracy than the angulated positions. Lastly, the implant positioned in the dental arch where the intraoral digital scan was finished obtained significantly higher distortion than the contralateral implant.
评估扫描体几何斜面位置和种植体角度以及全口种植体数字扫描的位置对扫描结果的影响。
制作了两组带有 4 个种植体模拟体的最终模型，模拟体被平行放置（P 组）或成 30°角放置（NP 组）。基于扫描体几何斜面位置，创建了 5 个亚组：颊侧、近中、远中、舌侧或随机（F、M、D、L 和 R 亚组）。使用实验室扫描仪（参考扫描仪）（7Series Desktop Scanner）和口内扫描仪（TRIOS 3）对模型进行数字化。计算参考扫描和实验扫描中种植体位置的差异。使用 3 因素方差分析和 Tukey 检验（α=.05）对数据进行分析。
扫描体几何斜面位置（P<.001）和种植体之间的距离（P<.001）是线性差异的显著预测因子。与其他亚组相比，L 亚组的差异显著较小。种植体角度（P<.001）、扫描体几何斜面位置（P<.001）和种植体之间的距离（P<.001）是获得的角度差异的显著预测因子。
扫描体几何斜面位置、种植体角度和位置影响了所测试 IOS 的准确性。与其他位置相比，舌侧方向的准确性显著更高。平行放置的种植体模拟体位置比成角位置的准确性更高。最后，在口内数字扫描完成的牙弓内放置的种植体比对侧种植体获得的失真程度更高。
