Department of Prosthodontics - School of Dental Medicine, Justus Liebig University, Giessen, Germany.
Dental Surgery, Haiger, Germany.
Clin Oral Implants Res. 2021 Apr;32(4):460-469. doi: 10.1111/clr.13715. Epub 2021 Feb 2.
The objective of this study was to systematically compare the transfer accuracy of conventional and digital implant impressions in patients using a new reference key-based method.
Thirty-nine cases were included in the study (upper jaw 22 edentulous, 8 partially edentulous, average distance between implants 30.15 ± 11.18 mm; lower jaw 6 cases edentulous, 3 cases partially edentulous, average distance between implants 33.19 ± 14.85 mm). Individual reference keys were manufactured and reversibly fixed on implants. A conventional (CVI) and a digital (DI) implant impression was made. The implant positions (center points) of conventional and digital models were measured (coordinate-measuring machine/three-dimensional analysis software) and superimposed with the positions of the reference keys to compare the deviations of the conventional and digital models. For statistical analysis, ANOVA with MIXED procedure was applied (p < .05).
Mean deviation ranged from 0.040±0.029 mm (DI/upper jaw) to 0.079 ± 0.050 mm (DI/lower jaw). There were significant differences between the CVI and DI impressions in the lower jaw (p < .05). No significant differences in transfer accuracy were found between partially and completely edentulous patients for the impression methods.
Within the limits of the present study, it can be concluded that full-arch digital implant impressions of the upper jaw in partially or completely edentulous patients showed comparable results to conventional implant impressions. However, with regard to the implant position transfer accuracy, there are still limitations for digital impression in the lower jaw.
本研究旨在通过一种新的基于参考键的方法，系统比较常规和数字化种植体印模在患者中的转移精度。
本研究纳入了 39 例患者（上颌 22 例无牙，8 例部分牙缺失，种植体之间的平均距离为 30.15±11.18mm；下颌 6 例无牙，3 例部分牙缺失，种植体之间的平均距离为 33.19±14.85mm）。制造了个性化的参考键并将其可逆地固定在种植体上。制取常规（CVI）和数字化（DI）种植体印模。使用坐标测量机/三维分析软件测量常规和数字化模型的种植体位置（中心点），并将其与参考键的位置进行叠加，以比较常规模型和数字化模型的偏差。采用方差分析混合程序进行统计分析（p<.05）。
平均偏差范围为 0.040±0.029mm（DI/上颌）至 0.079±0.050mm（DI/下颌）。在下颌，CVI 和 DI 印模之间存在显著差异（p<.05）。对于两种印模方法，部分牙缺失和完全牙缺失患者的转移精度无显著差异。
在本研究的范围内，可以得出结论，在上颌部分或完全牙缺失的患者中，全口数字化种植体印模与常规种植体印模具有相似的结果。然而，在种植体位置转移精度方面，数字化印模在下颌仍然存在局限性。
