Waldecker Moritz, Jetter Karla, Rues Stefan, Rammelsberg Peter, Zenthöfer Andreas
Department of Prosthetic Dentistry, University Hospital Heidelberg, University of Heidelberg, 69120 Heidelberg, Germany.
Materials (Basel). 2025 May 7;18(9):2164. doi: 10.3390/ma18092164.
The aim of this study was to compare the dimensional accuracy of vinyl polysiloxane impressions differing in terms of curing time (regular-setting (RS) or fast-setting (FS)) in combination with different tray materials (metal (M) and plastic (P)). A typodont reference model simulated a partially edentulous maxilla. Reference points were given by center points of either precision balls welded to specific teeth or finishing-line centers of prepared teeth. These reference points enabled the detection of dimensional deviations between the digitized reference and the scans of the models achieved from the study impressions. Twenty impressions were made for each of the following four test groups: RS-M, RS-P, FS-M and FS-P. Global scan data accuracy was measured by distance and tooth axis deviations from the reference, while local accuracy was determined based on the trueness and precision of the abutment tooth surfaces. Statistical analysis was conducted using ANOVA accompanied by pairwise Tukey post hoc tests (α = 0.05). Most of the distances tended to be underestimated. Global accuracy was favorable; even for long distances, the mean absolute distance deviations were < 100 µm. Local accuracy was excellent for all test groups, with trueness ≤ 11 µm and precision ≤ 9 µm. Within the limitations of this study, all impression and tray materials were suitable to fabricate models with clinically acceptable accuracy.
本研究的目的是比较在固化时间方面存在差异（常规固化（RS）或快速固化（FS））的乙烯基聚硅氧烷印模与不同托盘材料（金属（M）和塑料（P））组合的尺寸精度。一个典型牙列参考模型模拟了部分无牙的上颌骨。参考点由焊接到特定牙齿上的精密球的中心点或预备牙齿的龈缘线中心给出。这些参考点能够检测数字化参考与从研究印模获得的模型扫描之间的尺寸偏差。对以下四个测试组中的每一组制作20个印模：RS-M、RS-P、FS-M和FS-P。通过与参考的距离和牙轴偏差来测量全局扫描数据精度，而局部精度则基于基牙牙面的真实性和精确性来确定。使用方差分析并伴随两两Tukey事后检验（α = 0.05）进行统计分析。大多数距离往往被低估。全局精度良好；即使对于长距离，平均绝对距离偏差也<100 µm。所有测试组的局部精度都非常出色，真实性≤11 µm，精确性≤9 µm。在本研究的局限性范围内，所有印模和托盘材料都适合制作具有临床可接受精度的模型。
