Department of Restorative Dentistry, National Dental Centre of Singapore, Singapore, Republic of Singapore.
Faculty of Dentistry, National University of Singapore, Singapore, Republic of Singapore.
J Prosthodont. 2024 Jan;33(1):46-53. doi: 10.1111/jopr.13647. Epub 2023 Feb 2.
To study the effect of implant angulation on 3D linear and absolute angular distortions of implant analogs in printed resin models and conventional stone casts.
Three sectional master models with two implants with total inter-implant angulations of 0°, 10°, and 20° were fabricated. For each master model, five conventional stone casts (CS) and printed resin models (PM) were fabricated (n = 5). Test models were made with nonsplinted impression copings and open tray polyether impressions for the CS groups and scan bodies scanned using an intraoral scanner for the PM groups. The physical positions of the implants and implant analogs were measured with a coordinate measuring machine. 3D linear distortion (ΔR) and absolute angular distortion (Absdθ) defined the 3D positional accuracy of the analogs in the test models. Univariate ANOVA was used to analyze data followed by post hoc tests (Tukey HSD, α = 0.05).
Mean ΔR was significantly greater for PM10 (73.5 ± 8.9 µm) and PM20 (65.5 ± 33.3 µm) compared to CS0 (16.8 ± 14.1 µm), CS10 (22.2 ± 13.0 µm), CS20 (15.6 ± 19.9 µm), and PM0 (23.9 ± 16.1 µm). For Absdθ, there were no significant differences between test groups.
With conventional stone casts, implant angulation had no significant effect on 3D linear and absolute angular distortions. Amongst printed resin models test groups, angulated implants had significantly greater ΔR. Amongst angulated implants test groups, printed resin models had significantly greater ΔR than conventional stone casts. Compared to the master model, all test groups, regardless of inter-implant angulation, produced greater inter-analog distances.
研究种植体角度对印模模型和常规石膏模型中种植体模拟三维线性和绝对角度偏差的影响。
制作三个带有两段种植体的分段主模型，两段种植体的总种植体间角度分别为 0°、10°和 20°。对于每个主模型，分别制作五个常规石膏模型（CS）和五个打印树脂模型（PM）（n=5）。CS 组使用无支架印模帽和开放式托盘聚醚印模制取测试模型，PM 组使用口内扫描仪扫描扫描体制取测试模型。使用坐标测量机测量种植体和种植体模拟体的物理位置。三维线性偏差（ΔR）和绝对角度偏差（Absdθ）定义了模拟体在测试模型中的三维位置精度。采用单因素方差分析对数据进行分析，然后进行事后检验（Tukey HSD，α=0.05）。
PM10（73.5±8.9μm）和 PM20（65.5±33.3μm）的平均 ΔR 明显大于 CS0（16.8±14.1μm）、CS10（22.2±13.0μm）、CS20（15.6±19.9μm）和 PM0（23.9±16.1μm）。对于 Absdθ，各组之间无显著性差异。
对于常规石膏模型，种植体角度对三维线性和绝对角度偏差无显著影响。在打印树脂模型测试组中，倾斜种植体的 ΔR 明显更大。在倾斜种植体测试组中，打印树脂模型的 ΔR 明显大于常规石膏模型。与主模型相比，所有测试组，无论种植体间角度如何，都产生了更大的模拟体间距离。
