Ji Jianhua, Wei Luming, Zha Xuzhe, Guo Huiying, Wang Penglai
Department of Implantology, Suzhou Stomatological Hospital, Suzhou, China.
School of Stomatology, Xuzhou Medical University, 209 Tongshan Road, Xuzhou, 221004, PR China.
BMC Oral Health. 2025 May 14;25(1):720. doi: 10.1186/s12903-025-06068-1.
Intraoral scanners (IOS) facilitate dental treatment, but the efficacy in full-arch scanning remains controversial. The aim of this study was to compare arch deformations between conventional impressions (CIs) and digital impressions (DIs) across six distinct spans in the maxillary and mandibular models, using the absolute linear deviation method.
Standard maxillary and mandibular models, each with seven cylindrical landmarks added, were used as the reference. CIs and DIs as test scans (n = 15 each) were performed on the models using silicone impression material and three IOSs: CS3600, Trios3, and Trios5. The trueness of the distances and angles between the remaining cylinders and initial scanning cylinder were evaluated. Data were analyzed using the Kruskal-Wallis and One-way ANOVA tests, with the Bonferroni test for post hoc analysis (α = 0.05).
Deviations of DIs increased gradually from smaller spans to full-arch spans, while deviations of CIs remained stable. Within a 5-tooth-units, DIs provided superior trueness compared to CIs (P < 0.05), except for ΔL8, where the results from four impression methods were comparable (P = 0.28). For other measurements, CIs exhibited significantly better trueness than three IOSs (P < 0.05).
The current accuracy of IOSs was insufficient for full-arch applications, but suitable for short scan ranges (fixed prostheses within a 5-unit span).
口腔内扫描仪（IOS）有助于牙科治疗，但全牙弓扫描的效果仍存在争议。本研究的目的是使用绝对线性偏差方法，比较上颌和下颌模型中六个不同跨度的传统印模（CI）和数字印模（DI）之间的牙弓变形情况。
使用标准的上颌和下颌模型，每个模型添加七个圆柱形标记作为参考。使用硅橡胶印模材料和三种IOS（CS3600、Trios3和Trios5）对模型进行CI和DI作为测试扫描（各n = 15）。评估剩余圆柱体与初始扫描圆柱体之间距离和角度的准确性。数据采用Kruskal-Wallis和单因素方差分析进行分析，并采用Bonferroni检验进行事后分析（α = 0.05）。
DI的偏差从较小跨度到全牙弓跨度逐渐增加，而CI的偏差保持稳定。在5个牙单位范围内，DI比CI具有更高的准确性（P < 0.05），除了ΔL8，四种印模方法的结果相当（P = 0.28）。对于其他测量，CI比三种IOS表现出明显更好的准确性（P < 0.05）。
IOS目前的准确性不足以用于全牙弓应用，但适用于短扫描范围（5单位跨度内的固定修复体）。
