Zarone Fernando, Ruggiero Gennaro, Russo Lucio Lo, Mastrosimone Annamaria, Sorrentino Roberto
Department of Neurosciences, Reproductive and Odontostomatological Sciences, Division of Prosthodontics, Scientific Unit of Digital Dentistry, University "Federico II" of Naples, Naples, Italy.
Department of Neurosciences, Reproductive and Odontostomatological Sciences, Division of Prosthodontics, Scientific Unit of Digital Dentistry, University "Federico II" of Naples, Naples, Italy.
J Dent. 2025 Feb;153:105492. doi: 10.1016/j.jdent.2024.105492. Epub 2024 Nov 29.
This study evaluated the accuracy of the Medit i700 intraoral scanner (IOS) in capturing horizontal tooth preparations at different depths below the gingival margin and assessed its ability to detect surfaces beyond the finish line.
Using CAD software, two abutments of a standard maxillary first molar were designed with horizontal preparation and 0.8 mm chamfer at 1 mm and 2 mm depths below the gingival margin. The abutment designs, created in DentalCAD 3.0 Galway (Exocad), were 3D printed and mounted on a typodont with simulated pink gum. An experienced operator conducted 20 scans, with each scan taking between 1 and 2 min. The scanning process began at the occlusal surface of the right third molar and proceeded longitudinally to the contralateral molar, then extended buccally and palatally, resulting in two experimental groups: H-1 (1 mm depth) and H-2 (2 mm depth). Accuracy was assessed using Geomagic Control X software, with descriptive statistics and independent sample tests (α = 0.05) employed for group comparisons.
No statistically significant difference was found in trueness between H-1 and H-2 (p=.053). However, precision differed significantly (p<.001). The IOS could not capture surfaces beyond the finish line in horizontal preparations.
Within study limitations, the horizontal preparation design hindered the IOS's ability to capture tooth anatomy beyond the finish line. Nonetheless, accuracy values at both 1 mm and 2 mm depths were clinically acceptable.
CLINICAL SIGNIFICANCE,: The present study shows that the tested intraoral scanner is accurate enough to scan abutments with horizontal margins placed 1 and 2 mm below the gingiva.
本研究评估了Medit i700口内扫描仪（IOS）在获取龈缘以下不同深度的水平牙体预备时的准确性，并评估了其检测超出完成线表面的能力。
使用CAD软件，设计了标准上颌第一磨牙的两个基牙，在龈缘以下1mm和2mm深度处进行水平预备并带有0.8mm的倒角。在DentalCAD 3.0 Galway（Exocad）中创建的基牙设计进行3D打印，并安装在带有模拟粉色牙龈的牙模型上。一名经验丰富的操作员进行了20次扫描，每次扫描耗时1至2分钟。扫描过程从右侧第三磨牙的咬合面开始，纵向延伸至对侧磨牙，然后向颊侧和腭侧扩展，从而形成两个实验组：H-1（1mm深度）和H-2（2mm深度）。使用Geomagic Control X软件评估准确性，采用描述性统计和独立样本检验（α = 0.05）进行组间比较。
H-1组和H-2组在准确性方面未发现统计学上的显著差异（p = 0.053）。然而，精密度存在显著差异（p < 0.001）。IOS无法捕捉水平预备中超出完成线的表面。
在研究局限性范围内，水平预备设计阻碍了IOS捕捉超出完成线的牙齿解剖结构的能力。尽管如此，1mm和2mm深度处的准确性值在临床上是可接受的。
本研究表明，所测试的口内扫描仪足够准确，能够扫描龈缘以下1mm和2mm处带有水平边缘的基牙。
