Department of Mechanical Engineering, Shiraz University, Shiraz, Iran.
Dental Sciences Research Center, Department of Periodontics, School of Dentistry, Guilan University of Medical Sciences, Rasht, Iran.
Oral Surg Oral Med Oral Pathol Oral Radiol. 2021 Dec;132(6):735-743. doi: 10.1016/j.oooo.2021.03.012. Epub 2021 Mar 28.
The objective was to assess the effects of object position, field of view (FOV) size, peak kilovoltage (kVp), and a metal artifact reduction (MAR) algorithm on metal artifacts in cone beam computed tomography (CBCT) as measured with an auto-edge counting method.
A titanium implant and a stainless steel intracanal post in a root were inserted in bovine rib blocks. CBCT scans were acquired with changes in object position (incisor, canine, and premolar-molar areas), FOV, kVp, and MAR (on or off) mode. Images were quantitatively analyzed in MATLAB by using the Canny edge detection algorithm. Four-way analysis of variance and Tukey tests were applied for data analysis.
The implant produced no significant differences in number of artifacts among the object positions through changing the kVp and MAR mode for all FOV sizes (P > .05). The intracanal post scanned with the medium-sized FOV, high kVp, and MAR off mode generated significant differences among object positions (P = .033). Among the variables assessed, FOV size and MAR mode had a significant influence on the number of artifacts (P ≤ .039).
Reduction of FOV size and application of the MAR tool significantly decreased the number of streak artifacts. The Canny edge detection algorithm could be an efficient method of metal artifact quantification.
本研究旨在使用自动边缘计数法评估物置、视野(FOV)大小、峰值千伏(kVp)以及金属伪影减少(MAR)算法对锥形束 CT(CBCT)中金属伪影的影响。
将钛植入物和不锈钢根管内桩插入牛肋骨块中。通过改变物置(切牙、尖牙和前磨牙-磨牙区)、FOV、kVp 和 MAR(开或关)模式来获取 CBCT 扫描。使用 Canny 边缘检测算法在 MATLAB 中对图像进行定量分析。采用四因素方差分析和 Tukey 检验进行数据分析。
在改变所有 FOV 大小的 kVp 和 MAR 模式时,植入物在物置之间的伪影数量没有显著差异(P >.05)。在中等 FOV、高 kVp 和关闭 MAR 模式下扫描的根管内桩在物置之间产生了显著差异(P =.033)。在所评估的变量中,FOV 大小和 MAR 模式对伪影数量有显著影响(P ≤.039)。
减小 FOV 大小和应用 MAR 工具可显著减少条纹伪影数量。Canny 边缘检测算法可能是一种有效的金属伪影量化方法。