Department of Oral Diagnosis, Division of Oral Radiology, State University of Paraíba, Campina Grande, Brazil.
Department of Integrative Biomedical & Diagnostic Sciences, School of Dentistry, Oregon Health & Science University, Portland, USA.
Dentomaxillofac Radiol. 2021 Sep 1;50(6):20200563. doi: 10.1259/dmfr.20200563. Epub 2021 Feb 10.
To assess the influence of field of view (FOV) size, scanning position within the FOV and scanning mode on the detection of root fracture and artifact perception.
Forty single-rooted premolars restored with NiCr and AgPd posts were divided into two groups: fractured and sound. All teeth were scanned using four CBCT scanning protocols varying FOV sizes (80 × 80 mm and 50 × 55 mm) and scanning modes (Standard and High Definition). The sample was positioned within the FOV in two pre-set positions (central and lateral) and in four positions established by the operator (quadrants). Detection of root fracture and artifact perception were assessed by two observers using 5-point and 4-point scales. Sensitivity, specificity, accuracy, and AUC values were calculated and compared by ANOVA two-way and Tukey's test. Chi-square and Fisher's exact test were used to assess artifact perception. The level of significance was set at p < 0.05.
The central position within the FOV presented higher sensitivity, specificity, accuracy, and AUC values and differed from the lateral position within the FOV for the studied metal posts (p<0.05). Quadrant 2 presented the best sensitivity, accuracy, and AUC values (p<0.05). The lateral position within the FOV, AgPd posts, quadrants 1 and 3 and protocols 1 (SM, 80 × 80) and 2 (HD, 80× 80) presented higher frequency of artifacts classified as "severe".
Positioning the object in the center or closer to the anterior periphery of the FOV while using a small FOV improved the detection of root fracture and decreased artifact perception.
评估视野（FOV）大小、FOV 内扫描位置和扫描模式对根折检测和伪影感知的影响。
将 40 颗用 NiCr 和 AgPd 桩修复的单根前磨牙分为骨折组和正常组。所有牙齿均使用四种 CBCT 扫描方案进行扫描，FOV 大小（80×80mm 和 50×55mm）和扫描模式（标准和高清）不同。将样本放置在 FOV 内的两个预设位置（中央和侧方）和操作员设定的四个位置（象限）。两名观察者使用 5 分制和 4 分制评估根折和伪影感知。通过方差分析双向和 Tukey 检验计算和比较灵敏度、特异性、准确性和 AUC 值。使用卡方和 Fisher 精确检验评估伪影感知。显著性水平设为 p<0.05。
FOV 中央位置的灵敏度、特异性、准确性和 AUC 值较高，与 FOV 侧方位置不同，研究中的金属桩也如此（p<0.05）。象限 2 具有最佳的灵敏度、准确性和 AUC 值（p<0.05）。FOV 侧方位置、AgPd 桩、象限 1 和 3 以及方案 1（SM，80×80）和 2（HD，80×80）的伪影感知率较高，被归类为“严重”。
在使用小 FOV 时，将物体放置在中心或更靠近 FOV 的前侧边缘，可以提高根折的检测率，降低伪影感知。
