Potential of a New Cone-Beam CT Software for Blooming Artifact Reduction

Abstract This study evaluated the dimensions of intraradicular posts using a new cone beam CT (CBCT) software, and verified the potential of blooming artifact reduction. Sixty-three single-rooted human teeth were shaped, obturated, prepared for intracanal post placement and distributed into three groups: G1: anatomically customized prefabricated glass fiber posts; G2: low-fusion alloy posts; G3: gold alloy posts. After post fabrication and luting with RelyX U200®, specimens were sectioned axially at 9 mm from the root apex, and markings were made on the root surfaces (X-, Y- and Z-axes). The dimensions of the original posts (control group) were measured using a digital micrometer. CBCT scans of the teeth were obtained using a PreXion 3D Elite® scanner. Posts were measured on CBCT scans using DICOM files and the e-Vol DX software. A specific filter, Blooming Artefact Reduction (BAR), was developed to analyze intracanal posts. Statistical data were evaluated using the Van de Waerden nonparametric analysis of variance and, after that, normalized data were analyzed using the Tukey test. The level of significance was set at α = 5%. The measures of the anatomical prefabricated, low-fusion alloy and gold alloy intracanal posts obtained using the e-Vol DX CBCT software and a micrometer were not significantly different (p>0.05). The use of the BAR filter of the e-Vol DX software application did not induce any dimensional differences on CBCT scans of intracanal posts when compared with measurements made with a micrometer on original posts. The use of the BAR filter eliminated blooming artifacts.摘要 本研究利用一款新型锥形束计算机断层扫描（cone beam CT, CBCT）软件评估了根管内桩（intraradicular post）的尺寸，并验证了其抑制晕状伪影的应用潜力。本研究选取63颗单根人牙，经根管成形、根管充填、根管桩就位预备后分为三组：G1组：解剖个性化预制玻璃纤维桩；G2组：低熔合金桩；G3组：金合金桩。完成桩体制作并采用RelyX U200®粘接剂粘接固定后，将标本于距根尖9 mm处轴向截断，并在牙根表面标记X、Y、Z轴坐标系。采用数字千分尺测量原始桩体（对照组）的尺寸。使用PreXion 3D Elite®扫描仪获取牙齿的CBCT扫描影像。通过DICOM文件与e-Vol DX软件对CBCT扫描影像中的桩体进行尺寸测量。本研究开发了一款专用滤波器——晕状伪影减少（Blooming Artefact Reduction, BAR），用于分析根管内桩。统计学分析先采用Van de Waerden非参数方差分析，随后对正态化数据采用Tukey检验进行分析，显著性水平设定为α=5%。结果显示，利用e-Vol DX CBCT软件与千分尺测得的解剖个性化预制桩、低熔合金桩及金合金根管内桩的尺寸无显著差异（p>0.05）。与原始桩体经千分尺测量的结果相比，使用e-Vol DX软件的BAR滤波器并未对根管内桩的CBCT扫描影像测量结果引入尺寸偏差。BAR滤波器可有效消除晕状伪影。