Clinic for Orthodontics and Pediatric Dentistry, Center of Dental Medicine, University of Zurich, and Department of Diagnostic Imaging, University Children's Hospital Zurich, Plattenstrasse 11, 8032 Zurich, Switzerland.
Dentomaxillofac Radiol. 2012 Dec;41(8):637-44. doi: 10.1259/dmfr/21152480. Epub 2012 May 3.
The aim was to compare the accuracy of linear bone measurements of cone beam CT (CBCT) with multidetector CT (MDCT) and validate intraoral soft-tissue measurements in CBCT.
Comparable views of CBCT and MDCT were obtained from eight intact cadaveric heads. The anatomical positions of the gingival margin and the buccal alveolar bone ridge were determined. Image measurements (CBCT/MDCT) were performed upon multiplanar reformatted data sets and compared with the anatomical measurements; the number of non-assessable sites (NASs) was evaluated.
Radiological measurements were accurate with a mean difference from anatomical measurements of 0.14 mm (CBCT) and 0.23 mm (MDCT). These differences were statistically not significant, but the limits of agreement for bone measurements were broader in MDCT (-1.35 mm; 1.82 mm) than in CBCT (-0.93 mm; 1.21 mm). The limits of agreement for soft-tissue measurements in CBCT were smaller (-0.77 mm; 1.07 mm), indicating a slightly higher accuracy. More NASs occurred in MDCT (14.5%) than in CBCT (8.3%).
CBCT is slightly more reliable for linear measurements than MDCT and less affected by metal artefacts. CBCT accuracy of linear intraoral soft-tissue measurements is similar to the accuracy of bone measurements.
比较锥形束 CT（CBCT）与多排 CT（MDCT）的线性骨测量精度，并验证 CBCT 中口腔软组织的测量值。
从 8 个完整的尸体头颅中获得 CBCT 和 MDCT 的可比视图。确定牙龈缘和颊牙槽骨嵴的解剖位置。对多平面重建数据集进行图像测量（CBCT/MDCT），并与解剖测量值进行比较；评估无法评估的部位数量（NAS）。
放射学测量值准确，与解剖测量值的平均差异为 0.14mm（CBCT）和 0.23mm（MDCT）。这些差异在统计学上无显著性意义，但骨测量的一致性界限在 MDCT 中更宽（-1.35mm；1.82mm），而在 CBCT 中较窄（-0.93mm；1.21mm）。CBCT 中软组织测量的一致性界限较小（-0.77mm；1.07mm），表明准确性略高。MDCT 中出现的无法评估部位数量（14.5%）多于 CBCT（8.3%）。
与 MDCT 相比，CBCT 更可靠用于线性测量，且受金属伪影的影响较小。CBCT 对口腔内线性软组织测量的准确性与骨测量的准确性相似。
