Provedel Leonardo Francisco, Pimentel Bruna Natália Alves da Silva, Jesus Tarcísio Martins de, Lacerda Ana Paula Souza, Rubira-Bullen Izabel Regina Fischer, Sarmento Viviane Almeida
Dental School, UFBA - Universidade Federal da Bahia, Salvador, BA, Brazil.
Bauru Dental School, USP - Universidade de São Paulo, Bauru, SP, Brazil.
Braz Dent J. 2016 Oct-Dec;27(6):757-760. doi: 10.1590/0103-6440201601157.
This study aimed to evaluate the accuracy of panoramic radiographs obtained by digital system based on charge coupled device (CCD) and a phosphor storage plate (PSP) system with two different file formats, JPEG irreversible type and BMP. Linear measurements of artificial bony defects were made in dry mandibles with a digital caliper. Measures of digital panoramic radiographs were taken in ImageJ(r) software. Each measurement was performed twice by an experienced examiner. The intra-rater agreement was considered very strong (Pearson's correlation coefficient of 0.97). There was no significant difference between the linear measurements of dry mandibles, considered the gold standard, in relation to measurements obtained from digital radiographs (p=0.47). The error of these measures for the CCD was 1.04 mm (9.97%) for JPEG images and 1.03 mm (9.99%) for those with BMP format. For the PSP images, these values were 1.48 mm (14.94%) and 1.43 mm (14.43%), respectively. Although there was no statistical difference between the images with JPEG and BMP format, for both digital systems (p=1.00 for CCD and p=0.98 for PSP system), errors made on radiographs obtained by PSP system were significantly higher than those of CCD (p<0.05). The size of the files saved in JPEG was also significantly lower (p=0.005) compared with the files saved in BMP. It may be concluded that the digital radiographs, both saved in JPEG and BMP formats, are accurate, regardless the used digital system, and JPEG images are more suitable for teleradiology.
本研究旨在评估基于电荷耦合器件（CCD）的数字系统和具有两种不同文件格式（JPEG不可逆类型和BMP）的磷光存储板（PSP）系统所获得的全景X线片的准确性。使用数字卡尺对干燥下颌骨中的人工骨缺损进行线性测量。在ImageJ(r)软件中对数字全景X线片进行测量。每项测量由一位经验丰富的检查者进行两次。检查者内一致性被认为非常强（Pearson相关系数为0.97）。与作为金标准的干燥下颌骨的线性测量相比，从数字X线片获得的测量结果无显著差异（p = 0.47）。对于CCD，JPEG图像的这些测量误差为1.04 mm（9.97%），BMP格式图像的误差为1.03 mm（9.99%）。对于PSP图像，这些值分别为1.48 mm（14.94%）和1.43 mm（14.43%）。尽管JPEG和BMP格式的图像之间没有统计学差异，对于这两种数字系统均如此（CCD的p = 1.00，PSP系统的p = 0.98），但PSP系统获得的X线片上的误差显著高于CCD的误差（p < 0.05）。与以BMP格式保存的文件相比，以JPEG格式保存的文件大小也显著更小（p = 0.005）。可以得出结论，无论使用哪种数字系统，以JPEG和BMP格式保存的数字X线片都是准确的，并且JPEG图像更适合远程放射学。
