Dubrez B, Jacot-Descombes A, Pun T, Cimasoni G
University of Geneva, Switzerland.
Dentomaxillofac Radiol. 1992 Feb;21(1):40-4. doi: 10.1259/dmfr.21.1.1397451.
Photodensitometry is known to provide high spatial resolution and continuous measurement of optical density for the analysis of dental radiographs, whereas digitization allows powerful image manipulations but, when using conventional video cameras, gives less spatial resolution and fewer grey levels. The aim of this study was therefore to develop a technique of high-resolution digital analysis for the measurement of bone density following the same principles as those of photodensitometry and based upon the use of a CCD Scanner Camera which provides up to 4096 grey levels and a spatial resolution of 4096 x 4096 pixels. Twenty-four zones were analysed with both techniques in five serial dental radiographs taken before and after periodontal therapy in eight patients. Statistical comparison of the results obtained by digital analysis and photodensitometry shows that the two techniques have the same accuracy.
已知光密度测定法可提供高空间分辨率，并能对牙科X光片进行光密度的连续测量，而数字化则允许进行强大的图像处理，但是，使用传统摄像机时，其空间分辨率较低，灰度级也较少。因此，本研究的目的是开发一种高分辨率数字分析技术，用于测量骨密度，该技术遵循与光密度测定法相同的原理，并基于使用提供高达4096个灰度级和4096×4096像素空间分辨率的CCD扫描相机。在八名患者牙周治疗前后拍摄的五张连续牙科X光片中，对24个区域使用这两种技术进行了分析。对数字分析和光密度测定法所得结果的统计比较表明，这两种技术具有相同的准确性。
