Comparison of periapical and detailed narrow-beam radiography for diagnosis of periapical bone lesions.

Abstract

The diagnostic performance of the detailed narrow-beam (DNB) technique of the Scanora multimodal radiography system was compared for periapical radiography for the detection of periapical bone lesions at 262 dental sites in 144 patients. Receiver operating characteristics (ROC) of both imaging modalities were analysed in relation to the ratings of five observers for the whole dentition, three dental regions, and two types of periapical lesions. ROC analysis demonstrated no overall or regional significant differences in the diagnostic performance of the two imaging modalities. The sensitivity for periapical radiography was 72% and for DNB radiography 90%, and the specificities 89% and 88%, respectively. It is concluded that DNB radiography performs as well as periapical radiography for detecting periapical bone lesions.

A comparison of detailed zonography with periapical radiography for the detection of periapical lesions.

“…For periapical radiography, our intra-observer agreement rates accord with those found in most previous studies 4 ' 21 ' 23 ' [25][26][27] . Intra-observer agreement rates for multiview and stereoscopic zonography were also slightly lower than those for multiview DNB radiography 4 . The difference might be explained by the fact that the observers were familiar with the DNB technique, because the imaging principle of DNB radiography is similar to panoramic radiography.…”

“…In detailed dento-alveolar imaging using the Scanora® unit, diagnostic information is gathered from each dental region selectively, using multiple projections and magnification. We found, in a previous study 4 , that detailed narrow-beam (DNB) radiography revealed 18% more periapical lesions than periapical radiography, when this technique was used to supplement the information obtained from a panoramic radiograph. In DNB radiography, tomographic blurring is achieved by rotational scanning, in zonography by using spiral movement 1 .…”

“…Periapical radiographs were taken as described elsewhere 4 , using a Minray DC X-ray unit (Soredex/ Orion Corp., Helsinki, Finland) and modified paralleling technique, and Ε-speed film (Eastman Kodak Co., Rochester NY, USA). Detailed zonography was performed using a Scanora® multimodal X-ray unit (Soredex/Orion Corp., Helsinki, Finland) with a fourturn spiral movement and a 2° exposure angle.…”

“…Resolution was 4.2 lp mm -2 ( Figure 1). All films were developed using automatic processing, as described previously 4 .…”

“…After one month, the assessments were repeated by the same observers using half of the same series of images, to test intra-observer variation. The reading protocol and viewing procedure for the images have been described elsewhere 4 . Stereoscopic viewing of zonograms was performed using a stereoscope (Electromedizinische Werkstätte, Landau-Isar, Germany).…”