Sensitometric characteristics of dental xeroradiography

Dental xeroradiography is a high-quality intraoral imaging system which provides a potentially convenient, rapid, low-dose alternative to conventional film radiography. In this study the sensitometric properties of dental xeroradiography were investigated via assessment of high- and low-contrast xeroradiographic processor settings, transmission versus reflection densitometry, reciprocity-law failure, and kVp (tube voltage) plate dependence. Findings of the study indicated that imaging at high-contrast processor settings results in greater dynamic range but less exposure latitude than imaging at low-contrast processor settings. Determination of characteristic curves demonstrated greater contrast in reflection mode than imaging by transillumination for all but the very densest of images (greater than 1.6 O.D.). There was also little difference in characteristic curves produced from 50 to 90 kVp, indicating that the xeroradiographic plate exhibits a relatively constant sensitivity over the tube voltages tested if exposure is expressed in roentgens. Finally, no substantial reciprocity-law failure was observed for dental xeroradiography over a clinically relevant range of exposure times.