Comparison of linear measurements made from storage phosphor and dental radiographs

Objectives. To compare linear measurements made from storage phosphor and dental radiographs. Methods. Five dry hemimandibles were imaged with an 8 x 10-inch (20.3/25.4 cm) high-resolution storage phosphor plate and Ektaspeed Plus occlusal-size dental film. Optimal exposure was empirically determined for the dental films. Reductions in exposure of 50 and 75% were used for the storage phosphor. Three observers made linear measurements between end-points of lines and center-points of fiducials on clinical specimens, dental radiographs, digitized dental radiographs and storage phosphor images. Data were analysed with repeated-measures and nested analysis of variance. Results. Measurements obtained from optimally exposed dental films and reduced-exposure storage phosphor images were equivalent to clinical measurements recorded from dry hemimandibles. Less than 2% of variation among measurements was attributable to the five modalities. Conclusion. No substantive difference was detected between linear measurements obtained from the storage phosphor or dental radiographs. Because storage phosphor images require no chemical processing, can be used at reduced exposure and are inherently digital, they are a viable alternative to dental film for making linear measurements. Copyright (C) 1996 Elsevier Science Ltd for IADMFR.