31 October 1997, Volume 26, Issue 6, Pages 337 – 343

Paper

Impact of scale standardization on images of digital radiography systems CH Versteeg1, GCH Sanderink, WGM Geraets & PF van der Stelt Department of Oral Radiology, Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands     1Author for correspondence Present address: Department of Oral Radiology, Louwesweg 1, 1066 EA Amsterdam, The Netherlands

Keywords

radiography, dental;   imaging processing, computer-assisted;   diagnostic imaging

Abstract

Objectives: To test the effect of altering image size on diagnostic quality. Methods: Endodontic files, size 10 and 15 were prepared to full root length and 1.5 mm short, in upper and lower molars and premolars. Digital images of the Sidexis (S) and Visualix/Vixa (V) system were reduced in size to Digora (D) scale, and the D images were enlarged to S scale. ROC analysis was performed and data analysed with MANOVA statistics. Results: Assessment of root canal length with file size 10 was less accurate for the S images reduced in size, compared with the original S images (P<0.011). All other differences were not significant (P>0.081). Conclusions: Relevant diagnostic information may be lost when images are reduced in size. Therefore, for optimal presentation, the smaller images should be enlarged rather than the larger ones reduced.

Received 25 March, 97; Accepted 16 June, 97

^© Macmillan Publishers Ltd 1997