Comparison of technical errors in pediatric bitewing radiographs acquired with round vs rectangular collimation

Abstract

To compare technical errors in bitewing radiographs acquired with round vs rectangular collimation in a hospital-based pediatric dentistry training program. A retrospective chart review was conducted of 176 digital bitewing radiographs exposed with round collimation and 106 exposed with rectangular collimation. The number of re-exposures was calculated, and errors in central ray entry (CRE; "cone cuts"), horizontal and vertical positioning, and angulation were measured. There were no greater re-exposures but significantly more CRE errors with rectangular collimation (21.7%; n = 23; 95% confidence interval [CI], 13.9%-30.0%) than with round collimation (3.4%; n = 6; 95% CI, 0.7%-6.1%). CRE error location, horizontal positioning errors, and size of horizontal overlapped contacts were statistically different but not clinically important. Use of rectangular collimation resulted in increased CRE errors but no other clinically significant problems. This technique should be used to reduce radiation exposure to patients.