Comparison of endodontic measurement controls using a paralleling technique with a grid and a conventional measurement.

Pretreatment radiographs were taken using a paralleling device and measurement grid. The measurement controls obtained in that manner in 60 teeth were compared to measurements obtained from conventional radiographs taken during endodontic treatment. This study was undertaken to test the proposal that pretreatment radiographs taken with a paralleling device and measurement grid would make further radiographs for that purpose unnecessary, thus reducing patients' exposure to ionizing radiation.