Tube angulation effect on radiographic analysis of the implant-abutment interface.

The purpose of this study was to determine the maximum permissible x-ray tube angulation that can be used to verify the fit of an abutment. An implant and an abutment were assembled with an abutment screw. A variety of openings were created between the abutment and the implant. Radiographs were taken combining the different gaps with various x-ray tube angulations. The radiographs were randomly presented to 8 clinicians, who judged the interface as open or closed. The results indicate that a radiographic analysis of interface openings becomes subjective with tube angulations of more than 5 degrees.