Prevest Research Institute has a dental x-ray system model: ALERIO DC Prime High Frequency Dental X-ray System. Maximum output is 70kV, 8mA, exposure timer range 0.01s-5s; total filtration < 2mm Al, and X-ray beam size 60 mm at PID with a focal spot of 0.4mm IEC.
This is used in conjunction with films, digital sensor, phosphor plate and digital scanner for measuring radio-opacity of dental materials such as endodontic materials and polymer-based restorative materials according to ISO standards- such as ISO 6876 and ISO 4049. The analysis of radio-opacity is made by comparison with standard aluminium step wedge and grey scale image analysis. The value of radio opacity is usually expressed in mm as equivalent to aluminium.