BACKGROUND AND OBJECTIVE: The use of dental radiography is inevitable in order for disease diagnosis, assessment and monitoring. Radiogeraphy is potentially harmful due to the use of ionizing radiation. This study was conducted to evaluate dentists’ knowledge about the principles of dental radiology.

 METHODS: This cross-sectional study was performed on 600 general dentists willing to cooperate with this study in Amol, Noor, Mahmoodabad and Sari cities located in Mazandaran province, Iran, in 2014. All the data were obtained by means of a questionnaire. The questionnaire included two parts the first part surveyed demographic information, and the second part included 11 items about radiographic technique and equipments.

FINDINGS: 500 questionnaires were completed. Among the surveyed population, 335 (67%) and 165 (33%) dentists were male and female, respectively. The mean of practical experiences was 12.35±6.68 years. 469 dentists (93.8%) used the dental X-ray machine with digital timer and 404 dentist (80.8%) used the dental X-ray machine with long cone tube. Additionally, 470(94%) X-ray machine had round. Generally, 367 (73.4%) and 374 (74.8%) dentists used bisecting technique and E-speed films, respectively. Also, annual calibration of X-ray devices was suggested by 416 (83.2%) dentists.

CONCLUSION: According to our study, dentists’ knowledge about the dental radiography principles was fair.