New approach to analysis of rotational panoramic radiography by computer simulation.

Computer simulation is an effective method for mathematical analysis of the image of rotational panoramic radiography. Conventional simulation methods have been used only for analysis of imaging factors and prediction of the characteristics of the obtained image. This paper describes a new computer simulation method that analyzes the imaging factors and produces the simulated image itself. The simulation is carried out by reproducing the actual image formation process in the computer. The head phantom for simulation, which represents the human dentomaxillofacial structures as a numerical value from 0 to 4, was constructed by scanning a real head phantom from neck to head with an X-ray CT scanner at a slice thickness of 1 mm and at 1 mm slice intervals. The diverging X-ray beam was expressed as a set of straight lines and was moved according to various parameters. The simulated image obtained was satisfactory for image analysis of rotational panoramic radiography.