Long-cone parallel radiography is a requirement for endodontics, because it gives an undistorted view of the teeth and surrounding structures and is repeatable, thus allowing more accurate assessment of periapical healing. The bisecting angle technique should no longer be employed. It is further recommended that rectangular collimation be fitted on all new radiographic equipment, and retro-fitted to existing equipment as soon as possible. There are many beam-aiming devices available to hold the x-ray film parallel to the tooth. Figure 5 shows an example of a popular holder, with a special cage attachment to fit over a rubber dam clamp. 
A quick, reliable method of viewing radiographic images is essential for endodontics. Considerable time can be lost if such a system is not available, especially on those occasions when the exposed film does not show the required detail. Practitioners using conventional radiography may wish to purchase an x-ray film processor with rapid developing and fixing solutions, capable of producing a radiograph for viewing in under a minute; an example is shown in Figure 6. However, a modern automatic processor (Fig. 7) may be adjusted to deliver wet films in under two minutes. Films from both types of processor should be carefully dried after viewing for accurate storage in the patient s records. A modern alternative involves the use of digital radiography. A sensor plate, appropriately sterilized and sealed, is used in place of the conventional film. The sensor may be either directly linked to the computer, or resemble a conventional periapical film packet. The resultant image is digitally processed and projected upon the computer screen in a matter of seconds. The quality of the image can be manipulated to enable greater clarity when reading the picture. For purposes of record keeping, the image may be either dated, labelled and stored in the central database, or a hard copy printed for the patient s records. An example of such a system, and the images produced, is shown in Figure 8.
The pre-operative radiograph contains much information to assist the operator, which may not be seen if the film is carelessly viewed. An xray viewer and some form of magnification are needed to examine periapical films, and it is very helpful if glare from the light around the radiograph can be excluded (Fig. 9).
