Notes:

a. CCD (Charge-Coupled Devices) technology, same as the one used in digital photo cameras, but requiring a lot larger sensors. It is expensive, but very stable and reliable. The two inventors of the CCD, among which one is Canadian, were awarded the Nobel Prize for Physics in 2009. Using this technology for taking X-rays requires a scintillation plate inside the sensor, which reduces slightly the quality of the image.

b. Cadmium - Tellurium technology is new and reliable but rather expensive. It does not require a scintillation plate, but requires instead many electronics, resulting in a larger sensor.

c. CMOS technology - less expensive, but also delivers lower quality pictures. It also requires a scintillation plate inside the sensor.

d. PSP technology - film like (a lot thicker) phosphor plates. Unlike films, will not require chemicals for processing, but will require a special, expensive scanner to read the image from the plates. Time to read the plate depends on the size and the resolution and may go up to tens of minutes for highest quality images. Also, there is a recurring cost for changing the phosphor plates and the sleeves after a certain number of exposures.

1. The picture quality looks better with Tl-Cd Sensors, and good with CCD and PSP. Both the choice of CMOS technology and the design employed in the retrofit kit from Schick lead to the result that that the quality and the geometry of its X-ray images is not as good and stable as with the other systems.
2. Only DXIS will reduce the radiation, by replacing the primary slot surface with a new slot. Depends on the Pan model to be retrofitted to Digital, the reduction is between 30 to 70%). All the others will use the same device as the one used for films, meaning the same radiation level for the patients. The rotation time cannot be reduced and the KVp also (the KVp level is dependent of the size of the patient head - bigger head - more kVp is required).
3. Sensor size is important for the visibility required to position the patient properly, which is very important in order to obtain good pictures.
4. As this technology uses a scanner, the size of the phosphor plates used for taking X-rays is the same as for films. Consumables still required (phosphorus plates, sleeves etc ) .
5. It is preferable to have less wires and connectors, as this means a more reliable system.
6. The presence of an AC/DC adaptor may lead to possible electrical noise interference with the picture. A battery is the best solution as it does not produce interference, it is not expensive, but will have to be replaced each 4-5 years. Among the systems tested, only DXIS uses a battery.
7. See the retrofit systems available for different models of Panoramic X-ray machines in the annex.
8. A smaller pixel size is the preferable.
9. Date when the system was first available on the market.
10. Desirable feature. Seeing the picture during the rotation of the arm will prevent an all-too often seen and very unpleasant situation - a patient is fully exposed to X-ray (12 to 18 seconds), but no picture is produced at the end, due to wrong settings being used, or no film being loaded. With the “real time” feature, should any error occur, the operator can stop the exposure after only 2-3 second, and do the necessary correction. This feature prevents patient frustration over being doubly exposed to radiation.
11. More lines pairs of the image, better picture quality.
12. By removing the old film mechanism (Cassette or film drum, plus all the belts, motors, sensors etc) a lot of sources of malfunctions will be prevented, and consequently the usable life of the machine is increased. The conversion from film to digital will be permanent with AJAT and DXIS systems (or very time consuming to reverse back to film), and very easy with the Schick system. With PSP there is not any change at all - the machines will operate exactly in the same ways as with film.
13. The biggest (and only) advantage of PSP systems over the direct digital systems is the availability of the CEPH option. For the Pan - Ceph machines, the Ceph part cannot be converted to digital as of now because of the high cost of the sensors, and in the case of the DXIS and AJAT systems, the Ceph will not be usable after the conversion, not even with films.
14. It is an extra safety features. In some US states it is forbidden for an equipment to emit radiations to the patients if there is no (for different reasons) acquisition of the picture.
15. Only AJAT has this feature - if a part of the x-ray is not on focus (blurry part of the picture) the software has the possibility to move back or forward between the layers, so that the blurry part of the picture becomes useable.
16. The DXIS is the best with this respect. The AJAT the worst.
17. Real time speed does not exist per see, as a delay of 2 seconds exists even with the DXIS and AJAT systems. The 2-seconds delay appears when transferring the large panoramic image to the computer. With the Schick system the picture will be seen after the end of the arm rotation. With the PSP the time it is almost the same as with films.
18. It was the European Medical Society belief that the Tyroid Gland and the Optic Nerve should not be exposed to X-ray radiation. That’s why the DXIS sensor is 12,7 cm and the others (USA manufactured or for USA use) are 15.00 cm width. A lot of European Pan models are using 12,7 cm films. By proper positioning (head up or down on the chin rest) the TMJ or the complete chin will be seen on the picture.
19. Depends on the Pan Model.
20. The price depends on the complexity of the retrofit system. These are approximate figures.

Note: This is an attempt to present the differences between the different systems at the best of our knowledge. Any observations and addition to this comparison is very well welcome. Please send your observations to alex@panrad.com Thank you!

1. The DXIS System is compatible with the following 21 machines:

PC1000 Panoramic Corporation	PROLINE 2002 EC and CC Planmeca	ROTOGRAPH Plus and 230 Villa Sistemi Medicali	PANTOS Bluex	ARCOGRAPH Imago	PANOURA ULTRA, 10 & 12 Yoshida	ORTHORALIX SD Gendex
GX-PAN Gendex	OP5 Siemens	OP10 Siemens	ORTHOPHOS PLUS Sirona	ORTHOPHOS 3 and 5 Sirona	AVANTEX BMT	PANELIPSE 1976+, I & II

2. The AJAT System (SCAN 300 FP) is compatible with the following 7 machines:

3. The Schick System (iPan) is compatible with the following 10 machines