RVG sensors and film: what actually changes in the surgery

Most comparisons of digital sensors and film start with resolution, which is odd, because resolution is not what makes a practice change over. Film resolves beautifully. What it does not do is give you the image while the patient is still in the chair with a rubber dam on.

The chairside minutes

A film exposure is followed by a walk, a wait, chemistry and a return. Six to ten minutes, and the patient sits through all of it. An RVG sensor puts the image on the monitor in about two seconds, which changes three things in the same appointment:

• Retakes stop costing anything. A bad angle is discovered immediately, not after processing, so the retake happens while the patient is already positioned.
• Working films become practical. Mid-treatment checks during endodontics stop being a decision about time and start being routine.
• The consultation happens at the chair. You can point at the lesion on a screen the patient is already looking at. Case acceptance is a conversation, and this is the part of the appointment where it happens.

Dose

A digital sensor needs a fraction of the radiation film does for a diagnostic image, because the sensor is more sensitive than an emulsion. That is worth stating plainly to patients, and worth checking on any unit you are offered: the number should appear in the specification, not in a sales conversation.

What it costs you to keep running

Film has a recurring bill that never ends: the film itself, the chemistry, the mounts, the processor's maintenance and the disposal of fixer, which is a regulated waste. A sensor has a purchase price and then, in practice, a cable.

That is the real financial shape of the decision. Film is cheap to start and expensive forever; a sensor is the reverse. Most practices we work with pass the crossover somewhere in the second year.

The failure mode nobody mentions

Sensors do not fail from imaging. They fail from cables and from being dropped. When you compare units, compare those two things:

• Is the cable replaceable on its own, or does a damaged cable mean a new sensor?
• What is the drop rating, and what does the warranty say about accidental damage as opposed to defects?
• How long is a repair, and is there a loan unit while you wait?

A sensor that images marginally better but is out of the practice for three weeks after a fall is the worse machine.

Fitting it to what you already have

A sensor is only as useful as the software it lands in. Before buying, check that the images arrive in the practice management system you already use rather than in a separate viewer somebody has to remember to open, and that every chair which needs the images can see them.

Our intraoral range and the software it runs in are on the products page, and if you would like to see one in the surgery rather than in a brochure, a demonstration is free and takes about half an hour.