How a 3D X-ray (DVT) appointment works, step by step

For an examination that produces this much anxiety in the waiting room, the 3D scan (DVT, digitale Volumentomographie) is remarkably undramatic. You stand or sit at an open device, rest your chin on a support, keep still while an arm travels once around your head, and the exposure is over in seconds. Nothing is injected, nothing is swallowed, there is no tunnel and no contrast agent. The images appear on screen within about a minute, and you can look at them straight away with the dentist. Afterwards there are no restrictions of any kind: you drive, eat, work and collect your children exactly as planned.

There is almost no preparation, which is the first surprise. You do not need to fast, you may drink coffee, and no medication needs to be paused. If seeing the machine in advance would settle your nerves, it is pictured on the 3D X-ray (DVT) – service page (EN).

Four things are genuinely worth doing.

Bring images you already have. A 3D data set or panoramic image from a previous practice — in Wuppertal, in Solingen, in Düsseldorf, or from the country you moved from — may make a new scan unnecessary. Request the DICOM files rather than a printout; only data can be measured and reassessed.

Write down what has already been imaged. Date, type, region, where it was taken. Hospital scans count too.

Say if you are pregnant or might be. Before planning, not at the machine. Nobody will ask you to explain the answer.

Leave heavy jewellery at home if you already know you are being scanned. It saves a small amount of fiddling at the device.

The scan does not begin with the machine. Under German radiation-protection law, a dentist with the required qualification (Fachkunde im Strahlenschutz) must first establish that this particular image is medically necessary — the so-called justifying indication (rechtfertigende Indikation). It is a legal step, not a formality, and it is the reason you cannot simply request a scan the way you request a cleaning.

In practice, that conversation covers four points: what the clinical question is, why a flat image cannot answer it, what has already been imaged, and what it costs. Since a 3D scan is a private service for statutory patients, you receive a written agreement to sign in advance — with us it is 178 €, and you hear that before anything is switched on.

This is the moment to ask anything you want to ask. Once the arm starts rotating, conversation is not an option.

Metal above the shoulders scatters X-rays and produces bright streaks in the reconstruction, which can obscure exactly the region being examined.

Off come earrings, necklaces, glasses, hairclips and metal hair ties, facial and tongue piercings, and any removable denture or retainer. Hearing aids usually come out too — say if you need them in to follow instructions, and it will be arranged around that. Fixed work such as crowns, bridges or an existing implant obviously stays where it is; it causes some local artefact, and the scan is planned in the knowledge that it is there.

Your phone and keys can stay in your pocket — they are nowhere near the beam.

Positioning takes longer than the exposure, and it is the part that decides whether the images are usable.

The device is adjusted to your height — most patients stand, and sitting is entirely normal too, particularly for anyone unsteady on their feet or using a wheelchair. Your chin goes on a support, you bite gently on a small positioning aid, and light supports rest against your temples or forehead to help you stay steady. Some devices project thin light lines across your face to align the region to be scanned; they are ordinary light, nothing more.

You remain upright throughout, in an open device. Nothing closes over your face, nothing touches your eyes, and you can see the room the whole time — which matters to anyone who has had an unhappy experience in an MRI tunnel.

Whether a lead apron is used depends on the device and the region being scanned; ask what applies to yours, and you will get a straight answer.

You will be asked to keep still, close your lips, breathe calmly through your nose and avoid swallowing during the rotation. Often you will also be asked to press your tongue gently against the roof of your mouth — it removes an air gap that would otherwise show up in the images.

Then the arm travels around your head, close but never touching, with a quiet mechanical hum. On most devices the exposure is over in a matter of seconds, and it feels like precisely nothing: no heat, no pressure, no sensation at all. X-rays cannot be felt.

The person operating the device steps behind a screen or just outside the door. That is not a comment on your safety — it is standard protection for someone who works beside the machine every day, whereas you are having a single examination. They can see and hear you throughout, and the scan can be stopped at any moment.

The computer reconstructs several hundred individual projections into a three-dimensional data set. That takes seconds to about a minute, depending on the volume and resolution.

The first thing checked is whether the data set is usable. If you moved during the rotation the reconstruction blurs, and occasionally that means a repeat — which is precisely why “keep still” is the one instruction worth taking seriously. It is uncommon, and nobody will be annoyed if it happens.

You are then shown your own jaw on the monitor. Most people find this the interesting part, and there is no reason to hurry it.

The data set is examined slice by slice in three planes, distances are measured on screen in millimetres, and the finding is explained in ordinary language: how much bone there is, where the nerve canal runs, how a root sits, what the dark area actually is. We also use AI support when reviewing scans — a second pair of eyes flagging regions worth a closer look, always alongside the dentist’s own assessment and never in place of it.

One legal detail that is worth knowing: the entire scanned volume must be assessed, not only the tooth you came about. A scan taken to plan an implant also contains part of the sinus and neighbouring structures, and anything noticeable elsewhere is documented and, where appropriate, referred on to the right specialty.

From there the conversation moves to what happens next — a treatment plan, a written cost plan for your fund where dentures or implants are involved, or sometimes the reassuring answer that nothing needs doing yet.

No recovery time, no restrictions, no aftercare. You can drive immediately, eat and drink whatever you like, go back to work and collect your children.

Nothing remains inside you either. X-rays pass through the body and stop the moment the machine stops — you are not radioactive afterwards, you cannot expose anyone else, and there is nothing to flush out. It is among the questions we are asked most often, and a perfectly sensible one to ask.

You can request your data set for your own records or for a second opinion; ask at reception so it can be prepared properly.

A strong gag reflex. The positioning aid sits between the front teeth, far from the throat, so this is far less of an issue than with impression trays — and we work with digital scanning rather than impression material anyway.

Tremor, pain or difficulty standing. Say so before positioning starts. Sitting is normal, the supports can be adjusted, and there is no prize for enduring an uncomfortable position.

Claustrophobia. The device is open on all sides and nothing covers your face. If you are anxious, ask to see it before deciding — most people find the reality much less alarming than the picture in their head.

Children. Scans in children are reserved for clear questions, with a smaller field and settings adjusted for a child rather than inherited from adults. Parents can normally stay in the room, standing to the side.

Anxiety in general. Say what you need. Being nervous about medical machinery is common, and it is treated here as information rather than as something to talk you out of.

Even in a practice where English is spoken every day, the short commands at the device often come out in German out of habit. This is what they mean:

If anything is unclear, say so — repeating an instruction costs a second, repeating a scan costs an exposure. English is one of the languages worked in here every day, together with German, Russian, Turkish, Ukrainian, Arabic, Kurdish and French, and asking for a sentence again at the device is entirely normal: English-Speaking Dentist in NRW.