Treatment Process

Why is a CBCT scan taken before dental implants?

How a 3D scan shows what a panoramic X-ray cannot

Why an ordinary X-ray is not enough when planning implants, and what a 3D CBCT scan actually shows, is often not explained in full. Below we set out what a panoramic X-ray cannot show, the CBCT scan's radiation dose with real comparisons, what happens if you are pregnant, and what happens if you already have an old scan. In Implant72's protocol, this scan is taken on the first of the three clinical days, before surgery; the plan is finalised that same day, based on that image.

Short answer

A panoramic X-ray shows only a flat projection of the jaw; it gives an idea of the height of the bone, but not its width, the depth of the nerve canal or the position of the sinus floor. A CBCT scan shows the same area in millimetre-thin slices; where the implant goes, at what angle and what length, is decided by looking at this image. The radiation dose is low, and in dentistry it is requested only when needed. In Implant72's protocol, this scan is taken on the first of the three clinical days, before surgery.

When it is taken: Day 1 of the protocol, before surgery
How it differs from a panoramic: It also shows width and depth
Radiation: Low dose, only when needed
If you have an old scan: Bring it; we will check whether it is current

How the CBCT scan shows what a panoramic X-ray cannot

A panoramic X-ray is a single-plane image of your jaw, flattened from front to back. It gives an idea of how far up the bone extends, but because it is two-dimensional it carries no information about thickness; structures in front of and behind each other overlap in the same image. The decision on an implant is made not just on height but together with width and neighbouring structures; a panoramic X-ray cannot show either of these.

A 3D CBCT scan uses a device that rotates around your jaw to take hundreds of slice images, and combines them on computer into a single 3D model. The result is an image you can cut through and look at, on any plane you choose, at millimetre scale. At every point where an implant is planned, the width of the bone, the depth of the nerve canal, the position of the sinus floor and the thickness of the hard outer layer, the cortical bone, are all measured separately.

Each of these measurements turns into a decision. Width decides what diameter of implant will fit safely. The depth of the nerve canal sets the limit on how long the implant can be and at what angle it is placed. The position of the sinus floor shows whether extra surgery is needed at the back of the upper jaw. The thickness of the cortical bone shows whether the surface the strategic implant will anchor into is sound.

To be honest about radiation: a dental CBCT scan is a low-dose imaging method, and in dentistry it is requested only when clinically needed. Cleveland Clinic's patient information compares the dose from a full set of dental X-rays with familiar everyday sources: building materials such as granite or ceramic tiles, flying at high altitude, and the natural background radiation that comes from the sun and the ground. The dose from a 3D CBCT scan varies with the area scanned and is generally a little higher than that set, though it still falls within a range considered low dose in dentistry. This does not mean the dose is negligible; it means it is not an unusual one either.

The honest answer to whether a CBCT scan can be taken during pregnancy is this: dental imaging is generally considered safe in pregnancy and while breastfeeding, but most dentists avoid requesting imaging in pregnancy unless it is genuinely needed. If you are pregnant, or think you might be, tell us before your appointment; treatment is timed accordingly.

If you have a panoramic X-ray or CBCT scan taken recently, bring it; it is useful for a first assessment and can save an unnecessary repeat. But for a treatment decision, the image needs to be current: a tooth extraction, long-term denture wear or simply the passage of time can have changed the shape of the bone. If the image is clearly out of date, asking for a new scan is about protecting the decision itself, not about you.

In Implant72's protocol, this scan is taken on the first of the three clinical days, before surgery. On that day, the plan is reassessed against the CBCT scan; how many implants, at what angle and depth, is settled, and surgery follows on the same day. There is no months-long wait between imaging and surgery; the two complete each other within the same day.

Not every missing tooth needs a scan of the same scope. If a single implant is planned, a smaller-volume scan covering a narrow area can be enough; with a full-mouth plan, a wider area is scanned because several regions are assessed at once. Guidance in dentistry is that imaging should only be requested when it will genuinely provide information that changes treatment; so the decision is not a single fixed rule, it is made according to the scope of your own case.

The structure that matters most also changes between the upper and lower jaw. In the lower jaw, the structure of real importance is the nerve canal that carries sensation to the lip and chin, while at the back of the upper jaw it is the floor of the sinus cavity. After tooth loss, as bone height in this area decreases, the sinus cavity can expand downward; the CBCT scan shows this distance to the millimetre as well. Which jaw is being treated decides which structure is watched most closely on the scan, and shapes the plan accordingly.

When a panoramic X-ray is enough, and when a CBCT scan is essential

The distinction below shows which imaging is enough in which situation. The firm decision only becomes clear after an examination.

The tooth can be saved

An implant is plannedThe decision on an implant rests on a 3D measurement of the bone; here a CBCT scan is a standard step, not an optional one.
There is a suspicion of not enough boneLow bone height seen on a panoramic X-ray only tells part of the story; only a CBCT scan shows the true width and the state of the cortical layer.
Work will be close to the nerve or the sinusA safe plan cannot be made without knowing the distance to these structures to the millimetre.
The area has had surgery beforeIn a jaw with an old fracture, a cyst or a surgical scar, a 3D image prevents surprises.

Saving it is unlikely to hold

Only a general check-up or decay screening is neededA panoramic or a standard intra-oral X-ray is enough for this purpose; a CBCT scan is not needed at every check-up.
It is a non-urgent assessment during pregnancyIf treatment can wait, imaging can be left until after the birth too.
You already have a sufficiently current CBCT scanScanning the same area again would be unnecessary exposure; the existing image is assessed first.
For routine check-ups in child patientsBecause sensitivity to radiation is higher, the decision to image a child is made only when it is genuinely necessary.

How the day of the scan works

In Implant72's protocol, these steps take place on the first of the three clinical days, before surgery.

1
Registration and a short medical history
We ask about your general health, the medicines you take, and whether you might be pregnant; these affect the imaging decision.
2
The scan takes a few seconds
The device rotates around your head while you stay still. It is a painless procedure that needs no needles or contact.
3
The image is processed the same day
The 3D model is ready within a few minutes; the dentist can cut through the bone on any plane and examine it.
4
The plan is reassessed against the image
How many implants, at what angle and depth, and whether a graft is needed, are settled by looking at this image; the plan discussed beforehand can change at this point.
5
Surgery follows the same day
There is no separate appointment or waiting between imaging and surgery; both are part of the same day.

Panoramic X-rays, CBCT scans and other imaging methods

Knowing what each one is used for makes it easier to understand why your dentist asks for a particular image.

Panoramic X-ray

Shows the whole jaw in a single flat image; it is enough for general screening, decay and tooth position, but not enough on its own for implant planning.

Intra-oral (periapical) X-ray

Shows a single tooth and the bone around it in close-up; used for root canal treatment and assessing a limited area.

3D CBCT scan

Shows the bone as a volume; this is the preferred method for implants, impacted tooth surgery and complex cases.

Medical CT scan

A broader-purpose scan taken in hospitals; it is requested for other medical reasons, not for dental planning, and is not routine in dental practice.

What you need to know about imaging

We are setting these out plainly, without overstating them.

There is radiation, but at a low dose

Like every imaging method, a CBCT scan involves some radiation. It is a low dose, comparable to some everyday sources; it is not zero, but it should not be requested without a reason either.

Not every image is taken for the same purpose

A panoramic X-ray is enough for a check-up, while an implant plan needs a CBCT scan; more imaging than necessary is not to your benefit.

An old image cannot carry a current decision

The state of your bone today may not match an image taken months or years ago; tooth extraction and denture wear change the bone.

Metal restorations can cause interference on the image

If you have dense metal fillings or old crowns in your mouth, some blurring can appear on the image; this rarely affects planning, but it is worth telling your dentist.

Movement can spoil the image

Moving your head during the scan causes blurring on the image and can sometimes mean the scan has to be repeated. Because it takes only a few seconds, this risk is low, but it is worth watching for, especially with children and restless patients.

What happens after the CBCT scan

The scan itself is painless and needs no healing; the sequence below describes how the process continues after the image is taken.

The same day, within a few minutes
The image is processed and the dentist examines the bone in 3D; the first assessment is made the same day.
The same day, the plan is settled
How many implants, and at what angle and depth they will be placed, and whether a graft is needed, take their final form based on this image.
The same day, surgery follows
In Implant72's protocol there is no wait between imaging and surgery; both take place one after the other on the first of the three clinical days.
Later check-ups
As treatment moves forward, further imaging is requested according to the clinic's follow-up plan if it is needed; it is not a routine repeat.

Message us right away if

You think you could be pregnant before imaging. Tell us before your appointment; the timing changes if needed.
You are not sure your old image is still current. Send us the image and let us decide whether it is still current.
You have dense metal restorations in your mouth. Telling us this beforehand helps us plan for the quality of the image.

What decides the cost on the imaging side

We do not give figures on this page; the price is only given, item by item and in writing, after your examination and CBCT scan. But it helps to know which items affect the budget on the imaging side:

The scope of the scan: Whether a single area or the whole jaw is scanned, and at what resolution, affects the cost.
Whether further imaging is needed: If there is metal interference or an unclear finding, a further scan may be requested; we explain in writing when and why we ask for this.
Planning software and the dentist's assessment: Turning the raw image into a surgical plan is separate work; it is distinct from the scan itself, but part of the plan.
Whether an image brought from elsewhere is suitable: If the image you bring is good enough, the cost of a repeat scan disappears; if it is not, we tell you so from the start.

Frequently asked questions

Why is a CBCT scan taken before dental implants?

Because the decision on where the implant goes, at what angle and what length, is made by looking at the width of the bone, the depth of the nerve canal and the position of the sinus floor. A panoramic X-ray shows none of these three; it only gives a rough idea of the height of the bone.

Is a dental CBCT scan harmful because of radiation?

It is a low-dose imaging method, and it is requested only when clinically needed. Its dose varies with the size of the area scanned; even though it is a little higher than a general set of dental X-rays, it still falls within a range considered low dose in dentistry. It is not zero, but it is not a dose to be requested without reason either.

I have a panoramic X-ray, do I have to get a CBCT scan too?

A panoramic X-ray is useful for a first assessment, but it is not enough for an implant decision. Because it does not show the width of the bone, the depth of the nerve canal or the state of the cortical layer, a treatment plan is not drawn up without a CBCT scan.

I am pregnant, can I have a CBCT scan?

Dental imaging is generally considered safe, but most dentists avoid imaging during pregnancy unless it is genuinely needed. If you are pregnant, or think you might be, be sure to tell us before your appointment; timing is planned accordingly.

I have a CBCT scan from another clinic, will I need a new one?

Send us the image and let us assess it first. If it is current and thorough enough, a repeat scan may not be needed; if something has changed the bone since, such as a tooth extraction or long-term denture wear, we will ask for a new scan.

Is a CBCT scan painful?

No. The device rotates around your head while you stay still; no needles or contact are involved. The scan takes a few seconds.

Does surgery happen on the same day as the scan?

In Implant72's protocol, yes. The scan is taken on the first of the three clinical days, the plan is settled against it that same day, and surgery follows; there is no separate appointment or wait.

How long does the scan take, and is any special preparation needed?

The scan itself takes a few seconds; the whole appointment, with preparation, is completed in around fifteen minutes. If you are wearing metal jewellery, glasses or a removable denture, you will be asked to take them off before the scan; apart from that, no special preparation is needed.

Is there a difference between a CBCT scan and an MRI, and which is used for implant planning?

The two show different things. A CBCT scan shows bone clearly, and because implant planning rests on bone, this is the preferred method. An MRI shows soft tissue better, and it is not a routine part of implant planning in dentistry; it is requested when there is a separate medical reason for it.

Sources

Send your X-ray and we will tell you which option is realistic for your tooth.

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Next step

Send your X-ray and we will talk through the options.

Share your CBCT or panoramic X-ray. We will write back within 24 hours on which option is realistic for your tooth.

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