Digital dental X-rays work by passing a brief, controlled X-ray beam through the teeth onto a small electronic sensor or phosphor plate, which turns the pattern into an image on a computer within seconds. A dentist recommends images when the information could change your care, not automatically at every visit.
Key Takeaways
- A digital dental X-ray captures how much of an X-ray beam passes through teeth and bone, using a sensor or plate instead of film, and converts it into a viewable digital image.
- Images are prescribed after clinical judgment about what question needs answering, and the view is chosen to fit that question.
- Dentists use radiographs to see structures that a visual exam alone may miss, such as areas between teeth or around roots.
- Digital images appear almost immediately and can be enlarged and compared over time, but they do not remove the need to justify each exposure.
- Patients usually feel brief positioning pressure and a short exposure; comfort varies with anatomy and the type of view.
What is a digital dental X-ray?
A digital dental X-ray (also called a digital radiograph) is an image of the teeth, roots and supporting bone that is recorded by an electronic receptor and displayed on a computer. It uses the same basic physics as traditional dental film: X-rays pass through the mouth, and denser structures block more of them. What changes is how the image is captured, processed and stored.
Digital dental X-rays are a diagnostic tool, not a treatment. The image helps a dentist decide whether a problem is present, how large it is and what to do about it. On its own it does not prevent decay or gum disease, and it does not replace the clinical exam.
How a digital sensor captures an image
Dental radiography begins with a controlled X-ray beam directed toward a small region of the mouth. Tissues absorb the beam differently: denser structures such as enamel and metal restorations typically appear lighter on the resulting image, while less dense areas, such as decay or the pulp inside a tooth, appear darker. That contrast is what allows a clinician to examine teeth, restorations and bone patterns.
In digital systems, the receptor is either a solid-state sensor placed in the mouth or a phosphor plate that is scanned after exposure. Instead of chemical film development, the receptor's signal is processed into a digital file. The American Dental Association notes that digital receptors are among the options used in modern dental radiography and that once imaging is justified, exposure should be kept as low as reasonably achievable for the diagnostic task.
| Receptor | How it works | What patients notice |
|---|---|---|
| Solid-state sensor (wired or wireless) | Converts X-rays into an electronic signal that goes straight to the computer | Image appears in seconds; the sensor is rigid and can feel bulky at the back of the mouth |
| Phosphor storage plate | A thin, flexible plate stores the X-ray pattern, then a scanner reads it | Thinner and more flexible, similar in feel to film; a short scanning step before the image appears |
| Traditional film (for comparison) | Film is exposed, then developed with chemicals | Wait for processing; images stored physically |
Digital capture does not remove the need for justification. The Canadian Dental Association's position on control of X-radiation in dentistry states that radiographs should be based on clinical examination and a need for information that could contribute to diagnosis or treatment planning. Suitable recent images should be considered before new exposures are made.
This explanation is conceptual. Exact sensors, software interfaces and workflow details vary by practice and should be confirmed with the dental team if you have specific questions about what will be used at your visit.
Types of digital dental X-rays and what each shows
Different views answer different questions. The team selects the view for the clinical question rather than taking every possible image by default.
| View | Where the receptor is | What it shows | Common reasons |
|---|---|---|---|
| Bitewing | Inside the mouth, you bite on a tab | Crowns of upper and lower back teeth together, plus the bone level between them | Decay between teeth, fit of fillings, early bone loss |
| Periapical | Inside the mouth, beside one area | A whole tooth from crown to root tip, with surrounding bone | Toothache, infection at the root, trauma, before a root canal or extraction |
| Occlusal | Inside the mouth, held between the teeth | The floor or roof of the mouth | Selected developmental questions, some injuries or abnormalities |
| Panoramic | Outside the mouth; the machine rotates around the head | All teeth, both jaws and nearby structures in one wide image | Wisdom teeth, broad overview, some planning |
| Cephalometric | Outside the mouth, side view of the head | Relationship between teeth, jaws and skull | Orthodontic assessment |
| CBCT (3D) | Outside the mouth | Three-dimensional view of teeth, bone and nearby anatomy | Selected implant, root and wisdom tooth questions |
Intraoral views (bitewing and periapical) are the ones most people have at routine checkups. Extraoral views show broader relationships. A 3D CBCT scan is a separate technology used for selected planning questions and is not a substitute for bitewings or periapicals; our guide to CBCT vs. dental X-rays explains the difference.
What happens during the appointment
Imaging usually follows a review of concerns and a clinical look at the area in question. The dental professional explains which images are proposed and why. You can ask what the image is expected to show and whether existing radiographs from another office could be transferred instead of repeating exposures.
For intraoral images, a dental hygienist or dental assistant positions a sensor or plate beside the teeth. A holder often stabilizes the receptor and helps align the beam. You may be asked to bite gently on a positioning device. For some extraoral images, you stand or sit while the machine moves around your head; stay still as instructed.
Protective measures follow professional judgment and current guidance, and that guidance is changing. Health Canada's Safety Code 30 says patients must be provided with a thyroid shield when it will not interfere with the diagnostic information, especially for children. In 2024, the American Dental Association stopped recommending thyroid collars and lead aprons for dental imaging, because they can block the beam and cause retakes. Ask the team what protective measures they use for your specific images.
The exposure itself is brief. The team then checks whether the image is diagnostically acceptable. A retake may be needed if the receptor moved, the angle was incorrect or the image does not answer the clinical question. Retakes should be limited to what is necessary.
If you are pregnant, think you might be pregnant, or have had recent dental or medical imaging elsewhere, tell the team before radiographs are taken. That information supports justification and coordination of care.
How dentists use the image
A radiograph is a diagnostic aid, not a standalone verdict. The dentist interprets the image together with your symptoms, clinical findings and history. Magnification, contrast adjustment and side-by-side comparison with earlier images, when available, can help the clinician evaluate changes over time.
Common reasons to review a digital dental X-ray include checking for decay between teeth, assessing bone levels around teeth, evaluating the area around a root tip, examining the fit of existing restorations, or planning treatment where underground structure matters. The image may rule a problem in, rule one out or show that monitoring is reasonable. Our article on why dentists take X-rays goes through those reasons in more detail.
Radiographs have limits. Early enamel changes, some cracks and certain soft-tissue conditions may not be fully visible on a standard dental X-ray. Additional tests, clinical probing, different image types or referral may still be needed. A clear radiograph does not guarantee that every possible condition is absent.
When findings are explained, ask the dentist to point to the area of interest on the screen and describe how certain the interpretation is. Understanding the "why" behind a recommendation is part of informed discussion about next steps. An intraoral camera photo can sometimes help too, because it shows the surface of the tooth in colour while the X-ray shows what is underneath.
For service-level information about imaging at the practice, see digital dental X-rays.
Digital vs. film X-rays: what changes and what does not
Digital dental X-rays change the workflow more than the purpose.
| Digital X-rays | Film X-rays | |
|---|---|---|
| Image available | Within seconds on a screen | After chemical processing |
| Adjusting the image | Can be enlarged and contrast adjusted | Fixed once developed |
| Sharing | Can be sent securely to a specialist or new dentist | Copies must be duplicated and mailed |
| Chemicals | No developing chemicals | Requires processing chemicals and disposal |
| Radiation | Uses ionizing radiation; receptors can support lower exposure when technique is optimized | Uses ionizing radiation |
| Need for justification | Still required | Still required |
What digital does not do is make an image automatically necessary or risk-free. The ADA also notes a concern called "exposure creep", where settings can drift upward over time to produce a cleaner-looking image. Good practice means matching exposure settings to the diagnostic task. For more on radiation and safety, read our guide to whether digital dental X-rays are safe.
Storage, records and follow-up comparison
Digital images become part of the dental record. Secure storage supports continuity of care, insurance documentation when applicable and comparison at future visits. Practices follow privacy and record-keeping obligations applicable in their jurisdiction; ask the front desk how records are shared if you change providers.
Comparison with earlier radiographs is one reason to avoid unnecessary duplicate exposures. If you recently had images taken elsewhere, request a transfer so the dentist can determine whether new images are still needed. The FDA and ADA emphasize reviewing imaging history as part of justifying examinations.
Follow-up imaging intervals are individualized. There is no universal calendar that requires bitewings every set number of months for every patient. Risk of decay, periodontal status, symptoms, age and previous findings all influence timing. The ADA states that radiographic timing depends on current oral health needs rather than a one-size-fits-all schedule.
If a new problem appears between visits (pain, swelling, trauma), the dentist may recommend targeted images sooner than a routine recall interval. Conversely, a low-risk patient with recent adequate images may not need repeats at the next checkup.
What patients typically feel
Most people describe digital dental X-rays as quick. The main sensations are pressure from the sensor or plate and the need to hold still. Sensors can feel bulky, especially in smaller mouths or near the back teeth. Tell the team if you have a strong gag reflex; positioning adjustments, breathing through the nose and brief pauses often help.
There is no lingering "radiation feeling" after a dental exposure. Anxiety is common and worth mentioning in advance so the team can explain each step.
Special situations
- Children: smaller sensors and extra time help. Children are more sensitive to radiation over a lifetime, so images are selected carefully for their age, decay risk and development.
- Pregnancy: tell the team first. The CDA advises that elective radiographs may be deferred, while essential or emergency care should use the minimum number of images needed.
- Limited mouth opening or TMJ pain: say so before positioning; the team may use different holders or an extraoral view.
- Strong gag reflex: front teeth are often imaged first, and a short break between images is fine.
- Dental anxiety: ask the team to explain each step before it happens. You can raise a hand to pause.
Discomfort is not the same as harm from the imaging decision. Conversations about necessity, alternatives and protective measures belong before the exposure whenever practical. Afterward, ask whether the images were adequate and whether any findings require treatment, monitoring or another type of image.
Digital X-rays at our Truro office
Landmark Dental Care uses digital X-rays as part of exams and emergency visits at our office at 125 Queen St in downtown Truro, where we see families from Truro, Bible Hill and across Colchester County. Images appear on the screen during the visit, so your dentist can show you what they see and explain it in plain terms.
If you are moving to the area or switching dentists, ask your previous office to send recent X-rays before your first visit. That gives your dentist a starting point and may reduce the number of new images needed. The practice also offers 3D CBCT imaging for selected planning questions, and an intraoral camera for close-up photos of the teeth.
Coverage for X-rays depends on your plan. If you have questions about the federal program, see our Canadian Dental Care Plan page and call to confirm current participation and billing.
FAQ
Are digital dental X-rays the same as medical CT scans?
No. Routine digital dental X-rays are small-field dental radiographs for teeth and supporting structures. Medical CT and dental CBCT are different technologies used for different clinical questions and are not interchangeable with bitewing or periapical images.
Do digital X-rays hurt?
Most patients feel brief pressure from positioning rather than pain from the exposure itself. Tell the dental team if sensor placement is difficult so they can adjust technique or timing.
Why might an image need to be retaken?
Movement, incorrect angulation or an image that does not show the area of concern can require a retake. Retakes should be limited to what is needed for a diagnostically useful result.
How long does a digital dental X-ray take?
Each exposure lasts a fraction of the time it takes to position the sensor, and the image appears within seconds. A set of bitewings usually takes a few minutes, mostly for positioning.
Can I get a copy of my digital X-rays?
Usually, yes. Digital images can be shared securely with another dentist or a specialist; ask the front desk how to request a transfer and whether a signed consent is needed.
Next step
To learn about digital dental imaging at Landmark Dental Care, call 902-893-2919, ask about radiographs during your examination at 125 Queen St in Truro, or book through our contact page. Imaging recommendations should always be tied to your individual clinical needs.
References
- Canadian Dental Association: Control of X-Radiation in Dentistry
- American Dental Association: X-Rays/Radiographs
- Health Canada: Radiation Protection in Dentistry — Safety Code 30 (2022)
- American Dental Association: ADA releases updated recommendations to enhance radiography safety in dentistry
- U.S. FDA: Dental Cone-beam Computed Tomography
- ADA/FDA: Dental Radiographic Examinations — recommendations for patient selection (PDF)
This article provides general educational information and is not a diagnosis or a substitute for care from a dentist or other qualified health professional.
About this guide
This article was written and reviewed by the Landmark Dental Care Team at Landmark Dental Care, 125 Queen St, Truro, NS B2N 2B4. It is general patient education and is not a diagnosis or a substitute for an examination. If you have pain, swelling or a change in your mouth, call us at 902-893-2919 so a dentist can assess you.