Dental x-rays are one of the most useful diagnostic tools in dentistry. They let us see what we cannot see with the naked eye — decay between the teeth, bone loss around the roots, infections at the tip of the root, the position of unerupted teeth, and many other things. At Dentist Pymble, we use digital x-ray technology that delivers the diagnostic information we need at a fraction of the radiation dose of older film systems. This page covers why you need dental x-rays, the different types, whether they are safe, how often you need them, and what they cost.

Why do I need dental x-rays?

A visual examination alone only tells us about what we can see — the surfaces of the teeth, the visible gum, the soft tissues. A lot of the important stuff is hidden:

• Decay between the teeth — the most common location for cavities, completely invisible without an x-ray
• Bone loss around the roots — the hallmark of gum disease, can be significant before it is visible in the mouth
• Infections at the tip of the root — often painless, often only visible on x-ray
• The position of unerupted teeth — particularly wisdom teeth, but also supernumerary teeth and the developing adult teeth in children
• Cysts and other pathology — in the jaw bone, the sinuses, and the soft tissues

Without x-rays, we are working with one hand tied behind our back. The most common reason patients end up needing more complex treatment is that a small problem was missed at an earlier visit because x-rays were not taken. The most common reason patients avoid complex treatment is that small problems were caught early on routine x-rays.

Types of dental x-rays (bitewing, periapical, OPG, CBCT)

The main types of x-ray we use:

• Bitewing x-rays — show the crowns of the upper and lower teeth together, on a single film. The standard for detecting decay between the back teeth. Usually taken every 2-3 years for low-risk patients, more often for high-risk patients.
• Periapical x-rays — show the entire tooth from crown to root tip, on a single film. Used for diagnosing specific problems with a particular tooth (infection, root fracture, bone loss around a single tooth).
• OPG (orthopantomogram) — a panoramic x-ray that shows the entire mouth, all teeth, the jaw joints, and the surrounding structures in a single image. The standard for overall screening, particularly for wisdom teeth assessment, orthodontic planning, and implant planning.
• CBCT (cone beam computed tomography) — a 3D x-ray that provides highly detailed three-dimensional images. Used for complex cases (implant planning, impacted teeth, TMJ assessment, complex root canal anatomy). Higher radiation dose than a standard OPG, so used only when the 3D information is genuinely needed.

The right x-ray for you depends on what we are looking for. The dentist will explain what is being taken and why before any x-ray is done.

Are dental x-rays safe?

Yes. Modern digital dental x-rays use very low radiation doses, with a single bitewing x-ray delivering less radiation than a short flight. An OPG delivers a slightly higher dose (similar to a few days of background radiation), and a CBCT is higher still (similar to a few weeks of background radiation). For context, the natural background radiation we all receive every year is significantly higher than any of these.

The ALARA principle (As Low As Reasonably Achievable) guides our approach: we use the lowest dose that gives us the diagnostic information we need, and we only take x-rays when the benefit outweighs the small risk. For pregnant patients, we take additional precautions and may defer non-urgent x-rays, but the risk from a dental x-ray is still very small.

The digital x-ray systems we use at the Pymble practice reduce radiation exposure by up to 80% compared with traditional film x-rays, which is better for the patient and better for the environment.

How often do I need x-rays?

The frequency depends on your risk level and the type of x-ray:

• Bitewings — every 2-3 years for low-risk patients, every 1-2 years for moderate risk, every 6-12 months for high risk
• OPG — every 3-5 years for screening, or when a specific need arises (wisdom teeth, orthodontics, implant planning)
• Periapical — only when a specific tooth needs investigation
• CBCT — only when 3D information is needed for a specific clinical question

The dentist will tell you what is right for your situation. The honest answer is that the right frequency is “as often as needed to get the diagnostic information, and no more often than that.”

Cost of dental x-rays in Pymble

The cost depends on the type and number of x-rays taken. Bitewings are the least expensive (a few dollars each). Periapicals are similarly modest. An OPG is more, and a CBCT is the most expensive. Most x-rays are covered by private health fund preventative or major dental benefits, and our team can run a health-fund check on the day.

If you live in Pymble, Gordon, Turramurra, Wahroonga or anywhere else in the Ku-ring-gai area and you have questions about dental x-rays, ask at your next check-up. We see neighbouring Gordon patients and other nearby residents, and we will always explain why an x-ray is being recommended and what we are looking for.

Frequently asked questions

Do I need x-rays at every visit? No. X-rays are taken when indicated, which for most patients means bitewings every 2-3 years and an OPG every 3-5 years. The dentist will tell you what is right for your situation.

Are dental x-rays safe during pregnancy? The radiation dose from dental x-rays is very small, but we take additional precautions during pregnancy. Non-urgent x-rays are usually deferred until after the birth, but urgent x-rays (to diagnose a painful or infected tooth) are still done with appropriate shielding.

Can I refuse x-rays? Yes, you can refuse any treatment, including x-rays. The dentist will explain the implications of not having the x-ray (what we might miss, what we cannot diagnose without it) and document the refusal. Most patients who understand the rationale agree to the recommended x-rays.

What is the difference between an OPG and a CBCT? An OPG is a 2D panoramic x-ray that shows the entire mouth and surrounding structures in a single flat image. A CBCT is a 3D x-ray that provides much more detailed three-dimensional information. CBCT is used for specific complex cases; OPG is the standard screening tool.

How long do x-rays take? Bitewings and periapicals take a few minutes each. An OPG takes about 30 seconds of actual scanning time. A CBCT takes about 10-20 seconds of scanning time, plus setup.