Dental X-rays are images that let a dentist see what a visual exam cannot: the areas between teeth, below the gumline, inside tooth roots, and the condition of the supporting bone. Dentists request them to spot cavities, check developing problems, and plan treatment. The most common types are bitewing, periapical, and panoramic images, each serving a different purpose.
Many patients hear "we need to take some X-rays" and wonder why, especially when nothing hurts. The answer is that a visual examination has hard limits. A dentist looking into your mouth can see the outer surfaces of your teeth and gums, but cannot see between teeth where they touch, under existing fillings, inside the roots, or into the bone that holds your teeth in place. X-ray images fill those gaps. They are a diagnostic aid — a way of gathering information so that problems can be found earlier and treatment plans can be based on a fuller picture.
Why Dentists Request X-Rays
The single biggest reason is early detection. Some dental problems develop silently for a long time before causing symptoms. A cavity forming between two teeth, bone changes around a tooth root, or an issue developing under an old filling may cause no pain at all in the early stages. Images can reveal these problems while they are small, when the options for addressing them are typically simpler.
X-rays are also used for planning. If a dentist is considering a filling, a crown, a root canal, an extraction, or orthodontic work, images help them understand the shape of the roots, the amount of supporting bone, and the position of nearby structures before any work begins. They are also used to establish a baseline: images taken when you are healthy give the dentist something to compare against at future visits, so gradual changes become visible.
If you are new to a practice, X-rays are more likely to be requested at your first visit, simply because the office has no prior images of your mouth. You can read about the rest of that first appointment in our guide to a first dental visit.
Bitewing X-Rays: The Routine Close-Up
Bitewing images are the type most adults encounter most often. The name comes from how they are taken: you bite down on a small tab or holder that keeps the sensor or film in position while the image is captured.
#### What They Show
A bitewing image typically shows the crowns of several upper and lower teeth in one area of the mouth — usually the back teeth — with the upper and lower teeth visible in a single frame. Because the image captures the teeth where they touch each other, it is especially useful for spotting cavities forming between teeth, which are among the hardest cavities to detect visually.
#### When They Are Used
Dentists commonly request bitewings at routine checkups when they want to check for new decay between teeth or monitor areas they are watching over time. A standard set covers both sides of the mouth. Since these are the images most associated with the regular dental checkup, many patients have several sets on file from different years, which makes year-to-year comparison possible.
#### What the Process Feels Like
The sensor or film holder is placed inside your mouth next to the teeth being imaged, and you bite gently to hold it in place. The positioning can feel awkward, and some people gag slightly when something sits toward the back of the mouth — this is common, and dental staff deal with it routinely. Each image takes only a few seconds of stillness, and the whole set is usually finished in a few minutes.
Periapical X-Rays: The Whole Tooth, Root Included
A periapical image shows an entire tooth from the crown down through the root tip, along with a portion of the surrounding bone. "Periapical" refers to the area around the tip of the root.
#### What They Show
Where a bitewing shows the crowns of several teeth, a periapical image goes deep on one or two teeth. It reveals the full length of the root, the bone around the root tip, and any changes in the tissues at the end of the root. This makes it the image of choice when a dentist is investigating a specific tooth — for example, one that is sensitive, has a deep cavity, has had trauma, or is being evaluated for root canal treatment or an extraction.
#### When They Are Used
Dentists request periapical images when something specific needs a closer look below the gumline: a tooth that hurts, a tooth with a large or deep filling being monitored, or a tooth being planned for a filling or other restorative work. They are problem-focused rather than routine-screening images, though they are sometimes taken as part of a comprehensive first-visit set.
Panoramic X-Rays: The Full-Mouth Overview
A panoramic image captures the entire mouth in a single wide picture: all the teeth in both jaws, the jaw joints, the sinuses above the upper teeth, and a good portion of the jawbone.
#### How It Is Taken
Unlike the other types, a panoramic image is taken with the machine rotating around your head while you stand or sit still, usually biting on a small guide to keep your teeth in position. Nothing goes inside your mouth, which many patients prefer. The process takes under a minute, and the result is one broad image rather than a set of small ones.
#### What It Is Used For
Because it shows everything at once, a panoramic image is useful for the big picture: the overall development and alignment of teeth, the position of unerupted teeth such as wisdom teeth, the condition of the jaw joints, and an overview of bone levels. Dentists and orthodontists use it when planning extensive work, evaluating wisdom teeth, or assessing development in younger patients. The trade-off is detail: a panoramic image shows less fine detail of individual teeth than bitewing or periapical images, so it complements rather than replaces them.
How Often X-Rays Are Taken
There is no fixed schedule that applies to everyone. Frequency depends on your age, your oral health history, your risk of decay or gum problems, and whether you have symptoms. A patient with a history of frequent cavities may have bitewings taken more often than someone with a consistently healthy mouth and no risk factors. New patients often get a fuller set at the first visit to establish a baseline, and follow-up images are then taken only when the dentist judges them useful.
This is one of the most common questions patients ask, and it is worth raising directly: if X-rays are suggested, ask why they are being recommended now and what the dentist hopes to learn from them. A straightforward explanation is part of good care, and most dentists are happy to give one.
What Happens During the Imaging Process
Regardless of type, the practical experience is similar. You will be asked to remove anything that could interfere with the image — glasses, earrings, necklaces, and removable dental appliances such as dentures or retainers. The staff member positions the sensor or the machine, asks you to hold still for a few seconds, and takes the image. With digital systems, which most offices now use, the image appears on a screen almost immediately, and the dentist can review it with you during the same visit.
If you are pregnant or think you might be, tell the dental office before any images are taken. This is standard practice, and the office will discuss with you how to proceed. Similarly, if you have questions about why a particular image is needed, or about the imaging process in general, raise them before the images are taken rather than afterward. The principle is simple: any question you have about your own care is worth asking, and the answers should make sense to you.
How Dentists Use the Images With You
One of the genuinely useful parts of a modern dental visit is that the dentist can show you the images on a screen and point to what they are seeing. If a cavity is visible between two teeth, they can show you exactly where. If they are monitoring an area, they can pull up last year's image alongside this year's and compare. Do not hesitate to ask them to walk you through what you are looking at — most patients find the images hard to interpret at first, and a two-minute explanation makes the findings concrete rather than abstract.
This shared review is also where treatment discussions start. If the images reveal something that needs attention, the dentist will explain what was found, how significant it appears to be, and what the options are. As with any treatment recommendation, you can ask for time to consider, ask about alternatives, and discuss the plan with a qualified dental professional before deciding.
FAQs
Are dental X-rays really necessary if nothing hurts?
They can be, because some dental problems cause no pain until they are advanced. Cavities between teeth and changes in the bone around tooth roots often develop silently, and images are the main way to detect them early. That said, necessity is always individual: it depends on your history, risk factors, and symptoms. If X-rays are recommended and you are unsure why, ask the dentist to explain what they are looking for in your specific case. A clear, specific reason is a reasonable thing to expect.
How do bitewing and panoramic X-rays differ?
They serve different purposes. Bitewing images are close-ups showing the crowns of a few teeth at a time, with good detail — ideal for spotting cavities between teeth. A panoramic image is a single wide view of the entire mouth, jaws, and surrounding structures, with less fine detail per tooth — ideal for the overall picture, wisdom tooth position, and treatment planning. Dentists use them for different questions, and one does not replace the other.
What should I do if I gag during X-rays?
Tell the staff member — it is extremely common, and they have techniques to help, such as adjusting the sensor position, working quickly, or suggesting breathing through your nose. Panoramic images, which involve no sensor inside the mouth, are sometimes easier for people with a strong gag reflex. There is no need to feel embarrassed; dental teams encounter this daily and will work with you to get usable images as comfortably as possible.
Can I ask to see my X-rays?
Yes, and you should feel free to. Most offices use digital imaging, so the dentist can pull the images up on a screen and walk you through them during your visit. Asking to see them helps you understand the findings and any recommended treatment. You can also ask for copies of your images to be sent to another dentist or specialist if you are referred or switch practices — they are part of your dental records.
I am pregnant — what should I tell the dental office?
Tell the office before any X-rays are taken, ideally when booking or at check-in. This is standard information dental teams need, and they will discuss with you how to proceed based on your situation. Routine dental care during pregnancy is a topic worth discussing with both your dentist and your prenatal care provider, so that decisions about timing and imaging are made with full information on all sides.
This site is educational information only — not medical advice. Consult a qualified dental professional about your own situation.
