What This Guide Covers and Who It Is For
This guide explains the four main types of dental X-rays so you know what to expect at your next appointment. It is written for any patient who has been told they need X-rays and wants to understand why.
Dental X-rays, also called radiographs, use a small amount of radiation to create images of structures inside your mouth. These images show things your dentist cannot see during a visual exam, such as cavities forming between teeth, infections at a tooth root, or bone loss in the jaw. According to the American Dental Association, radiographs are a routine part of preventive dental care [3].
You may receive X-rays from a general dentist, but certain types are more commonly ordered by specialists. Oral and maxillofacial radiologists are dentists who complete additional training in diagnostic imaging. They interpret complex scans and help other specialists plan treatments like implant placement or jaw surgery [2].
Below, you will find details on each X-ray type, radiation levels, cost ranges, preparation steps, and guidance on when a specialist referral makes sense.
The Four Main Types of Dental X-Rays
Each type of dental X-ray captures a different view, and your dentist chooses the type based on what information is needed.
Bitewing X-Rays
Bitewing X-rays show the upper and lower back teeth in a single image, making them ideal for finding cavities between teeth. The name comes from a small tab you bite down on to hold the sensor in place.
Dentists typically take two to four bitewing images during a routine checkup. These images reveal early decay between molars and premolars, areas that are difficult to examine visually. Bitewings also show the height of the bone between teeth, which helps detect early signs of periodontal disease (gum disease that damages the bone supporting your teeth) [3].
Because they focus on a specific area, bitewing X-rays use a very small amount of radiation. A set of four bitewing images delivers roughly 0.005 millisieverts (mSv), a unit used to measure radiation dose. For comparison, the average person receives about 3 mSv per year from natural background sources like the sun and soil [3].
Most adults receive bitewing X-rays every one to two years, depending on their cavity risk. Patients with a history of frequent cavities or active gum disease may need them more often.
Periapical X-Rays
Periapical X-rays capture the entire length of a single tooth, from the crown (the visible part) down to the root tip and the surrounding bone. This makes them essential for diagnosing problems below the gumline.
Your dentist may order a periapical X-ray when you have a toothache, swelling, or sensitivity to hot and cold. The image can reveal an abscess (a pocket of infection at the root tip), a fracture in the root, or a cyst in the jawbone. Endodontists, the specialists who perform root canal therapy, rely heavily on periapical X-rays to assess the shape and condition of root canals before and after treatment [3].
A full-mouth series consists of about 14 to 20 periapical images combined with bitewings. This series maps every tooth and is often taken for new patients or when a dentist suspects widespread problems. The total radiation dose from a full-mouth series is considered very low, with typical doses ranging from approximately 0.02 to 0.17 mSv, depending on the technology (digital vs. film) and technique (rectangular vs. round collimation) used by your dentist. Offices that use digital sensors with rectangular collimation can reduce the dose to as low as 0.017 mSv, while older setups using round collimation may deliver closer to 0.15 to 0.17 mSv [3] [5]. If you are curious about how your dentist keeps doses low, ask whether they use digital sensors and rectangular collimation, two features that significantly reduce radiation exposure.
Like bitewings, periapical X-rays use a small sensor or film placed inside your mouth. You may feel mild pressure, but the process is quick, usually a few seconds per image.
Panoramic X-Rays
A panoramic X-ray, sometimes called a "pano," captures the entire mouth in one wide image. Nothing is placed inside your mouth. Instead, the X-ray machine rotates around your head while you stand still.
The resulting image shows all of your teeth, both the upper jaw (maxilla) and lower jaw (mandible), the sinuses above your upper teeth, and the TMJ (the joint that connects your jaw to your skull). Panoramic X-rays are commonly used to evaluate wisdom teeth, plan orthodontic treatment, assess jaw fractures, and screen for tumors or cysts [3].
Because the image covers a large area, a panoramic X-ray does not show fine detail as clearly as a bitewing or periapical. Your dentist may use it as a screening tool and then order more focused images if a problem area is found. The radiation dose from a single panoramic X-ray is approximately 0.01 to 0.03 mSv [3].
Panoramic X-rays are often taken every three to five years, or as needed based on clinical findings. They are especially useful for children and patients who have difficulty tolerating sensors placed inside the mouth.
Cone-Beam Computed Tomography (CBCT)
CBCT produces a three-dimensional image of your teeth, bone, nerves, and soft tissues. It gives specialists information that two-dimensional X-rays cannot provide.
During a CBCT scan, the machine rotates around your head, similar to a panoramic X-ray, but it captures hundreds of images from different angles. A computer then assembles those images into a 3D model. This allows a specialist to view cross-sections of your jaw, measure bone density, and map the exact location of nerves and sinuses [1].
CBCT is used for implant planning (to confirm there is enough bone for the implant post), evaluating impacted wisdom teeth near the nerve canal, diagnosing complex root canal anatomy, and preparing for jaw surgery. The European Federation of Organisations for Medical Physics (EFOMP), the European Society for Radiotherapy and Oncology (ESTRO), and the International Atomic Energy Agency (IAEA) have published quality control protocols specifically for CBCT to ensure image quality and patient safety [1].
Radiation from a CBCT scan is higher than a standard dental X-ray but still much lower than a medical CT scan of the head. A typical dental CBCT delivers roughly 0.03 to 0.20 mSv depending on the field of view and the machine settings [1]. It is important to note that CBCT has received FDA clearance (through the 510(k) pathway, which means the FDA determined it is substantially equivalent to existing legally marketed devices) for dental use. Your specialist should use the smallest field of view that answers the clinical question, following the ALARA principle (As Low As Reasonably Achievable) to minimize your dose [2].
Practical Details: Frequency, Safety, and Who Needs Which Type
How often you need X-rays and which type you receive depends on your age, oral health history, and current symptoms.
How Often Are Dental X-Rays Taken?
The American Dental Association provides general guidelines based on patient risk level [3]. Adults with no recent cavities or gum disease typically need bitewing X-rays every two to three years. Adults with a higher risk of decay or active periodontal disease may need bitewings every six to 18 months.
Children and teenagers often need X-rays more frequently because their teeth and jaws are still developing. New patients of any age usually receive a more thorough set of images, often a panoramic X-ray plus bitewings, so the dentist can establish a baseline record.
Your dentist should explain why a specific X-ray is recommended. If you are unsure, ask what the image will show and how it will change your treatment plan.
Radiation Exposure and Safety
Dental X-rays involve very low levels of radiation. A set of four bitewing X-rays exposes you to roughly 0.005 mSv. A single panoramic image is about 0.01 to 0.03 mSv. Even a CBCT scan typically falls below 0.20 mSv [1] [3].
To put this in perspective, a round-trip cross-country flight exposes you to about 0.03 to 0.04 mSv from cosmic radiation at high altitude. The average American receives about 3.1 mSv per year from natural background sources. Dental X-rays add a very small fraction to that total.
Modern dental offices use digital sensors, which require significantly less radiation than older film-based systems. Rectangular collimation, a technique that narrows the X-ray beam to match the size of the sensor, can further reduce the dose by up to 60 percent compared to round collimation [5]. A lead apron may be draped over your torso, and a thyroid collar may be placed around your neck, to further reduce exposure. Pregnant patients should inform their dentist. While the radiation dose is very low, dentists often postpone non-urgent X-rays until after delivery as a precaution [3].
X-Rays for Children and Pregnant Patients
Children are more sensitive to radiation than adults, so pediatric dental offices adjust the settings to deliver a lower dose. Bitewing X-rays help detect cavities in baby teeth, which can affect the developing permanent teeth underneath. Panoramic X-rays help orthodontists assess how permanent teeth are developing and whether there is enough room for them to emerge [3].
For pregnant patients, the American Dental Association states that dental X-rays with appropriate shielding are considered safe when necessary for diagnosis [3]. However, many dentists prefer to wait until after delivery for routine X-rays. If you are pregnant and have a dental emergency, such as an abscess or severe pain, your dentist may determine that the benefit of taking an X-ray outweighs the very small risk.
What to Expect During Each Type of Dental X-Ray
Dental X-rays are quick and painless, and no special preparation is needed in most cases.
Bitewing and Periapical X-Rays (Intraoral)
For bitewing and periapical images, a dental assistant places a small sensor or phosphor plate inside your mouth, positioned next to the teeth being imaged. You bite down gently on a holder to keep the sensor in place.
The X-ray machine is positioned against your cheek, and the assistant steps behind a barrier or wall. You hear a brief click or beep. The exposure lasts less than a second. The assistant then repositions the sensor for the next image. A full set of four bitewings typically takes about five minutes.
Some patients find the sensor slightly uncomfortable, especially if they have a small mouth or a sensitive gag reflex. Let your dental team know. They can use a smaller sensor, adjust the angle, or give you a moment between images.
Panoramic X-Rays
You stand or sit in the center of the machine and bite down on a small plastic peg to position your jaw. The machine's arm rotates slowly around your head in a half-circle while you hold still. The entire process takes about 15 to 20 seconds.
Nothing is placed inside your mouth, which makes panoramic X-rays a comfortable option. You will need to remove eyeglasses, earrings, necklaces, and any removable dental appliances before the scan [3].
CBCT Scans
A CBCT scan is similar to a panoramic X-ray in setup. You sit or stand with your chin resting on a support, and the machine rotates around your head. The scan takes about 20 to 40 seconds, depending on the area being imaged.
You must remain very still during the scan. Even small movements can blur the 3D image. Remove all metal objects from the head and neck area before the scan [1]. After the scan, the software generates a 3D model that your specialist can rotate, slice, and zoom into. In many cases, the specialist reviews the CBCT data and discusses findings with you at the same appointment.
Cost Ranges and Insurance Coverage
Dental X-ray costs depend on the type of image, your location, and your provider. The figures below are approximate national averages and can vary significantly based on your geographic area, whether you have insurance, and the complexity of the case [4].
Bitewing X-rays (a set of two to four images) typically cost between $60 and $100. A full-mouth series of periapical and bitewing images generally ranges from $100 to $250. A single panoramic X-ray usually falls between $80 and $150. CBCT scans are the most expensive, typically ranging from $150 to $500, depending on the field of view and the complexity of the case [3] [4].
Most dental insurance plans cover routine bitewing X-rays once every 12 to 24 months and a panoramic X-ray once every three to five years. A full-mouth series is typically covered once every three to five years for new patients. CBCT coverage varies more widely. Some plans cover it when the scan is deemed medically necessary, such as for implant planning or evaluating impacted teeth. Check with your insurance carrier before the appointment if you are unsure about coverage.
If you do not have dental insurance, ask your dental office about self-pay pricing. Some offices offer a reduced fee or bundle X-ray costs into a new-patient exam package. You can also check cost estimation tools like FAIR Health Consumer to get a sense of typical charges in your area [4].
When to See a Specialist for Dental Imaging
Most routine dental X-rays are taken and interpreted by your general dentist. A specialist referral is needed when imaging requires advanced technology or expert interpretation.
Your general dentist may refer you to an oral and maxillofacial radiologist when standard X-rays show something unusual, such as a cyst, tumor, or an unclear finding in the jaw. These specialists have advanced training in interpreting complex images and can provide a detailed report to guide your treatment [2].
A CBCT scan is almost always ordered by or performed in the office of a specialist. Oral surgeons use CBCT to plan wisdom tooth extractions near the inferior alveolar nerve (the nerve that provides feeling to your lower lip and chin). Periodontists and prosthodontists use it for implant site assessment. Endodontists use it for complex root canal anatomy. Orthodontists may use it to evaluate impacted canines or assess jaw growth in three dimensions [1] [2].
You should consider asking for a specialist consultation if you experience persistent jaw pain with unclear X-ray findings, if your dentist suspects a growth or lesion in the jawbone, if you are planning dental implants in an area with limited bone, or if a previous root canal has not resolved and the tooth still causes symptoms. In these situations, advanced imaging and expert interpretation can make a significant difference in diagnosis and treatment planning.
Find an Oral and Maxillofacial Radiologist Near You
If your dentist has recommended advanced imaging or you need a specialist to interpret complex findings, you can search for a qualified oral and maxillofacial radiologist on the oral-radiology page. Entering your location will show you board-certified specialists in your area who can provide the imaging and interpretation you need.
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