Types of Dental X-Rays: Bitewing, Periapical, OPG and More
The DentiPoint Team · 30 October 2026 · 6 min read
The main types of dental X-rays are bitewing, periapical and occlusal images, which are taken inside the mouth, and the OPG (panoramic), cephalometric and CBCT images, which are taken outside it. Each answers a different clinical question, so choosing the right one comes down to what the dentist needs to see.
This guide is for dental teams and practice managers. It explains what each radiograph shows, when it is used, how often to repeat it and how to store the images. It also says plainly what DentiPoint does and does not do with images, so you can check it against your needs. It links to our guides on dental record keeping and dental charting.
What are the types of dental X-rays?
There are two groups. Intraoral radiographs place the sensor or film inside the mouth and give fine detail of teeth and nearby bone. Extraoral radiographs use a machine that moves around the head and show a wider view of the jaws, joints and skull. Most routine dentistry uses the intraoral group.
| Type | Group | What it shows | Typical use |
|---|---|---|---|
| Bitewing | Intraoral | The crowns of upper and lower back teeth together, and the bone crest | Decay between teeth, bone levels, existing restorations |
| Periapical | Intraoral | One or two whole teeth, from crown to root tip and surrounding bone | Infection at the root, root canal work, trauma |
| Occlusal | Intraoral | A larger view of the floor of the mouth or the palate | Salivary stones, unerupted teeth, jaw lesions |
| OPG (panoramic) | Extraoral | Both jaws, all teeth and the joints in one image | Wisdom teeth, general survey, orthodontic and implant planning |
| Cephalometric (ceph) | Extraoral | A side view of the skull and facial profile | Orthodontic assessment of growth and jaw relationships |
| CBCT | Extraoral | A three-dimensional image of a defined volume | Complex implant, surgical or endodontic cases |
What are the four main types of dental radiographs?
The four types most practices use every week are bitewings, periapicals, OPGs and cephalometric images. Occlusal and CBCT images are used less often, for particular cases. A practice that takes the first four well will cover almost all routine diagnosis, treatment planning and orthodontic work.
Is a periapical a bitewing?
No. A bitewing shows the crowns of the upper and lower teeth on the same image and is used to find decay between teeth. A periapical shows one or two teeth in full, from crown to root tip, and is used to look at the root and the bone around it. They are taken differently and answer different questions.
Many patients have both over time: bitewings at routine reviews and a periapical when a specific tooth is painful or needs root treatment.
What is an OPG, and when is one needed?
An OPG, short for orthopantomogram and also called a panoramic radiograph, is a single extraoral image of both jaws, all the teeth and the joints. It is used when the dentist needs the whole picture, such as assessing wisdom teeth, planning dentures, implants or orthodontics, or surveying a mouth with many problems.
An OPG is not a substitute for intraoral images when fine detail is needed. The Faculty of General Dental Practice’s selection criteria note that intraoral films outperform panoramic images for finding decay, gum disease and root-tip disease, so an OPG should be chosen for the question it answers well rather than as a routine extra.
What is an OPG and ceph?
An OPG and ceph is a pair of extraoral images commonly requested together for orthodontic assessment. The OPG shows the teeth, the developing teeth and the jaws from the front. The cephalometric image, or ceph, is a side view of the skull that lets the clinician measure how the upper and lower jaws relate and how the teeth sit on them.
What is a CBCT scan, and is it routine?
Cone beam computed tomography, or CBCT, produces a three-dimensional image of a limited area. It is not a routine check-up image. It is used where a flat image cannot answer the question, such as the position of a nerve before implant placement, or a complex root canal problem. It must be justified case by case.
How often should dental X-rays be taken?
There is no set number of X-rays per year. How often depends on the patient’s caries risk and the clinical question. Bitewing intervals are the best defined: the FGDP table, reproduced by the US Food and Drug Administration, suggests shorter intervals for patients with active decay or higher risk, and much longer ones for patients at low risk.
In the UK, radiography is also governed by the Ionising Radiation (Medical Exposure) Regulations 2017, which require every exposure to be justified and recorded. In practice that means three habits:
- Justify each image against a clinical question before it is taken.
- Record the reason and the findings in the notes, every time.
- Keep doses as low as reasonably practicable, using the smallest field and the right technique.
Rules differ in the US, Australia and elsewhere, so check the requirement of your regulator before setting a protocol.
Can a dentist send X-rays to another dentist?
Yes, with the right consent and safeguards. Images are part of the patient’s record, so a dentist can usually share them with a colleague or specialist for a referral or a second opinion, and a patient can usually ask for a copy. Send them securely, send only what the other clinician needs, and note the transfer in the record.
Data protection law applies to dental images like any other health data. Our guide to dental practice GDPR and patient data covers consent and retention in more detail.
How should a practice store dental X-rays?
Store each image against the right patient, the right tooth and the right date, in the same record as the notes and charting. An image that cannot be found, or that sits on a separate machine, is a risk at an inspection and a delay at the chair. Back it up with the rest of the record and keep it for the retention period that applies to you.
What does DentiPoint do with dental images?
DentiPoint stores and shows images. You can upload bitewings, periapicals, OPGs, CBCT files and photographs to the patient record, link them to teeth, and view them in the chart. They sit next to the notes, the dental chart and the treatment plan on the patient record.
It does not capture images. It has no link to X-ray sensors or machines, and it does not include a DICOM viewer, so you take the image with your existing imaging equipment and then upload it. If you need capture or DICOM review, keep your imaging software alongside it.
Frequently asked questions
What is the difference between intraoral and extraoral X-rays?
Intraoral images are taken with the sensor inside the mouth and give detailed views of teeth. Extraoral images are taken with the sensor outside the mouth and show the jaws and skull more widely.
Which X-ray shows decay between teeth?
A bitewing is the usual choice, because it shows the contact points between neighbouring back teeth, where decay often starts out of sight.
Is a dental X-ray safe?
Dental X-rays use a low dose, and regulations require each one to be justified and kept as low as reasonably practicable. The dentist weighs the benefit of the information against the exposure each time.
Can DentiPoint take X-rays?
No. DentiPoint holds the images you upload and links them to teeth. Capture stays with your imaging equipment.
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