An IOPA, or intra-oral periapical X-ray, is a small Dental X-ray that shows one or two teeth from the crown down to the tip of the root and the bone around it. It is the standard image for a toothache, a root canal, or a suspected infection. It takes a few seconds, the dose is very low, and in India it usually costs a few hundred rupees per image.
If your Dentist says "let us take an IOPA", the term can sound technical. This guide explains what it is, how it is taken, what it can and cannot show, what affects the cost, and when something else, such as an OPG, is a better choice.
What IOPA Means
IOPA stands for intra-oral periapical. Intra-oral means the sensor or film is placed inside the mouth. Periapical means around the tip, or apex, of the tooth root. The image therefore shows the whole tooth and the bone surrounding the root tip, which is where many problems start.
What It Shows
Infection or an abscess at the tip of a root.
The length, shape, and number of roots.
Decay that has reached deep into the tooth.
The quality of a root canal filling.
Bone loss around a tooth from gum disease.
Cracks or fractures that are visible at the root.
The development of a child's teeth.
It shows these in much finer detail than an OPG, because the beam and the sensor are close to a small area.
What It Does Not Show
An IOPA covers only a small area, so it does not give an overview of both the jaws or the position of wisdom teeth. Like all flat images, it can hide structures that overlap, and it cannot show the thickness of bone or the course of a nerve. When those matter, an OPG or a 3D scan may be advised. How an OPG compares with a CBCT explains when to step up.
How the Procedure Works
The Dentist or technician places a small sensor or film in your mouth, held by a plastic holder you bite on.
You are asked to stay still and breathe normally.
The X-ray tube is positioned outside your cheek, and the exposure takes a fraction of a second.
The image appears on screen within seconds if a digital sensor is used.
Additional images are taken for other teeth if needed.
Most people find it painless. The sensor can feel hard against the gum, and people with a strong gag reflex may find the back teeth difficult. Breathing slowly through the nose helps, and you can tell the operator if you need a break.
Radiation Dose
A single digital IOPA delivers roughly 1 to 8 microsieverts, depending on the machine and settings, which is less than the natural background radiation you receive in a day, about 6 to 7 microsieverts. Digital sensors use less than older film. Because each image is small and the beam is directed at a limited area, the dose is among the lowest in Dental imaging. The facts and myths about Dental radiation puts these numbers in context, and how doses are kept low for children covers young patients.
Cost in India
Prices vary by city, clinic, and whether the image is digital. A single IOPA commonly costs ₹100 to ₹500. Many clinics include it in an examination or charge a package price when several are needed for a root canal. When comparing, ask:
Is the price per image, or for a set?
Is the image digital, and will I get a copy?
Is a written report included, or only the image?
Are images for the root canal itself, during and after treatment, included in the treatment fee?
The reasoning is the same as for OPG prices, as why the same X-ray can cost very different amounts explains.
IOPA, Bitewing or OPG?
| Image | Area covered | Best for |
|---|---|---|
| IOPA | One or two whole teeth, crown to root tip | Toothache, root infection, root canal |
| Bitewing | Crowns of back teeth, both jaws together | Cavities between teeth, early bone loss |
| OPG | Whole mouth and jaws | Overview, wisdom teeth, missing teeth |
What a bitewing shows describes the difference in detail.
When You Might Need More Than One
A single tooth may need two IOPA images from slightly different angles, because overlapping roots can hide a problem. During a root canal, images are commonly taken to measure the canal length, to check the filling and sometimes at follow-up. These are small doses, but your Dentist should be able to explain why each one is needed.
Before You Go
Tell the Dentist if you are or may be pregnant. What is considered safe explains the approach.
Bring any earlier X-rays.
Remove any removable denture or retainer from the area if asked.
Mention a strong gag reflex, so the operator can adjust.
Frequently Asked Questions
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An intra-oral periapical X-ray: a small image taken with a sensor or film kept inside the mouth that shows one or two teeth and the bone around the root tips.
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Usually a few hundred rupees per image, varying by city and clinic. Ask whether the price is per image and whether you get a digital copy.
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Yes. The dose is very low, and it is taken only when the Dentist needs the information.
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An IOPA shows a few teeth in fine detail. An OPG shows the whole mouth in less detail. They answer different questions.
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Yes, it is one of the best images for finding infection at a root tip, though a 3D scan may be advised in difficult cases.
