IOPA Full Form: Intraoral Periapical X-ray

Intraoral means inside the mouth, and periapical means around the apex, the tip of the tooth root. An IOPA X-ray therefore shows the whole tooth and the bone at the tip of its root, which a bitewing does not.

Today it is usually taken digitally with a small sensor, often called an RVG; see RVG dental X-ray. Older practices may use a small film packet.

It is the standard picture for a painful tooth. It can show an abscess at the root tip, decay under a filling, a fracture, extra roots, bone loss from gum disease and the shape of the canals before a root canal. During treatment it is used to check the length of the canals, and afterwards to check healing. Our guide to root canal treatment explains where it fits.

For decay between back teeth, a different view is more usual; compare bitewing X-ray. To see how decay appears on film, ask your dentist to show you.

An OPG shows the whole upper and lower jaw in one picture but with less fine detail; see OPG full form. The overall range of films is in types of dental X-ray.

Dental X-rays use a very small dose of radiation, and the dentist uses them only when they are likely to change the treatment. Tell the dentist if you are pregnant before any X-ray.