What types of dental x-rays are there?

Dental X-rays are useful for diagnosing problems in the mouth and for performing some treatments. There are different types and we detail them here.

Last update: August 26, 2021

In dental practice, dental radiographs are often they are necessary to arrive at a diagnosis or carry out a treatment. It is a complementary method that provides detailed data that otherwise could not be known.

This technique uses X-radiation to obtain images of the hard and soft structures of the oral cavity. There are various procedures, which are chosen according to the needs of each clinical case. Keep reading and learn more about it.

What are dental x-rays?

Dental x-rays are images of teeth and oral structures obtained with the use of X-rays. This radiation is capable of penetrating and passing through the body to form an image on a film or screen.

During the process, the rays are absorbed to a greater or lesser extent by the different tissues. Depending on the amount of radiation that reaches the radiographic film, it will be the color of each image on the developed plate.

Soft tissues, with high organic content, they are observed of a darker and greyish coloration, and the air of black color. In contrast, denser structures (such as bone, tooth enamel, and metal fillings) appear white. This is because they block most of the rays.

The choice between one type of dental radiography or another is made based on the individual characteristics of the patient. Still, they are grouped into two broad categories:

  • Intraoral: X-ray film is placed inside the mouth.
  • Extraoral: the plaque goes outside the oral cavity.
Dental X-rays facilitate the diagnosis and treatment of a wide variety of diseases that compromise dental health.

What are dental x-rays for?

Dental X-rays are capable of provide data on the state of the internal tissues of the mouth. Thus, it is possible to detect pathologies and conditions that cannot be seen with the naked eye. Taking X-ray films in the mouth allows us to observe some of the following conditions:

  • Interproximal or deep caries.
  • Leaked or misfit seals.
  • Abscesses
  • Cysts
  • Tumors
  • Dental fractures and trauma.
  • Loss of bone
  • Developmental abnormalities.
  • Retained teeth or teeth that have not yet erupted.

They are also useful before performing some procedures, since they reveal the state of the teeth and the bone that surrounds them. In fact, they are essential before performing surgery, endodontics and prior to implant placement.

In addition, are suggested before beginning orthodontic treatment. These allow measurements and projections to be made to choose the most appropriate treatment according to the patient's needs.

Among other things, they are used during the performance of certain therapies, since they allow to visualize if it is proceeding correctly or if it is necessary to correct a maneuver.

Types of intraoral dental radiographs

Intraoral dental radiographs are those that are taken by placing the film inside of the oral cavity. Many times, it is the same patient who holds the plate during the study.

These techniques are performed in a traditional way with a minimal amount of X radiation. However, there are now digital methods that allow these same images to be obtained on a computer. In these cases, the radiation used is less.

Periapical dental radiographs

It is a small dental X-ray that allows to observe the totality of one or two dental elements. With this technique it is possible to contemplate in detail the complete crown, the root of the dental element and the tissues that surround it.

Its objective is to assess the dental structure, observe the pulp space, root canals and supporting tissues. At the same time, it allows detecting problems or infections located in the bone thickness close to the tooth.

The x-ray films for this type of study are available in one size for use in adults and smaller proportions for use in children. The radiation used is minimal.

In some cases, to carry out a detailed study of the state of the patient's dental and bone tissues, a complete series or full set. It involves taking 14 or 20 individual periapical dental radiographs for each area of ​​the mouth, in order to carefully observe each sector of the oral cavity.

Bitewing X-ray

This technique, also called «interproximal» or bitewings, is used to obtain a complete image of the patient's upper and lower dental crowns. For its realization the patient is made to bite off a small flap attached to the radiographic film.

With this study it is possible to observe the bite line of the teeth and the proximal relationship of the crowns. Therefore, they are useful to diagnose proximal cavities, which are those that are located between the teeth.

Occlusal dental radiographs

The occlusal or palatal radiographs use a larger plate than the previous ones. The film is placed between the upper and lower arch, and the patient is made to bite.

It manages to capture the position of the teeth in the arch. In the same way, it allows us to observe the included teeth, which are those that have not erupted in the jaws. Thus, its position is determined.

They are used less frequently, and can now be replaced with other newer and more comfortable studies for the patient.

Types of extraoral dental x-rays

As we have already mentioned, these are dental radiographs in which X-ray film is placed outside the mouth of the patient. Below we mention the most used.


The orthopantomography, also called "panoramic radiography", is one of the most used in dentistry. It allows you to see the entire mouth, jaws and teeth in one shot.

It provides a large amount of data with minimal radiation and with a simple procedure. For this reason, it is quite common that it is requested at the beginning of the reviews or in the first consultations.

To carry it out, a special device is used that rotates around the patient's head. The film is placed outside the oral cavity, making it a very comfortable and simple technique.

With this test, dentists can identify pathologies and anomalies located in the bone thickness or in the dental roots. Too allows you to see teeth that have not erupted and assess the condition of the jaws and joints.


Teleradiography, also known as "cephalometry" or "lateral skull radiography," is a type of study used before starting orthodontic treatments. Shows a profile view of the face, which allows the exact intermaxillary relationship to be observed.

In passing, it helps to assess the state of the skull bones, their growth, the proportions and the relationships of the bone structures with each other.

Dental CT

Dental computed tomography (CT) is similar to those used in general medicine. It consists of taking hundreds of images from different angles of the patient's mouth.

They are processed on a computer, where a virtual image is generated in the 3 dimensions of the mouth. On this study, the dentist can make sections, mark specific points and study the oral cavity in detail.

Radiation Impact of Dental X-rays

When X-radiation doses exceed certain levels, acute and immediate damage to human health can occur. Skin burns or acute radiation syndrome are some examples.

But this does not happen with dental X-rays, since they use a minimal amount of radiation and do not generate any immediate impact on health. The low doses used for dental plaques do accumulate on the tissues.

Accumulated radiation throughout the body can cause long-term effects. However, with modern technology this risk is minimal. Anyway, these tests They should only be carried out in those cases whose use is justified. In this way, subjecting the patient to unnecessary radiation exposure is avoided.

The dentist is the ideal professional to know what situations warrant the use of these studies. In addition, the ideal is to protect patients, especially children and adolescents, with leaded aprons that cover highly radiosensitive areas, such as the thyroid gland and reproductive organs.

In the case of pregnant patients, its use is not recommended, especially in the first weeks of gestation, during the formation of the baby's organs.

While there is evidence that the minimal amount of radiation used is safe for both mother and fetus, it is best to avoid them. If this is not possible, and the study cannot be postponed, the dentist will take the necessary steps to care for the mother and baby.

In this sense, it is necessary to protect the abdomen and neck area with leaded aprons and collars to reduce the amount of radiation that penetrates. If possible, it is best to do the study with digital equipment to significantly decrease exposure.

The radiation from dental X-rays is minimal, so there are no health risks. Even so, it is necessary to reserve its use only for strictly necessary cases.

What You Should Know Before Getting Dental X-rays

As you have seen, dental X-rays are useful both for diagnosis and for the performance of some dental treatments. The X-radiation they use is minimal and does not pose a health risk. In addition, doing them is simple and comfortable.

In any case, its use should be limited only to cases where it is really necessary. And while no special preparation is necessary, the dentist may request to remove the metallic objects present in the area to be irradiated, such as earrings or piercings.

However, if the woman is pregnant or suspects that she may be pregnant, it is essential to notify the professional to take the appropriate protection measures. If possible, go to clinics with modern equipment, since digital radiology devices reduce radiation exposure.