The Real Truth About Dental X-Rays

In order to ensure that are teeth and supporting structures are healthy and free of disease, every person will be required to have dental x-rays at some point in their lives. For this reason, it is helpful to know a little bit about them – how safe they are and how they work. Dental x-rays, also known as radiographs, are utilized by dentists and dental specialists for a wide variety of purposes. These diagnostic tools can be used to assess the development and health of teeth, diagnose disease processes in the teeth and oral cavity and assist in many dental procedures such as endodontics (root canal procedures) and oral surgery.

Dental radiographs are a necessary and crucial part of dentistry and in maintaining a healthy and disease free oral cavity. This short guide will take you through the basics of dental x-rays, how they work as well as safety considerations.

What are dental x-rays?

Dental x-rays function just like any other type of x-ray. They involve taking a special sort of picture, called a radiograph. Since dental x-rays focus on the mouth, the set up for the x-rays differ from x-rays taken on different parts of the body. There are two main types of dental x-rays: intraoral and extraoral.

With an intraoral x-ray, which is the most common type of dental x-ray, the radiograph is taken from inside of the patient’s mouth. These images are imperative in helping the dentist to identify any issues that the patient may have that are invisible to the naked eye. These x-rays can also assess the health of the patient’s surrounding and supporting structures within the oral cavity.

By contrast, an extraoral x-ray is a radiograph that is taken from outside of the mouth. The focus on these x-rays is usually the jaw or the skull, although they also show the teeth. While the extraoral x-rays can’t show as much detail on the teeth as an intraoral x-ray, they can identify other issues such as how the patient’s jaws and teeth are developing, whether any of their teeth are impacted and the presence of any abnormalities within the patient’s supporting bone.

Recent developments have offered dentists an alternative to tradition film x-rays. With digital imaging, dental radiographs are sent to a computer and visible on a computer screen rather than needing to be developed in a darkroom like traditional dental x-rays. One of the benefits of digital radiographs is that it allows your dentist to see the x-ray immediately rather waiting several minutes during developing. It can also be used to enhance and enlarge images so they can be seen more clearly.

Dental x-rays are typically taken during dental check-up appointments approximately every six to twelve months. Extraoral radiographs such as panoramic radiographs are usually taken less frequently, approximately every three to five years. If a patient is experiencing pain in a particular area, or the patient has a history of disease in a certain area, additional x-rays may be needed to help identify the problem or observe an area in greater detail.

Dental x-rays are considered indispensible by dentists due to the fact that many disease processes that occur inside the oral cavity are not visible by sight alone. Dental radiographs allow the dentist to see any disease processes that are occurring between the teeth, below the outside layer of the teeth and below the gum tissue. Examples of this may include: decay between the teeth, any cysts, various types of tumors, gum disease and infections of the jaw. It is important to diagnose these issues early on so that they can be treated before they become a larger issue

The safety of dental x-rays

The discussion will now turn to the safety of dental radiographs. Many people worry that dental x-rays are unsafe due to an excessive amount of radiation exposure.

It is important to point out that there are two sides to this debate, and we will take a look at both of them now.

In many ways, dental x-rays are perfectly safe as they only require the patient to be exposed to a very small amount of radiation. We are often exposed to greater concentrations of radiation in our everyday lives, often because of cosmic radiation or radioactive elements that are naturally occurring. Dental x-rays expose you to less radiation than many other types of medical x-rays, including x-rays of the lower and upper gastrointestinal tract.

Radiation can be measured by a unit called a millisievert (mSv). To give an example, a full-mouth series of dental x-rays is estimated to expose a person to 0.0150mSv. In contrast to this, in the United States, the average amount per year of radiation from natural sources that a person is exposed to is 3.6mSv. The international standard for the Maximum Permissible Dose is 50mSv per year. In other words, this is the maximum amount of radiation a person can be exposed to over a period of time with little or no injury. This helps to put the radiation of dental x-rays into perspective.

However, this is not to say that we should not be careful with dental xrays. Exposure to any sort of radiation needs to be carefully considered. This is why pregnant women may be advised to refrain from dental x-rays until after their first trimester except on an emergency basis. In some cases, a mother’s dental infection could be a greater risk to an unborn baby than a dental x-ray. In these cases, extra shielding over the mother’s stomach is helpful as well as only taking necessary radiographs while pregnant. A leaded thyroid collar and the ‘As Low as Reasonably Possible’ principle should be applied to help limit the amount of radiation that the pregnant woman is exposed to.

Although dental x-rays emit very small doses of radiation, cells can still be damaged by many small doses over a period of time. It is important to realize that regardless of their benefits, certain precautions should be taken to decrease the amount of exposure that a patient is subjected to.

Listed below are many changes that have taken place in recent years to decrease the amount of radiation exposure to patients:

  • Decrease the X-Ray Dose — Limiting the dose is the most effective way for dentists to keep radiation levels low for their patients. The cone that
    is used to focus the x-rays helps to decrease the amount of radiation and limits the exposure area to only a few inches in diameter.
  • “Faster” film — Newer, faster types of x-ray film requires less patient exposure to get even better results than second or third generation film.
  • Digital radiography — Perhaps the biggest and most exciting advancement in the area of dental radiography is the development and widespread use of digital radiography.In addition to the countless other benefits such as increased speed, ease of use and increased diagnostic ability, the use of digital X-rays also reduces radiation by as much as 80% in comparison to traditional x-rays.
  • Safety Regulations — Regulatory agencies require certain standards are upheld to ensure that radiographic machines are accurate and safe.
  • Lead shields — Lead lined aprons are utilized to cover all areas of the body that may be exposed to scatter radiation which is unintended excess radiation that may occur during a dental x-ray. Although this is an added precaution, most modern dental radiographic machines produce very little stray radiation.
  • Limited use of X-rays — Dentists strive to only take dental X-rays when it is necessary for a complete and accurate dental evaluation or diagnosis.

The frequency of dental x-rays varies from office to office and patient to patient. It is generally expected to receive check-up radiographs annually with a new full-mouth series of x-rays every three to five years. The necessity for dental radiographs varies depending on the patient’s history of dental disease, age, and symptoms. As a dental patient, it is important to speak to your dentist with any concerns regarding dental radiographs.

In summary, the benefits of dental x-rays are well known. This diagnostic tool allows dentists to uncover common problems such as cavities, gum disease and oral infections. Radiographs allow the dentist to see inside of the tooth and below the gum tissue. Without the benefit of x-rays, more dental diseases would progress leading to more pain for patients, greater loss of teeth and a higher financial burden to the patient.