Bitewing dental X-rays are a type of dental radiograph that provides a detailed view of the upper and lower back teeth (premolars and molars) in a single image. These X-rays are called "bitewing" because the patient bites down on a small tab or wing-shaped device that holds the X-ray film or sensor in place, allowing for a clear and consistent view of specific areas of the mouth.

Here's how bitewing dental X-rays work and their primary purposes:

How Bitewing X-Rays Work:

1. Preparation: Before taking bitewing X-rays, a dental professional will position a small, wing-shaped X-ray holder or sensor between your upper and lower teeth on one side of your mouth. You'll be asked to bite down gently to hold it in place.

2. X-ray: A focused X-ray beam is directed at the X-ray holder or sensor. This beam passes through your teeth and strikes the X-ray film or sensor, creating an image.

3. Image Development:The X-ray image is processed, either electronically (if using digital X-rays) or chemically (for traditional film X-rays), to produce a visible image of your teeth and supporting structures.

Primary Purposes of Bitewing X-Rays:

1. Detecting Cavities: Bitewing X-rays are commonly used to detect cavities (dental caries) between teeth, in areas not visible during a visual examination. They provide a clear view of the contact points between adjacent teeth, where cavities often develop.

2. Monitoring Gum Health: These X-rays can show changes in the bone structure that may indicate gum disease or bone loss around the teeth.

3. Assessing Restorations: Bitewing X-rays are helpful for evaluating the fit and integrity of dental restorations like fillings, crowns, and bridges.

4. Tracking Growth and Development: In paediatric dentistry, bitewing X-rays are used to monitor the development of permanent teeth and assess orthodontic treatment progress.

5. Treatment Planning: Bitewing X-rays are essential for creating treatment plans, whether it's for addressing cavities, gum disease, orthodontic needs, or other dental issues.

6. Preventive Care: Regular bitewing X-rays, as part of routine dental check-ups, help catch dental problems in their early stages, allowing for less invasive and more effective treatment.

Bitewing X-rays expose patients to a minimal amount of radiation, and the benefits in terms of early diagnosis and prevention of dental issues typically outweigh the risks. The frequency of bitewing X-rays depends on your dental health and risk factors, but they are typically taken at regular intervals during routine dental check-ups, usually once a year or more frequently if necessary. If you have concerns about X-rays or radiation exposure, it's a good idea to discuss them with your dentist, who can explain the necessity and safety measures involved in dental radiography.

Safety with Bitewing X-Rays

Bitewing X-rays, like other dental X-rays, expose patients to a small amount of radiation. The amount of radiation in a bitewing X-ray is relatively low compared to many other medical imaging procedures. The dose of radiation from a single bitewing X-ray is measured in microsieverts (µSv), which is a very small unit of radiation exposure.

In Australia, dental professionals take precautions to ensure the safety of patients when using X-rays. They follow the principles of ALARA, which stands for "As Low As Reasonably Achievable." This means that they aim to keep radiation exposure to the minimum necessary to obtain the diagnostic information needed for your dental care.

The exact radiation dose from a bitewing X-ray can vary depending on several factors, including the type of X-ray equipment used, the settings chosen, and the specific technique employed by the dental professional. However, on average, a single bitewing X-ray typically exposes a patient to a radiation dose ranging from 0.005 to 0.01 millisieverts (mSv). To put this in perspective:

- The average annual background radiation dose from natural sources in Australia is about 1 to 2 mSv per year.

- A chest X-ray typically delivers a radiation dose of approximately 0.1 mSv.

- A cross-country flight can expose you to around 0.03 to 0.05 mSv of cosmic radiation.

Given the low dose of radiation involved in bitewing X-rays, they are considered safe for most patients. However, dental professionals take precautions to minimise radiation exposure:

1. Lead Aprons and Collars: Patients are often provided with lead aprons and collars to shield their bodies from unnecessary radiation exposure.

2. Digital Radiography: Many dental practices in Australia use digital X-ray technology, which requires less radiation compared to traditional film X-rays and allows for precise control of exposure settings.

3. Risk Assessment: Dentists carefully evaluate the need for X-rays based on a patient's dental history, symptoms, and risk factors.

4. Pregnant Patients: Pregnant patients are usually advised to postpone non-emergency X-rays to minimise foetal exposure.

5. ALARA Principle: Dentists adhere to the ALARA principle to ensure that X-rays are used judiciously and only when necessary for diagnosis and treatment planning.

It's important to discuss any concerns you may have about radiation exposure with your dentist. They can provide information about the necessity of X-rays in your specific case and address any questions or worries you may have. In general, the benefits of diagnostic X-rays in dentistry far outweigh the minimal associated risks when appropriate safety measures are followed.