Dental radiographs are commonly called X-rays. Dentists use radiographs for many reasons: to find hidden dental structures, malignant or benign masses, bone loss, and cavities. Almost everyone who visits dentists has the experience of taking dental radiographs. Similar to other medical branches, radiography is used in dentistry to help diagnose oral diseases or tooth decay. Radiographs can help dentists to diagnose and determine the severity of dental cavities or caries. They also help to detect tooth decay even when the enamel still looks healthy or when tooth decay is obscured between the teeth or by the gumline. Dentists use dental radiographs to diagnose dental abscesses, periodontal disease, jaw and tooth fractures, and other maxillofacial deformities. Moreover, radiographs provide information to dentists about unerupted teeth.
Dental radiography includes traditional (analog) methods and digital technologies. The bitewing radiographs are used to diagnose dental caries. In bitewing radiography, a small of the film is placed in the mouth and near the teeth, and the patient should bite the paper cover to hold the film. Then the device is set and X-rays are emitted to the indented area. Digital images will be ready immediately and the radiographic film does not take more than a few minutes to be developed. The resulting image helps your dentist to choose the best treatment measures. Although the X-ray radiation dose is very low in analog radiography and very negligible in digital radiography, people should avoid overexposure to X-ray radiation. It is better to consult your dentist about how often you need to undergo dental radiography. As a precaution against overexposure to X-ray radiation, patients wear a special apron to protect their chest and abdomen during radiography.
A periapical radiograph is one that captures the whole of one tooth or a couple of teeth. This radiograph shows everything from the crown (chewing surface) to the root (below the gum line). The dentist may take at least four periapical radiographs during root canal treatment; the first image shows the tooth root conditions, the second one shows the length of the file or needle in your dental canal and helps the dentist to determine the length of the tooth root, the third image shows whether root fillers have completely filled the entire length of the root, and the final image can show the results and quality of treatment. The periapical radiography device can be found in any dental office, and its advanced models emit a negligible dose of X-rays.
The dentist and their assistance should take several radiographs from many patients during a day, whereas every patient is exposed to only a negligible dose of X-rays for a few minutes. Therefore, when older models of periapical radiography devices are used, the dentist and their assistance should stay behind a lead wall during the radiation. A full mouth survey requires at least 14 periapical radiographs.
Dental radiography in children
Dental radiography for children is the same as the procedure performed for adults. The only difference is the smaller size of the film to fit in a child’s mouth. In addition, the X-ray radiation dose used for children is lower than the dose for adults.
Panoramic radiograph (OPG)
A panoramic radiograph captures the entire mouth in a single image, including the teeth, upper and lower jaws, surrounding structures, and tissues. Panoramic images are usually taken by a special device in radiography centers. To take panoramic images, a rotating arm on the radiography machine makes a semi-circle around your head to record your mouth. Dentists usually prescribe panoramic radiography to detect jaw fractures caused by accidents or falling, diagnose maxillofacial tumors or cysts, and plan the treatment for orthodontics or wisdom teeth extraction.
Although you may be less willing to take bitewing radiographs, they can well show decay between teeth. Four bitewing radiographs are enough for the dentist to check decay between the back teeth. Since the maxillary and mandibular teeth on this image are similar to a butterfly wing, this type of dental radiograph is called “bitewing radiograph” or “bitewing X-rays”. Your dentist may request one or multiple bitewing x-rays during your annual check-ups.
Before undergoing an orthodontic treatment, you need to visit a radiography center to take a cephalometric image. Cephalometric images are used to check the growth of jaws, face, and skull. Moreover, they can well show the maxillofacial growth pattern. The cephalometric image taken before orthodontic treatments is called lateral cephalometric radiographs.