Imaging of the jaws

Abstract

Introduction The mainstay of dental imaging has traditionally been the intraoral images called periapicals and bitewings, which for many years were made with film that was wrapped in a protective packet. Today these images are taken using small detectors or sensors that are placed inside the patient 's mouth. The first digital intraoral solid-state detector, a charge-coupled device (CCD), was introduced in 1997. These detectors are directly attached to the computer by a wire and give an almost instantaneous image on the computer monitor (Fig. 1). This provides huge savings in time compared with the traditional wet processing needed for films as well as for the ability to manipulate the image and change its brightness and contrast. In addition, because the images appear on a monitor within the operatory it allows for instant feedback to the operator and also the patient. Several manufacturers are now using complementary metal oxide semiconductor technology for their detectors, as it is less expensive to produce than CCD technology. In dentistry these types of detectors are often referred to as “sensors” to differentiate them from an alternate digital intraoral detector, photostimulable phosphor (PSP) plates. PSP plates are thinner and more flexible than the solid-state sensors and are often tolerated better by the patient. They are the same size as traditional intraoral film packets and can be used with the same positioning devices without modification. Exposure to x-rays produces a latent image within the plate in the form of stored energy, which is released when the plates are “processed” by laser light in the manufacturer 's scanning device or reader. The readers are often small enough that they can be placed in the dental operatory (Fig. 2). The image, therefore, like film is not instantaneous as this is a 2-step process. However, once placed in the reader the images can appear on the computer monitor in as little as 3 seconds. Some dental offices still use film-based imaging