According to the American Dental Association, most dental practices are using some form of digital radiography today, whether it’s for taking a full set of x-rays, panoramic images, or a cone beam CT. Digital radiographic imaging has numerous benefits: lower x-ray exposure for both patients and clinicians, elimination of processing chemicals, and they are easier to store, copy, and share than conventional x-rays. Another advantage is that digital images can be “edited” or manipulated with software to enhance color and brightness, zoom in or enlarge areas, and otherwise improve image accuracy. Since these images are being used to diagnosis and treatment plan, it’s important that image quality is consistently accurate.
Improving and Maintaining Image Quality
An important goal with digital imaging is to minimize x-ray exposure. If images are too light or too dark, retakes expose patients to extra x-rays. Exposure time is adjustable, necessary for imaging different tissue densities, which are affected by the physical size, anatomy, and health of individual patients. Certain other “technique factors,” along with correct positioning of the x-ray tube, are essential to obtain the highest quality images.
Technique factors include three variables: kilovolts (kV), milliamps (mA), and time. kV has to do with the penetration power of the x-ray. mA is controlling the volume of x-rays. Time is usually conveyed in seconds or milliseconds. These factors may vary by model, and staff using the technology needs to be familiar with the parameters. Technique factors also include the area of the mouth being imaged. The more dense the tissue is, the more technique factors required. In addition, the maxillary molar area requires the most exposure time and the mandibular anterior regions needs the least. While a 65-70 KVP exposure setting is recommended for Schick 33 intraoral sensors, is should be adjusted to address various technique factors.
Sensor and x-ray tube positioning are critical to avoiding retakes. Using ring guides, biteblocks, bite-wing tabs, and a paralleling device ensure stability of the sensors and appropriate proximity of the x-ray tube during the imaging process. The x-ray tube should be placed so that the beam doesn’t create or capture overlapping contacts, or get cut off by the edge of the tube, or cause foreshortening or elongation of the image. This takes practice, but is not a steep learning curve with the proper training/orientation. In addition to staff training offered by the manufacturer, Schick by Dentsply Sirona, there are many resources for refreshers, including lots of videos on YouTube.
Proper servicing and calibration, both by staff and the manufacturer on whatever schedule they recommend, is also important to image quality.
Schick by Sirona offers sensor placement tips for taking vertical bitewings, endodontic images, maxillary and mandibular anterior/posterior, horizontal and vertical bitewings, more accurately and comfortably for patients. Additionally, Schick 33 has “presets” and “me-sets” that give clinicians the ability to use default settings for general dentistry, endodontics, periodontics, or restorative dentistry as well as personalize them. Then Schick’s Image Enhancement System can be used to adjust image sharpness and contrast, giving the clinician complete control over image quality.