September 2010, Volume 6, Issue 8
Published by AEGIS Communications
Maximize the benefit of the next generation of CMOS-APS technology and unique design through proper technique.
Intraoral radiographs are at the heart of diagnostic dentistry, revealing interproximal decay, root fractures, and bone levels that might otherwise go unseen. For today’s modern dentist, the only choice for intraoral radiographs is a digital solution, allowing them to benefit from instantaneous images, lower radiation, and the ability to use full-screen images to discuss diagnosis and treatment options with their patients, not to mention removing the act of processing film and phosphor plate images that require excessive amounts of a clinician’s time as well as chemicals.
However, it is important to understand that benefiting from quality digital radiographs goes beyond the simple act of implementing a digital radiography solution in one’s practice. For the highest quality of digital images, consideration must also be given to the technique used—both in terms of proper positioning and correct radiation levels.
The Right Positioning System
To make the positioning of its sensors as easy and repeatable as possible, Schick designed and patented its adhesive bite tab holders to provide a unique solution that not only provides quality imaging, but also an unrivalled level of flexibility and patient comfort.
One of the industry’s best-selling digital radiography positioning systems, the Schick system is a disposable adhesive tab that utilizes aiming arms and rings. Available for vertical and horizontal bitewings as well as anterior and posterior periapical images, the adhesive tabs stick to a custom-fitted protective sheath covering the CDR Elite sensor. The adhesive tabs provide two key advantages:
- No addition whatsoever to the external dimensions of the sensor, which, in turn, has no adverse affect on the smooth, round edges and corners of the sensor to maximize comfort.
- Added flexibility. For patients with long posterior roots or who have difficulty accommodating the aiming arm for posterior periapical images, the position of the tab on the sensor can be changed to allow a quality image to be captured, without the clinician being forced to bisect the angle.
The Right Technique Factors
Each model of an intraoral x-ray generator is different, which can lead to confusion over the correct technique factors to be used. To apply the correct technique factors for the highest quality diagnostic images, it is important to be able to understand what is causing poor images.
The easiest technique factor error to recognize is the use of too much radiation, where the duration of radiation exposure is too long. When too much radiation is used, the more radiolucent parts of the patient’s anatomy (starting with the bone structure) will appear “burnt out.” This can commonly occur if the clinician has not reduced the radiation level either from a previous larger patient or from a previous image that required more radiation, such as moving from a molar to an incisor image. While overexposed images can be adjusted using software to improve their appearance, the simple solution is to reduce the exposure time/pulses on the intraoral x-ray generator.
Underexposure, where the duration of the exposure time is too short, is frequently harder to detect, yet is the most likely cause of an unsatisfactory digital radiograph. The use of too little radiation will normally still provide anatomic information, yet the image will appear noisy/grainy and “flat”—ie, lacking in contrast.
For many clinicians, diagnosing the problem with an underexposed image is not always easy, but there are a few simple clues beyond the general noise levels of the image which stand out:
- Visibility of the bitetab used to position the sensor. In a properly exposed image, this should be a very dark shade of gray, if not invisible.
- High noise levels in soft tissue regions, particularly behind the last molar tooth.
- Low contrast in the periapical region.
On older AC x-ray tube heads, the contrast can be improved by adjusting exposure time. As these units frequently have large steps between exposure levels (eg, going from three to four pulses is a 33% change in radiation), a decrease of one pulse can result in a greatly underexposed image. The impact of radiation increases can be improved by replacing the standard 8” x-ray cone with a 12” cone. The increased distance not only reduces the impact that one extra pulse has on density, but also improves the sharpness of the image by offering an improved focus of the x-ray beam.
While poor contrast is frequently attributable to insufficient exposure, DC heads with variable kV levels can be adjusted to improve the contrast levels. For example, a one-step increase in the kV setting from the default of 60 kV to 65 kV or 70 kV (depending on the unit’s capabilities) can further improve DEJ clarity and visibility of periapical anatomy.
Schick CDR Elite
Featuring Schick’s next generation CMOS-APS sensor technology, a robust design and the input of leading dental radiologists, CDR Elite sensors provide Elite image quality for bold bone tribeculation, crisp lamina dura and clear DEJ to meet all your imaging needs. CDR Elite also benefits from a bright, bold design for easy positioning and Schick’s unique cable replacement technology for maximum reliability and longevity. CDR Elite sensors are available exclusively through Patterson Dental Supply.
The preceding material was provided by the manufacturer. The statements and opinions contained therein are solely those of the manufacturer and not of the editors, publisher, or the Editorial Board of Inside Dentistry. The preceding is not a warranty, endorsement, or approval for the aforementioned products or services or their effectiveness, quality, or safety on the part of Inside Dentistry or AEGIS Communications. The publisher disclaims responsibility for any injury to persons or property resulting from any ideas or products referred to in the preceding material.
For more information, contact:
Patterson Dental Supply, Inc.