3-D imaging and endodontics: educated guess becomes scientific decision

by Harout Barsemian, DMD

As an endodontist, I was trained to get to the root of the problem. While this is literally my job and my passion, in the past it has also been a source of frustration. Conventional 2-D images did not provide enough data to make scientific decisions regarding diagnosis and treatment planning.

With some 2-D images, rather than diagnosing, it felt like I was just guessing. My recent investment in a 3-D medium field-of-view cone-beam scanner (Gendex GXCB-500) has changed my frustration into realization and enabled me to become a more conscientious practitioner.

An endodontic diagnosis depends upon many factors, such as the experience of the clinician, anatomical limitations such as thickness of the cortical bone, positioning of the apical abscess to the cortical bone, zygomatic bone and sinus and proximity of neighboring teeth. With 2-D X-rays, often these structures are superimposed on one surface.

Research in the endodontic field indicates that CBCT showed significantly more lesions (34 percent) than periapical radiography. In some infection cases, general dentists often delayed treatment due to lack of supporting evidence on a 2-D X-ray. With 3-D views, we can make an immediate scientific decision. For example, many endodontic patients who suffer from chronic sinusitis find that the ideology is really related to the teeth. Sadly, many have already given up on treating the problem and have learned to live with their post-nasal drip forever.

After implementing the cone-beam system, not a day passes when I take a scan that I don't find other, less obvious contributing factors. I find canals that were left untreated by previous practitioners; complicated canal systems and unusual anatomy; and other teeth or structures that need immediate attention outside of the field of interest.

Deciding whether resorption cases are interior or exterior sometimes became a guessing game that took several X-rays to determine if the damage was even repairable.

With software, such as Anatomage's Invivo5, it is much easier to establish if a tooth is cracked. The ability to colorize in this software makes detecting the crack, although still tricky, much easier. In trauma cases or root fractures, the 3-D scan clearly shows displacement or a bony fracture. In the case of calcified canals, I can acquire a mid treatment image with the CBCT and define the exact direction of the canal.

After diagnosis, all of the scientific evidence is vital for surgical confidence. Now, I feel more assured about my patients' safety. With the guesswork involved with 2-D X-rays, I endured the uncertainty of not knowing the proximity of anatomical structures. In the case of separated instruments, I can locate the exact position of the instrument for a less stressful surgery.

Cone-beam radiography helps me to avoid potential unwelcomed surprises during surgery. For example, one patient came to me with persistent swelling. While the post-op 2-D PA image showed healing (Figs. 1a and 1b), the cone-beam scan showed an area of very large infection extending to the inferior alveolar nerve with extensive cortical bone destruction (Fig. 2). This was vital pre-surgical information.

With another patient who was suffering from intense pain from a tooth that was heavily restored with a very large periapical rarification, I decided to do an apicoectomy to provide immediate relief. On a 2-D X-ray, all appeared to be simple (Fig. 3); however, because the problem was on a posterior tooth, I decided for safety sake to acquire a CBCT scan.

The 3-D view showed that the infection was so far in lingually (Fig. 4) that a very thick layer of cortical bone had to be removed, and the positioning of the inferior alveolar nerve was so coronal that paresthesia could also have resulted in this case.

Because of the scientific data gathered from the cone beam, I have begun to get referrals from forward-thinking colleagues. I put scans on CD and print out reports, so they, too, can have as much information as they need to provide the best care for their patients.

My scientific mind doesn't like to make guesses, even educated ones. Cone beam gives me the facts, so that I can accomplish my ultimate goal -- getting to the root of the matter, not by trial and error, but by using science and facts.


Cone Beam 3-D Imaging

Discover A New Dimension Of Predictability, Precision
Experience more advanced anatomical views by capturing 3-D images right in our office. we can achieve incredibly accurate, immediate assessments with the GXCB-500™, powered by i-CAT®.

The CBCT provides a considerable radiation reduction, in comparison to traditional CT scans.  treatment planing is possible with a clear diagnosis backed by visualization.

Better diagnostics in panoramic imaging begins with recognition of critical aspects of the patient's anatomy, especially focal areas. With the new 8500, focal detection is made possible by KINEMAGIC™ Articulated Motion Technology. This morphology-tracing feature precisely follows the patient's focal trough to ensure constant focus across the image. The result is a highly diagnostic image with consistent magnification.

Images from the new 8500 DDE are clear and sharp due in part to AEC -- Automatic Exposure Control, which detects the best radiographic exposure for a specific area as the x-ray is taken, yielding an image with optimum contrast. Utilizing the industry's smallest focal spot of 0.4mm also adds to the delivery of greater image quality.

Along with child and adult pan projections, Gendex added TMJ imaging to the new panoramic system. Both frontal and lateral TMJ projections are easy to capture. Plus these new views add to the system's value allowing dentists to take images that otherwise may be referred out.

Clinicians and patients alike can appreciate the new patient positioning devices. Easy-to-use leveractuated temple supports and improved bite guides help the team quickly and efficiently ensure better patient stability for more consistent imaging while providing increased patient comfort.

Gendex, known for its reliable and innovative imaging equipment, offers a wide variety of solutions for both general dentists and specialists. The company's strong history in x-ray manufacturing, along with a deep dedication to deliver products that meet the needs of dental professionals, have earned Gendex numerous awards from the dental community and design world



Efficient Processes in Practice
Remarkably Fast, Remarkably Accurate

  • Rapid 8.9 second scan time
  • Full 3-D reconstruction in less than 20 seconds
  • Benefit from distortion-free images to reveal critical anatomical details
  • Transition quickly from 3-D to 2-D panoramic with a mouse click - no need to switch sensors!



Targeted Treatments, Surgical Predictability

  • 360 degree, 3-D Scans capture oral and maxillofacial features
  • Standard "Jaw" Scan, 8 cm diameter x 8 cm height: Supports implant planning, endodontics, and surgeries
  • Extended Diameter Scan, 14 cm diameter x 8 cm height: Assists with TMJ evaluation and airway analysis



Implementation As Easy As 1-2-3-D

  • i-CATVision™ software included and freely shared
  • DICOM 3 compatible images easily exported to third-party applications



Remarkably Fast, Remarkably Accurate
The GXCB-500 provides powerful, instantaneous diagnostic and treatment planning tools that surpass the capabilities of conventional 2-D imaging. Now, we can rely on distortion-free images to reveal critical anatomical details.

An Amorphous Silicon Flat Panel Sensor delivers accurate images at a scan time of only 8.9 seconds and yields full, 3-D reconstruction in less than 20 seconds. Remarkably fast image acquisition lets us start treatment planning right away.




Targeted Treatments, Surgical Predictability
Capture anatomically accurate information to assist in diagnosis, planning and treatment. Digitally replicate mouth and jaw anatomy with the exactitude of the GXCB-500. Determine precise tooth positions, bone structure, locations of relative anatomy, and vital structures using complete, 360-degree, three-dimensional scans that display vividly on your computer monitor.

In its Standard Scan mode of 8 cm in diameter by 8 cm in height, the GXCB-500 captures both arches in a single, ultra-speed scan. With this "molar-to-molar" view, images emerge as essential tools for implant planning and surgical planning, as well as endodontics. Cone Beam 3-D imaging generates anatomically correct assessments that support more predictable outcomes in a variety of surgical procedures and implant placements.

But the GXCB-500 doesn't stop here. A unique feature allows you to change from Standard to Extended Diameter Scan (EDS) mode and widen your field of view up to 14 cm in diameter by 8 cm in height. This provides the ability to capture the condyles, for improved TMJ diagnosis and treatment. This Extended Diameter Scan also shares valuable, clear-cut information for airway analysis.