CBCT – Helping You Make a Confident Choice
How Can Our Patients See What We See?
As endodontic specialists, we’ve spent years navigating rigorous academic paths, defending our credentials, and earning the degrees that now hang proudly on our walls. However, if we’re unable to clearly communicate and educate our patients about their procedures and the advanced technology available to them, then we’re falling short of delivering care at the highest level.
This blog is an opportunity to pause and view treatment from the patient’s perspective. Our goal here is to explain how 3-D imaging plays a vital role in our practice and how it enhances the success and accuracy of endodontic care.
Many patients are unfamiliar with the term “CBCT,” and we often hear a range of questions like, “What exactly is it? Why is it necessary? Didn’t my dentist already take X-rays? I don’t want more exposure to radiation. Could this lead to cancer? Why are you scanning a different tooth than the one that hurts? I already had a panoramic scan—shouldn’t that be enough? Is this something I can afford? Can’t we just proceed without it?”
We understand where you're coming from—and your concerns are valid.
One of the most powerful benefits of CBCT in endodontics is its ability to provide detailed 3D images that traditional intraoral and panoramic X-rays simply can’t offer. CBCT technology compiles data to create detailed images in three intersecting planes: axial, sagittal, and coronal—offering a comprehensive view that’s essential for precise diagnosis and treatment planning.
Cone Beam Computed volumetric Tomography
Cone Beam Volumetric Computed Tomography (CBCT) is an advanced imaging system that delivers detailed, 3D radiographic views of the targeted area using a small field-of-view and high-resolution technology.
The Kodak 9000 3D system is engineered to support enhanced patient outcomes by offering highly precise treatment planning with a lower radiation dose.
Comfort during imaging is a major focus. The Kodak 9000 3D’s open, face-to-face configuration improves patient positioning, promotes eye contact to reduce anxiety, and mirrors the process of panoramic imaging—something many patients have experienced. The unit is designed to accommodate various body types and is fully accessible for patients using wheelchairs.
CBCT in Endodontics
In general, the use of CBCT in endodontics should be limited to the assessment and treatment of complex endodontic conditions such as:
-
Identification of root canal system anomalies and determination of root curvature.
-
Diagnosis of dental periapical pathosis in patients who present with contradictory or nonspecific clinical signs and symptoms, who have poorly localized symptoms associated with an untreated or previously endodontically treated tooth with no evidence of pathosis identified with conventional imaging.
-
Assessment of treatment complications, such as overextended root canal obturation material, separated instruments, calcified canal identification and localization of perforations.
-
Management of trauma, especially root fractures.
-
Localization of external from internal root resorption or invasive cervical resorption
-
Presurgical case planning to determine the exact location of root apices.
-
How does it work?
CBCT is accomplished by using a rotating gantry to which an x-ray source and detector are fixed. A divergent cone-shaped source of ionizing radiation is directed through the middle of the area of interest onto an area x-ray detector on the opposite side of the patient. During the exposure sequence, hundreds of planar projection images are acquired of the field of view (FOV) in an arc of at least 180°. In this single rotation, CBCT provides precise, immediate and accurate 3-D radiographic images. CBCT utilizes a cone shaped x-ray beam and an area detector that acquires a full volume of images in a single rotation, with no need for patient movement.
How much radiation?
Radiation is a natural part of our environment. It comes from a variety of sources, including cosmic rays from outer space, terrestrial radiation from the earth, and even small amounts generated within our own bodies. Roughly half of the average American’s yearly radiation exposure originates from these natural sources. On average, this natural exposure amounts to around 3.1 millisieverts (mSv), or 3,000 microsieverts (μSv), per year.
The concept of ALARA—which stands for As Low As Reasonably Achievable—is a foundational guideline in diagnostic radiology. This principle encourages clinicians to minimize radiation exposure by opting for CBCT (cone-beam computed tomography) only when lower-dose imaging, such as standard dental X-rays, will not provide sufficient diagnostic information. CBCT and traditional CT scans generate vast data sets comprised of millions of tiny 3D units called voxels. Voxels are the 3D equivalent of pixels and represent specific values on a grid within three-dimensional space. Because CBCT voxels are isotropic (uniform in all dimensions), they allow for precise, distortion-free measurements in any direction.
To compare radiation risks across different imaging methods, exposure levels are translated into effective dose, measured in Sieverts (Sv). Since the Sievert is a relatively large unit, doses in dental and maxillofacial imaging are more commonly expressed in microSieverts (μSv).
Digital periapical X-rays typically result in effective doses ranging from 5.5 to 22.0 μSv. For context, this is considerably lower than the average yearly background radiation dose of 3,000 μSv (or 3.0 mSv).
The amount of radiation from a single 3D CBCT scan is generally comparable to that of one to five standard digital periapical radiographs. Refer to the chart below to view dose comparisons for CBCT scans taken in either the anterior or posterior regions.
Conventional intraoral radiography provides clinicians with high-resolution imaging that continues to be the front-line method for dental imaging. However, it is clear that there are many situations where the 3-D images produced by the CBCT cannot be disputed. It is a valuable imaging modality, producing minimal radiation exposure to the patient and providing maximal information to the clinician.
Thanks for visiting Ocean MicroEndodontics.
Special thanks to the following resources:
1. AAE for Figures 1-3 utilized from their Colleagues for Excellence Summer 2011: Cone Beam-Computed Tomography in Endodontics
2. Dr. Christine Peters & Dr. Ove Peters: The Nuts and Bolts of Computed Tomography 2011
3. Ludlow JB et al, White SC, Pharoah MJ. for the table on ionizing radiation dosages