A standard dental X-ray – the small film or sensor your dentist places in your mouth – produces a flat, two-dimensional image of a three-dimensional structure. For decades, this was all that was available, and skilled dentists learned to interpret these images expertly. But a 2D X-ray has inherent limitations that can directly impact the accuracy of a root canal diagnosis and the completeness of treatment.
Cone beam computed tomography (CBCT) produces a full 3D image of the tooth, root, surrounding bone, and nearby anatomy from a single short scan. It is one of the most significant advances in endodontic care over the past 20 years, and it is a standard part of every evaluation at St. Petersburg Endodontics.
What is CBCT imaging?
Cone beam CT (also called CBCT or 3D dental X-ray) is a type of computed tomography specifically designed for dental and maxillofacial imaging. Unlike medical CT scanners, which are large and deliver higher radiation doses, CBCT units are compact, chair-side machines that capture a full 3D data set of the oral structures in a matter of seconds with a radiation dose comparable to a standard dental X-ray series.
The resulting image can be rotated, sliced in any plane, and examined from any angle, giving Dr. Hedrick a complete picture of anatomy that simply cannot be obtained from flat X-rays.
What can CBCT reveal that standard X-rays cannot?
Extra canals that would otherwise be missed
This is arguably the single most impactful clinical benefit of CBCT in endodontics. Teeth, particularly upper molars and lower premolars, frequently have more canals than are visible on a 2D X-ray. The MB2 canal in upper first molars, for example, is present in the majority of patients but is missed in a significant percentage of cases treated without 3D imaging.
A missed canal cannot be disinfected or sealed. It remains a source of bacteria and is a primary reason root canals fail. One of our patient video testimonials documents exactly this: a patient whose tooth had been treated by another provider, only for Dr. Hedrick to discover additional canals using CBCT that explained the ongoing symptoms. Those canals were found and treated and the tooth was saved.
The true extent of bone infection
Periapical lesions, areas of bone destruction around an infected root tip, an be significantly underestimated on flat X-rays. CBCT reveals the true three-dimensional extent of the lesion, which informs treatment planning and helps Dr. Hedrick give you a more accurate prognosis.
Root fractures
Vertical root fractures are one of the most difficult diagnoses in dentistry; they are often invisible or ambiguous on standard X-rays, yet they are a definitive sign that a tooth cannot be saved with endodontic treatment and should be extracted rather than treated. CBCT dramatically improves the detection rate of root fractures, sparing patients from futile treatment.
Calcified canals
As we age, canals can narrow significantly due to secondary dentin deposition, making them increasingly difficult to negotiate. CBCT shows exactly where the calcification is, how extensive it is, and how to approach it instrumentally. This information changes the surgical approach and significantly reduces the risk of complications.
Anatomy of adjacent structures
CBCT shows the relationship of the tooth roots to the sinus cavity, the inferior alveolar nerve, and adjacent teeth, which is critical for surgical planning during apicoectomies and adds an important safety margin to any complex endodontic case.
CBCT and the surgical endodontic procedure
For apicoectomies, 3D imaging is not just helpful, it is essential. The precise location and angulation of the root tip, the topography of the bone overlying it, and the proximity to adjacent anatomy all directly determine how the surgery is planned and executed. Attempting microsurgery without a 3D roadmap is like navigating without a map.
Dr. Hedrick uses CBCT data to plan the exact size and location of the surgical access, the depth of root end resection, and the angle of the root end cavity preparation before the procedure begins. The result is a more predictable, less invasive surgery with a faster recovery.
How much radiation does CBCT produce?
Patient safety is a fair and important question. Dental CBCT delivers a radiation dose that is substantially lower than medical CT scans and is in a similar range to a full-mouth series of conventional dental X-rays. The scan takes only seconds and is performed selectively; we use CBCT when the clinical information it provides will meaningfully influence diagnosis or treatment, not as a routine procedure for every visit.
Frequently asked questions
Will my insurance cover the CBCT scan?
Coverage varies by plan. Many dental insurance plans cover CBCT when it is clinically indicated for endodontic diagnosis or surgical planning. Our team will check your benefits in advance.
Do I need to do anything special to prepare for the scan?
No preparation is needed. The scan takes only a few seconds and is entirely non-invasive. You simply sit or stand near the unit while the arm rotates around your head once.
Can I bring my existing X-rays to my appointment?
Absolutely, please do. Previous radiographs help Dr. Hedrick understand the history of your tooth and compare changes over time. In some cases, existing X-rays reduce the need for additional imaging.
Why doesn’t my regular dentist have this technology?
CBCT units are a significant equipment investment and require specific training to interpret the 3D data set accurately. They are more common in endodontic specialty practices, oral surgery offices, and larger dental groups than in general dentistry, though adoption is growing.
At St. Petersburg Endodontics, 3D imaging is a standard part of how we diagnose and plan every case — not an upgrade. If you’ve been told you need a root canal, retreatment, or endodontic surgery, contact us at (727) 521-2285 or online. Serving St. Petersburg, Clearwater, Largo, Pinellas Park, and all of Pinellas County.
Dr. Randall Hedrick | Board-Certified Endodontist, American Board of Endodontists | Certificate in Endodontics, University of Texas Health Science Center (1993) | 40+ years in practice