CBCT (cone beam computed tomography) can often be used to help diagnose and manage orthodontic conditions. In this post, our Calgary orthodontists discuss how we leverage this imaging technology, and its value.
What is CBCT?
Cone beam computed tomography (CBCT) is a specific type of X-ray machine that generates 3D images of dental structures, nerve paths, bone and soft tissues in the craniofacial region within a single scan.
This piece of equipment uses a cone-shaped beam and reciprocating solid-state flat panel detector that rotates around the patient 180 to 360 degrees, covering an area of interest, versus the slice-by-slice imaging we obtain from conventional CT.
In orthodontics, clear imaging is key to accurate diagnosis, growth evaluation and treatment planning, and CBCT can serve as an important source of data and allow us to visualize a patient's craniofacial complex in three dimensions instead of two.
How can CBCT be used in orthodontics?
Images obtained with CBCT can help orthodontists conduct precise treatment planning for children, teens, and adult patients with orthodontic conditions. This imaging technology has advanced enough to provide us with more reliable information than conventional radiography. Here are a few examples of how our orthodontists can use CBCT at myORTHODONTIST to diagnose and treat a range of conditions.
Diagnosis
- Impacted or transposed teeth (and accurately assess any resorption of roots in surrounding teeth)
- Craniofacial anomalies such as cleft palates
- Abnormalities in the temporomandibular joint (TMJ)
- Evaluation of airways when identifying whether a patient has obstructive sleep apnea
Treatment Planning
- Accurately estimating how much space is needed for impacted or unerupted teeth
- Planning orthognathic surgery to treat severe skeletal conditions
- Assessing the need for maxillary expansion
- Planning for fabrication of custom orthodontic appliances
- Planning for placement of temporary anchorage devices (TADs)
- Used in conjunction with CAD/CAM technology for the construction of custom orthodontic appliances
Treatment Progress
- Orthognathic surgery superimposition
- Assessment of dentofacial orthopedics
- In patients with cleft palates - outcomes of alveolar bone grafts
Risk Assessment
- Assessing root resorption related to orthodontics
- TMD post-treatment
- Assessing orthodontic-related paraesthesia
Of course, while CBCT can assist in a wide range of diagnostic and treatment management procedures, evaluation is still needed on whether this or other imaging technology would be best for the job. In addition, while advances in technology have lowered the dose of radiation per imaging session, only areas of interest should be examined to further minimize the radiation dose.
Why use CBCT technology to assess patients?
Now that we understand how CBCT technology can be used, we'll answer the question of why we'd choose to leverage it. Some of those reasons include:
Obtaining Accurate Images with a Rapid Scan Time
With CBCT imaging technology, we can quickly and accurately capture real-size, distortion-free 3D images using a non-invasive technique, typically within a range of 5 to 40 seconds. The images are also free of overlapping, magnification and distortion of structures in the oral cavity.
Limited X-ray Beam
The X-ray dose is significantly less than with CT - between 6 to 15 times.
Fewer Head Movements Necessary
Fine adjustment of a patient's head position is not essential for CBCT, which can potentially make this imaging method less time consuming than others.
What about radiation?
Using CBCT for orthodontic assessment, diagnostics and treatment planning and management can help increase the chances of positive outcomes for certain conditions. While radiation doses from CBCT exams are typically lower than other CT technologies, CBCT usually delivers more radiation than conventional dental X-ray exams.
For younger patients, radiation exposure is more of a concern due to their sensitivity to radiation. therefore, we only use CBCT when necessary for orthodontic diagnosis or treatment, and will always weigh the benefits of using X-ray imaging vs. this method.
To minimize any risk to health, we'll review risks and benefits of this procedure with patients, and discuss whether using CBCT is necessary along with any alternatives that use less or no ionizing radiation.