Panoramic (PAN) and three-dimensional radiographs such as cone beam computed tomography (CBCT) provides invaluable information for clinicians for various reasons. These types of imaging can be utilized daily in many types of dental practices, including general dentistry, endodontics, periodontics, oral surgery, dental imaging centers, and orthodontics.
These images provide not only an enormous amount of dental information but also a patient’s overall health. They have the potential to alert the dental professional to a potentially life-threatening condition: carotid artery disease.
Carotid Artery Disease
Carotid artery disease (CAD) occurs when the arteries that supply blood and oxygen to the brain become clogged and/or narrowed due to plaque buildup within the artery.1
If left untreated, it can lead to debilitating consequences and, in some cases, death by way of a stroke. Stroke is the most common cause for permanent disability in the United States.1
It is important to note that this complication can occur in any artery of the body, but this article will focus on the carotid due to its clinical significance for dental professionals.
Signs, Symptoms, and Complications of Carotid Artery Disease
In the early stages, carotid artery disease may not display any obvious signs or symptoms. As the disease progresses and becomes more severe, it can lead to either a transient ischemic attack (TIA) or a stroke. Both of these complications cause a temporary loss of blood flow to the brain. The signs and symptoms of both a TIA and stroke are identical, but a TIA usually lasts only for a few minutes and up to an hour at most. The person will be fully recovered from the TIA after 24 hours.2,3
In contrast, a stroke lasts longer, and the complications can be long-lasting, and in some cases, permanent.1-3
The symptoms for both TIA and stroke can include sudden weakness of limb(s) the face (usually affecting only one side of the body), speech difficulty, vision disturbances, confusion, and a sudden, severe headache.1-3
Any of the above symptoms are cause for concern and require immediate emergency medical attention.
Risk Factors and Treatment
There are many risk factors for carotid artery disease, which can include diabetes, high blood pressure, high cholesterol and triglycerides, obesity, sleep apnea, sedentary lifestyle, family history and genetics, and a high-fat diet.1-3
Treatment of carotid artery disease depends upon the severity of the disease. Evaluation for potential carotid artery disease can include a combination of:
- A physical exam where the treating physician evaluates the carotid artery for a “bruit,” which is commonly described as a “whooshing” sound and can indicate a blood flow issue
- Ultrasound, CT, or MRI scan
- A more detailed image, called an angiography, where a contrast dye is used in combination with either a CT or MRI to allow for a detailed image of the neck and brain.1
Many times, if the artery is narrowed by less than 50%, it can be treated with medications and life changes. These adjustments may include smoking cessation, implementing an exercise regime, limiting sodium intake and high-fat foods, and medications that lower blood pressure and cholesterol, as well as antiplatelets.1,3
If the artery is narrowed by greater than 50%, one of two types of surgical interventions may be required in order to prevent a TIA or stroke. The most frequently used of the two interventions is a procedure called carotid endarterectomy. During this procedure, a surgeon makes an incision in the neck and cleans out and removes any plaque buildups that are clogging the artery.1,3
If a patient is unable to have a carotid endarterectomy, another surgical intervention called carotid angioplasty and stenting procedure may be performed. During this surgery, a catheter is placed inside a blood vessel in the groin and is threaded up to the carotid artery. A balloon is then placed inside the artery and used to widen it so that a mesh stent can be placed inside the artery. The stent keeps the artery open and allows for adequate blood flow to the brain.1,3
The treating physician will determine the percentage of narrowing and the severity of the disease as well as the best course of treatment.
Panoramic Radiograph versus CBCT
A PAN radiograph is a two-dimensional image, and a CBCT is a three-dimensional image. A PAN used to be used more frequently than three-dimensional imaging in dentistry, but CBCT has continued to gain popularity over recent years. Part of this is due to the fact that there are limitations to two-dimensional radiographs. For example, images may be enlarged, distorted, and superimposed.4 The accuracy in a CBCT image is much higher compared to a PAN image because it utilizes the more precise three-dimensional technology.4
While CBCT provides more valuable information, it does expose a patient to a higher level of radiation than a PAN, so the clinician should always weigh the risk versus benefit for the patient and limit a patient’s radiation exposure.
Clinicians should adhere to the ALARA principle (“As low as reasonably achievable”) when determining which dental images they will utilize.5,6
Identifying Potential Carotid Artery Disease on Dental Images
On a PAN, carotid artery calcification (CAC) can appear as a radiopaque lesion that is either rounded or nodular in shape (see Images 1 and 2). CACs most often present themselves between the C3 and C4 vertebrae. They can be localized to one side or appear bilaterally.7 One article stated, “Panoramic radiographs may help us to detect CACs in patients with or without other associated risk factors.”7 This means that dental hygienists may be the first ones to discover these in their patients.
While CACs can be identified on a panoramic image, they are even more identifiable on a CBCT due to their high level of detail. In regard to the CBCT, one article stated, “Small calcifications are easier to be identified on a CBCT scan than PAN or intraoral radiographs.”8
On these images, CACs most commonly appear in the cervical tissue. From the axial view, they can be described as “single or multiple “rice grains” with a homogeneous opacity and a linear or curvilinear shape.” They appear “approximately 0-10 mm anterolaterally to the anterior tubercle of the transverse process; lateral or more often lateroposterior to the greater cornu of the hyoid bone; and always posterolateral to the pharyngeal airway space. In coronal projections, CAC depiction appears lateral to the anterior tubercle of the cervical vertebrae. On the sagittal sections, CACs are identified medial and inferior to the angle of the mandible, lateral and mostly anterior to the cervical tubercle with their vertical position varying from C3 to C5.”9 For an example of what a carotid artery blockage looks like on a CBCT click here (see figures 1 and 2).9
Any of these dental images has the potential to be life-saving screenings for our patients.
Role of the Dental Hygienist
As dental hygienists, we are experts on not only oral health but the connection between oral and systemic health. We understand that many systemic diseases and disorders have a bi-directional relationship with oral health. All of our patient’s health histories are important, but when considering our patient’s risk for carotid artery disease, those who have a history of carotid artery disease, hypertension, patients taking cholesterol medications, and diabetes should alert us to be on the lookout for potential CACs on their dental images.
Hygienists are known for their keen eye and attention to detail, both of which can be truly life-saving. Identifying potential carotid artery disease on a patient’s radiographs is just one example of this.
The entirety of a PAN or a 3D image should be carefully evaluated; this evaluation is not limited to the teeth only. Looking at the entire “picture” can alert the clinician to potential dangers.
If there is any lesion found on a PAN or CBCT, the patient should be referred to their primary care provider or other pertinent health-care physicians for an evaluation. It would be helpful to send a copy of the image to the provider so that they know exactly what the patient is being referred for.
Listen to the Today’s RDH Dental Hygiene Podcast Below:
- Carotid Artery Disease. (2018, October 4). Mayo Clinic. Retrieved from https://www.mayoclinic.org/diseases-conditions/carotid-artery-disease/symptoms-causes/syc-20360519
- Transient Ischemic Attack. (2020, March 7). Mayo Clinic. Retrieved from https://www.mayoclinic.org/diseases-conditions/transient-ischemic-attack/symptoms-causes/syc-20355679
- Carotid Artery Disease. (n.d.). Johns Hopkins Medicine. Retrieved from https://www.hopkinsmedicine.org/health/conditions-and-diseases/carotid-artery-disease
- Acar, B., Kamburoglu, K. Use of cone beam computed tomography in periodontology. World J Radiol. 2014; 6(5): 139–147. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4037540/
- Dental Cone-beam Computed Tomography. (2020, September 28). U.S. Food & Drug Administration. Retrieved from https://www.fda.gov/radiation-emitting-products/medical-x-ray-imaging/dental-cone-beam-computed-tomography
- Dental radiographs Benefits and safety. JADA. 2011; 142(9). Retrieved from https://www.ada.org/~/media/ADA/Publications/Files/for_the_dental_patient_sept_2011.pdf?la=en
- Bahemmat, N., Evazzadeh, M.E., Hadian, H., Moshfeghi, M., Taheri, J.B. Relationship Between Carotid Artery Calcification Detected in Dental Panoramic Images and Hypertension and Myocardial Infarction. Iran J Radiol. 2014; 11(3). Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4341178/
- Kiran, M., Kumar, M., Shanavas, M., Sidappa, A. Cone Beam Computed Tomography – Know its Secrets. Journal of International Oral Health. 2015; 7(2): 64-68. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4377156/pdf/JIOH-7-64.pdf
- Damaskos, S., Aartman, I.H.A., Tsiklakis, K., van der Stelt, P., Berkhout, W.E.R. Association between Extra- and Intracranial Calcifications of the Internal Carotid Artery: A CBCT Imaging Study. Dentomaxillofac Radiol. 2015; 44(5). Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4628503/
- Kalid, A., Lucinda, J.L. (2017, August 23). Identifying Carotid Artery Atheromas on Pantomographs. The Journal of Multidisciplinary Care Decisions in Dentistry. Retrieved from https://decisionsindentistry.com/article/identifying-carotid-artery-atheromas-pantomographs/