Cone-beam CT scanner dangerous and/or justified?

This forum made possible through the generous support of SDN members, donors, and sponsors. Thank you.

newpredent

Full Member
10+ Year Member
Joined
Aug 21, 2010
Messages
36
Reaction score
0
There was an article in the New York Times on November 22 about the possible risks on cone-beam scanners.

http://www.nytimes.com/2010/11/23/us/23scan.html?_r=1&hp

The article cites several instances of conflict of interest between dentists and cone-beam manufactures. It also states that the amount of radiation being emitted is not well known.

Any thoughts on the use of this technology? Also, the article points out that several dentists still use D speed radiographic film. How common is this?

Members don't see this ad.
 
cone beam gives good 3d imagery. It makes some things in dentistry more accurate. However, there are other technologies out there that have been used to do the same things. The amount of radiation emitted can be measured and controlled. This is a red herring.

Some people still use film. It is slow compared to digital but has predictability and well established limitations. Digital can be deceptively simple to use, can have software that can be confusing, and low per image cost. Depending on the system and the technique, image quality is not consistent for all digital images.
 
CBCT is going to be a bit of a hot/controversial topic in dentistry for the next few years to say the least.

Can CBCT produce images, especially for oral surgery, implant placement and even endodontics that essentially provides a level of detail/information that traditional films (either classical intra-oral or digital) can't even come close to? Yes. How nice is it for the oral surgeon to know EXACTLY (in all 3 dimensions)where that inferior alveolar nerve is with respect to the apices of a lower third molar before beginning the treatment?? How nice is it for the doc placing that implant to know the exact location/thickness of dense cortical bone prior to opening up an implant site?? How nice is it for an endodonist to know that the MB root of #3 curves first buccally before making the distal curve that traditonal imaging techniques show?? CBCT undoubtedly has the ability to provide a clinician with a much greater degree of detail BEFORE the procedure begins which can translate into a better potential outcome and often an easier course of treatment for both the patient and doc (from the doc perspective it's usually nicer to know that you're getting into a tough case BEFORE you start, as often you can better plan for it both time wise, and often mentally too)

The issues will be, for a dentist considering purchasing one, #1 is the cost justified?? (remember today their running somewheer between 100k upto about 175k) and will the doc get a wide field view or a narrow field view??? Radiation wise, well it's not like anyone is advicating using a CBCT for regular screening diagnostic imaging, so IMHO that's not an issue in this case. Bottomline, if a medical specialist says you need a CT to help diagnose a medical problem, most folks don't think twice about getting the CT done. I forsee dental applications of CBCT being the same. Isolated, diagnostic images
 
Members don't see this ad :)
CBCT is overused. I am aware that some orthodontic residency programs get a full head and neck CBCT on every patient. I would argue orthodontic outcomes are no better now than they were 10 years ago when a lateral and PA ceph were the primary diagnostic images. 3D evaluation can be very useful for planning orthognathic/craniofacial surgery in patients with significant facial asymmetry. Tomographic evaluation is vital for much of dental implant treatment planning. Regarding the IAN, I haven't seen any data that shows CBCT decreases the incidence of permanent paresthesia. In my 3.5 years of residency so far, I've done over 1,000 third molar sets and haven't gotten a CBCT for pre-extraction evaluation of an IAN, despite it being readily available. No paresthesias so far (knock on wood). The only time I can forsee it being a critical issue in third molars is if the nerve is surrounded by the roots, which is exceedingly rare.

One factor in whether or not to use CBCT in OMS is potential litigation. CBCT may become more widely used in pre-op planning for OMS simply because more and more surgeons are using it, making it the standard of care. All in all, it's not the end of the world. 4-5 panos per CBCT was the dose equivalent in the NYT article. That's a heck of a lot better than a head CT. And a million times better than a myocardial perfusion scan!
 
Last edited:
CBCT is overused. I am aware that some orthodontic residency programs get a full head and neck CBCT on every patient. I would argue orthodontic outcomes are no better now than they were 10 years ago when a lateral and PA ceph were the primary diagnostic images. 3D evaluation can be very useful for planning orthognathic/craniofacial surgery in patients with significant facial asymmetry. Tomographic evaluation is vital for much of dental implant treatment planning. Regarding the IAN, I haven't seen any data that shows CBCT decreases the incidence of permanent paresthesia. In my 3.5 years of residency so far, I've done over 1,000 third molar sets and haven't gotten a CBCT for pre-extraction evaluation of an IAN, despite it being readily available. No paresthesias so far (knock on wood). The only time I can forsee it being a critical issue in third molars is if the nerve is surrounded by the roots, which is exceedingly rare.

One factor in whether or not to use CBCT in OMS is potential litigation. CBCT may become more widely used in pre-op planning for OMS simply because more and more surgeons are using it, making it the standard of care. All in all, it's not the end of the world. 4-5 panos per CBCT was the dose equivalent in the NYT article. That's a heck of a lot better than a head CT. And a million times better than a myocardial perfusion scan!

It will help in Oral Diagnosis/Oral Path/Oral Medicine and OMFS for lesions, atypical pain, etc.

As it is now we use a CT (which can give a 3D image) on those in-patients who can not sit for a panorex or able to take PAs,,, we have 3 views - the classic from skull down to neck; Laterial (excellent views of molars/premolars) and frontal (excellent views of anterior teeth)
- and the patient can be asleep for entire study.
 
Top