Is it Time to Say Goodbye to our DSLR Cameras?

By Dr. Anthony M. Puntillo, DDS, MSD

When I first graduated from my orthodontic residency, now more than 23 years ago, a standard set of initial records included plaster models, facial and intraoral photographs taken with film, developed, then trimmed and placed into mounts and panoramic and lateral cephalometric radiographs taken with film and developed in darkrooms. The digitization of our society has made the process of gathering and storing this important diagnostic information much more efficient for most orthodontists. In fact, more than four years ago (November 2012) I wrote a Tech Blog article on digital retainers and the impressionless orthodontic practice. Since then the use of intraoral scanners and 3D printing in our profession has grown exponentially. It is now not hard to imagine a day in the near future when impressions will disappear completely from the practice of dentistry.  As I near the end of my 8 year term on the CTECH committee, I can’t help but wonder what is next.   Where else can we use technology to eliminate inefficient processes from our practices?

The most obvious next step for me is the elimination of intraoral photographs. All of those intraoral scanners, now used by most orthodontists, take multiple photographs of our patients’ teeth to create the 3D digital images. Several of these scanners can capture images in true, or close to true color. It can’t be long before we come to the realization that digital images taken with a good intraoral scanner are a better alternative to the standard set of 5-7 intraoral 2D photos we have been taking for decades. The 3D digital image is not only a better diagnostic record of the patient’s current dental state, it also is more versatile in that it can also be used to create and fabricate appliances (i.e. clear aligners, indirect bonding setups, retainers, etc.). If a good intraoral scan can consistently be completed in less than 10 minutes, aren’t we wasting our time and that of our patients’ taking 2D photos. I concede that we are all very accustomed to diagnosing our patients with these 2D photographic images. However, it was not that long ago when most thought that multiple radiographic exposures were necessary on the majority of our patients.   Now most of our patients are diagnosed with a single, quick radiograph taken on a CBCT machine and from that single exposure we derive a much higher level of diagnostic information.

To be honest, I am not yet ready to mothball our cameras. For starters, I still think that facial 2D photos are necessary. I know that there are 3D cameras available that will someday eliminate the need for our extraoral series of facial photos. However, for whatever reason (I believe primarily cost) these have not yet caught on. So for now we will still be taking a series of three 2D digital photos of our patients’ faces. Additionally, 2D intraoral pictures still play a significant role in our new patient consultations. We have not yet found the best way to display and share the captured 3D dental images (STL files) to educate our patients. I anticipate that this last hurdle will be overcome in 2017 and when that happens our DSLRs are going to see much less action and our IOSs are going to play an even larger role in our new patient process.

Radiation Exposure as Low as XX μSv…

by Juan Martin Palomo DDS, MSD
With the advent of Cone Beam Computed Tomography (CBCT), the amount of radiation received by the patient became an issue of heated discussions and controversies.  Perhaps one of the most asked questions would be “How much radiation would the patient receive for a CBCT scan with this or that scanner, assigning radiation exposure to a scanner brand?”
This created a lot of confusion.  The amount of radiation that patient receives during a scan has to do with the same physics’ principles as any other radiograph, which are mA, kVp, amount of time the beam is on, and area irradiated (confined by collimation).  Any CBCT scanner would give several different combinations of the above variables, and would be able to create CBCT volumes using a wide range of radiation exposure.  So the answer can never be a single number.  But this is sometimes misrepresented as a single number, almost as the marketing trick used by retailers when they use phrases such as, “as low as $XX”, or “starting at $XX”.
Usually the item one likes is not at that starting price, is it?  Some scanners do have advantages over others, by providing what’s referred to a “pulse mode”, which means the beam would turn itself on and off while taking all the images necessary, reducing the amount of radiation received.  But many times, the settings used (mA and kVp) will determine both image quality and radiation received, and unfortunately, at this time, there is no consensus on settings to be used for specific protocols.
In medicine, one cannot answer with a single number the question of how much radiation is received when having a CT scan, but there are protocols in place for specific imaging, such as CT of the brain for example.  The protocols determine the recommended mA and kVp to be used, and those can be used independently of the CT scanner brand, and will be different from a CT of a different part of the body.
We do have protocols for periapical radiographs, but not yet for CBCT’s.  Orthodontic CBCT’s would probably use lower settings than CBCT’s used for pathologic examinations or implant placement.  If we have protocols, perhaps all scanner brands would offer the same options as far as settings, and patients would receive the same amount of radiation for the same procedure, independently of the scanner brand used, or the office they decide to go.  Right now this is not the case, and even though radiation exposures can be considered low, they are different in different offices, when used for the same purpose.
The advances in technology, through better software filters and hardware changes such as “pulse” are helping to reduce the amount of radiation received by the patient, but there are still options that the operator must choose, and these can make a big difference.