CBCT Imaging for your Practice: Is Now the Time?

By Dr. Kenneth R  Webb

As I walked the exhibit floor at the AAO Annual Session in San Diego this past April, I stopped and talked to several of the company reps displaying the latest generation of CBCT scanners. Competition is good – what struck me is how far this technology has come in such a short period of time. Effective dose, image quality, and versatility are three areas where the advances are most impressive. I have witnessed these advancements first hand in my practice where we have been using CBCT since 2012 and recently upgraded a satellite office from a 2D digital Pan / Ceph to an “Ultra Low Dose” current generation CBCT scanner. I’d like to share some of my thoughts about the 2D to 3D transition.

Effective Dose
I encourage anyone interested in CBCT technology to search for studies authored by Dr. John Ludlow and his team. Dosimetry data and image quality for many CBCT scanners (both older and current generations) have been researched in great detail. Comparative data for 2D dental radiographic imaging (both intra and extra oral) is also available. By replacing our 2D Digital Pan / Ceph with a current generation CBCT scanner we have reduced the effective dose of our diagnostic records imaging by approximately 60%. (Ludlow JB, Walker C. AJO-DO, 2013;144 (6): 802-817) This is accomplished with one, approximately 5 second, ultra-low dose CBCT scan compared to the two longer duration exposures (pan then ceph) required with 2D imaging. Certainly a win-win for our patients.

Versatility
What else can we use the 3D data for? Digital models: used to assess the inter-arch and intra-arch relationship as well as aiding the determination of arch length and arch width requirements and assessing arch symmetry. Modelling labs can produce articulated 3D study models from the CBCT data (DICOM) files.

STL files of the patient’s dentition and occlusion can be uploaded into whatever software you may be using in your office for 3D model storage and viewing. Additionally, these models can be used (with appropriate software) to produce treatment simulations by “moving” individual teeth or the arches as a whole. Imagine completing your diagnostic records with Intra / Extra Oral photos and one 5-second CBCT scan!

Viewing the Diagnostic Data
The software that comes with a CBCT scanner can easily produce the customary 2D diagnostic images that we are used to evaluating (panoramic, lateral and A-P ceph). In addition – you see everything! The data can be viewed in sagittal, axial or coronal sections (slices) or as a 3D “volume rendering” which can be rotated and sliced (“clipped”) at will. So why is this additional information gained from CBCT imaging important?

Pathology
You will see pathology in the 3D data that isn’t visible with standard 2D imaging. When pathology is visible in 2D, the 3D data can more accurately ascertain location, extent, and character of the area of concern. This is beneficial to our patients.

Developmental Anomalies
One of my first revelations when we began imaging in 3D was the prevalence and extent of “individual anatomic variation”. But how much is too much? We have made referrals to medical specialists for significant developmental anomalies in the cervical spine, nasal cavity and paranasal sinuses. Patients / parents are appreciative of the thoroughness of our diagnostic process that includes 3D imaging.

Asymmetries
They get their own paragraph! Your patient smiles at you and you notice a vertical asymmetry and occlusal plane “smile” cant. Is it caused by hemimandibular hyperplasia, condylar hyperplasia, a unilateral expansive lesion in the maxilla, a growth response to unilateral progressive condylar resorption (to name a few) or a growth response to a foreign object lodged in the nasal cavity? I’ve seen them all. Similar clinical presentations – different treatment plans.

TMJ
Condylar position in centric occlusion, condylar size and shape, glenoid fossa morphology, condylar osseous morphology, joint space, findings suggestive of degenerative joint disease – both active and stable. It is hard to argue that these are not important considerations in our diagnostic process.

Airway
The value of volumetric and cross-sectional analysis of the naso – pharyngeal airway and its relationship to orthodontic diagnosis and treatment planning has, and continues to be, studied in great detail. Is the growth and development of a patient who presents with narrow arches, an anterior open bite or anterior crossbite, tongue thrust and a strong mouth breathing pattern secondary to adenoid / tonsillar hyperplasia, a deviated nasal septum, environmental allergies or restrictive airway dimensions in general? Should your imaging modality include an assessment of these areas?

And there is more…
Orthognathic surgical treatment planning, TAD placement guidance, precise localization of ectopic and supernumary teeth, and assessment of treatment progress – including evaluation of root torque. All are possible or enhanced with 3D imaging. And by managing scan parameters (field of view, scan time and voxel size) at an effective dose equal to or less than 2D imaging modalities.

So, if you haven’t brought this technology into your practice – is now the time?

At the 2017 AAO Winter Conference in Ft. Lauderdale, Mr. Chris Bentson reported on a survey of recent (2016) U.S. Orthodontic Residency graduates: 88% responded that they had used CBCT imaging for diagnosis and treatment planning during their residencies including 21% that used it on all patients.

For the 2013 graduates, the responses were 76% and 9% for the same questions.

Based on these statistics, are we that far away from 3D imaging being included in the “standard of care” discussion? Embracing new technology is not easy but the value added for the practitioner and our patients is significant. The orthodontic educators who expertly taught my generation faced a similar situation during their careers with a then relatively new technology: panoramic radiographic imaging. My generation faced the challenges of transitioning from analog imaging (film) to digital.

Change is not easy. The transition from 2D to 3D imaging in your practice will require a financial and educational commitment. The whole staff will be a part of this paradigm shift. A positive – 3D imaging will be a differentiator for your practice. If you are seeking an associate, partner or complete transition, 3D imaging will make your practice more attractive to the next generation of orthodontists.

3D imaging will benefit you and your patients. Is now the time?

2017 Winter Conference – Technology: Balancing Profit, Lifestyle & Patient Care

By Dr. Doug Depew

The 2017 AAO Winter Conference is quickly approaching. Our theme of this year’s meeting Technology: Balancing Profit, Lifestyle and Patient Care.  It promises to be a meeting filled with information for both newer and established practices to help make those tough decisions on what technology is important to use in our practices and when we may wish to invest in it.

The meeting will begin with keynote speaker Jack Shaw.   Mr. Shaw is a world- renowned technology futurist who will be discussing how cutting edge and disrupting technologies will change the way we do business and run our practices in the coming years.

IT guru Steve McEvoy will be answering some of those pesky questions we all have about computer hardware, effective and cost-efficient data backup, and security.   In the ever changing world of computers, what you hear at this meeting will certainly be different than what Mr. McEvoy would have talked about even a couple of years ago.

On Friday afternoon we’ll have a lively discussion by Drs. Greg Jorgensen and Neil Kravitz regarding building our practices through social media, websites, and Internet marketing. Their success in these areas has been paramount in growing their thriving practices.

Saturday morning will begin with Dr. Aaron Molen sharing his experience and thoughts on bringing emerging technology into our practices to help create more efficient and more comfortable patient care.

We’re excited to have Drs. Ed Lin and Christian Groth discussing how to integrate some of the latest technology hardware into our orthodontic practices. This includes workflows for using CBCT, Scanners and 3D Printing.

The conference will conclude with Chris Bentson and Charles Loretto with a discussion on how technology can affect the value and profitability in our practices. This should help answer the question about at what stage of practice a doctor might consider investing in advanced technology.

The location for the meeting is at the gorgeous Marriott Harbor Beach Resort and Spa in Ft. Lauderdale, Florida. The dates are February 10-11, 2017. The schedule is organized in a way to allow some time for afternoon recreation.

There will be plenty of time allotted for attendees to ask questions of the speakers to be sure all bases are covered.   To learn more and to register, visit https://www.aaoinfo.org/meetings/2017-winter-conference-technology-balancing-profit-lifestyle-patient-care

When Less is More, Regarding Radiation

J-Martin-Palomo-Headshotby Juan Martin Palomo DDS, MSD

We all know Cone Beam Computed Tomography (CBCT) by now. It allows a non-invasive, usually less than 10-second capture of the craniofacial anatomy, which is able to create all possible traditional 2D radiographs, giving far more diagnostic information. Probably the main mentioned reason of why it has not replaced the traditional panoramic and cephalometric radiographs in clinical orthodontics, is radiation. Depending on the settings used, it could expose the patient to more radiation than that of a ceph and pano. The radiation would still be considered low, according to the American College of Radiologists, and is less than the additional annual cosmic radiation that somebody living in high altitudes, such as Colorado, receives, but nevertheless, more than a ceph and pano. But this is no longer the case, for a while.

Most major CBCT manufacturers have now a low-dose scanner in the market, which allows the 3D image to be captured, with less radiation than a panoramic radiograph. It givless is more Palomoes a complete 3D image, where a pano, ceph, and complete 3D view can be used, for less radiation than that of a distorted pano. How is this possible? The answer is “capturing technology”.

When a low dose 3D image is captured, the scanner does not go all 360 degrees around the patient’s head. Sometimes it is just 180 degrees. The 3D image is basically a combination of several static images (radiographs) taken while the scanner rotates around the patient’s head. In a low dose option, the number of images captured are less than 200, as opposed to the usual 300-600. When a panoramic radiograph is being taken, the x-ray beam is “on” the whole time, beeping, while going around the patient’s head. In a low dose CBCT scanning, pulse technology is used, so the x-ray beam is only “on” for a fraction of a second while taking a quick image, turning itself “on” and “off” automatically, resulting in a total radiation exposure of about 2 seconds.

All this in combination with low radiation settings, results in total effective radiation to the patient in the teens or low twenties, compared to high twenties for a pano. And in this numbers game that is effective radiation, the suggested safety threshold is 30 microsieverts. Anything below 30 microsieverts can be considered low, and fair game.

Now for the very necessary disclaimers. This does not mean that because we can get to less than 30 microsieverts we should scan everybody. Zero is still less than 30. So if a radiograph that can answer the question clinically posed has already been taken, retrieve it and do not take an additional one. If no radiograph is necessary, don’t take one just because you can. But if a radiograph is needed, and a low dose CBCT is an option, I would have a hard time justifying a ceph and pano, as opposed to a low dose CBCT. And to take a pano or ceph before taking a low dose CBCT would also be unnecessary additional radiation to the patient.

The low dose CBCT alone has more than sufficient image quality for what we need in orthodontics. I have seen images from several manufacturers, and this is clearly a situation where less radiation to the patient is also more information to the doctor. What better win-win that this can we ask?

The Digital Generations

By Anthony M. Puntillo DDS, MSD

Dr.-Puntillo-PictureThe majority of the U.S. Workforce today is comprised of three generations:  Boomers (1946-64), Xers (1965-80) and Millennials (1981-99), each generation with its own unique set of characteristics.  The American Association of Orthodontists (AAO) now reports that more than 51% of its membership is composed of Gen Xers and Millennials.  By virtue of their birth timing Xers and Millennials, including myself (1966), were the first generations to grow up with computers in their homes.  Although Gen Xers differ from Millennials in many ways, technology is now ingrained into nearly every part of both generations’ lives.  For those Xers and Millenials that also happen to be orthodontists, this attachment to technology includes not only their personal lives, but also their orthodontic practices.

Over the last few years, my blog posts have centered on the discussion of a “Digital Orthodontic Practice.”  A digital practice must include not only the management and record keeping aspects (paperless) of our offices, but also clinical diagnosis and tooth alignment functions.  In this post, I want to highlight the current opportunities for moving digital in the clinical portion of your practice.

Diagnosis:

The clinical care for most orthodontic patients begins with a diagnosis and a treatment plan.  Given that Kodak is now only a shell of the company that it once was, I think it is safe to say most orthodontic practices are now taking digital photographs, instead of film, as part of their diagnostic records.  The recent 2014 JCO study of Orthodontic Diagnosis and Treatment Procedures1 found that more than 91% of the respondents used digital radiography, 69% used CBCT either routinely or occasionally, 41% used digital models and 28% used intraoral digital scanners.  Additionally,  the American Board of Orthodontics (ABO) recently announced that all initial models for their exam must be submitted in a digital format.  While the JCO survey included a relatively low number of respondents (n=135), I believe the findings are indicative of the Electronic Health Record (EHR) movement in all of the health care profession.  This movement, aided by government mandates and subsidies, has now breached the threshold level.  The train has left the station.  If you and your practice intend to stay relevant over the next decade, you absolutely need to be utilizing digital diagnostic records.

Tooth Alignment:

As our profession transitions to a digital diagnostic record norm, some are looking to move beyond diagnosis to digitally construct tooth aligning appliances.  In 1999, Align Technology opened the door to digital orthodontic tooth alignment with the introduction of the Invisalign system.  The system at that time relied upon traditional dental impressions, but today intraoral scanners and 3D printing have allowed for the elimination of the impression procedure.  Whether it be Align, or any other current Clear Aligner option, a digital model (.STL) of a patient’s dentition can be captured with a scanner, the teeth can be aligned using computer software, and treatment appliances (clear aligners) can be fabricated by machines based off of the digital “plan”.  Furthermore, this process can now also be utilized for patients using traditional bonded brackets.  Custom brackets along with custom bracket placement jigs and custom wires digitally planned and robotically bent are possible.  In large part because of costs and the learning curve, the digitization of clinical orthodontic procedures has not yet been completely accepted.   However, as the techniques become more refined, we should expect the cost to include them into our practices to decrease and implementation by the tech savvy Xers and Millennials to accelerate.  If you are an Xer or a Millennial, and have not already incorporated digital tooth alignment into your practice, you should be planning to do so in the near future.  If you are a Boomer, and potentially less comfortable with technology, you need to consider if you can afford to ignore this change.

Creating an esthetically pleasing and stable smile, can be a bit like designing and constructing a building.  In a recent conversation with a Boomer architect friend of mine he described the digital changes his profession has undergone.  My friend reported that my office, built in the year 2000, was one of the last buildings he drew by hand.  All of his projects now are digitally designed using 3D CAD technology, allowing him to plan and visualize the end construction result more effectively.  The transition in the architectural profession took time and learning.  Change is never easy.  However, as my friend now approaches the end of his career, he finds the “old” way inefficient and less accurate.   Whatever generation you were been born into, I encourage you to embrace the digital change our profession is in the midst of.  I am certain a digital orthodontics will ultimately benefit you and your patients.

1Keim Et.Al. 2014 JCO Study of Orthodontic Diagnosis and Treatment Procedures, Part 1: Results and Trends Journal of Clinical Orthodontics 2014; 48:10 pages 607-630.

Virtual Setups Using Intra Oral Scanners for Same Day Consultation

IOScan_exampleBy John White DDS, MSD, ABO

Having been in orthodontic practice for 35 years, I’ve seen a lot of changes in all aspects of orthodontic care.  Most changes have been totally under our control and are merely choices. Whether you choose to use self-ligating appliances or not impacts your mechanics but not really your ability to produce an excellent result. Most cases do not require a CBCT to adequately diagnosis or treatment plan to achieve that same excellent result. Robotic orthodontics, also known as pre-bent appliances, have benefits and drawbacks, but once again are unnecessary for creating that “perfect smile”. Most of us have never done more than dabble in lingual appliances; without any loss to our practice. And while clear aligner therapy has probably the greatest (potential) impact on the traditional delivery of orthodontic care, there are plenty of very successful orthodontic practices that presently don’t use it at all or only on a limited basis.

That being said, competition in the market place has changed significantly, from the outside. We can’t rely on the “gold plated” referrals from our GP colleagues like we once did. Second opinions are becoming the norm. We have one chance to develop a relationship while we present our treatment “design”.  We deal less with patients and more often with consumers.  Where we used to do exam / records / consultation on separate visits, the sequence has evolved for many of us into a single visit. We used to show our beautifully finished cases with plaster models and photos, or cut and pasted smiles from the AAO smile library and so forth. Today’s consumers want more.

The advent of CAD/CAM treatment planning and design software is changing all that.  We now have the ability (and even possibly the responsibility) to do virtual treatment planning, trying out options and alternatives with accuracy and predictability. The ability to customize everything about treatment from the beginning goes beyond the capability to modify and adapt the otherwise generic prescriptions and archforms of the past to match the particular patient’s needs.

Tens of thousands of patients have seen their clear aligner predictions or pre-bent setups. This is changing the exam and consultation process. Patients are becoming aware that we can show them what their teeth will look like post treatment. An interactive approach to smile design and occlusion function is not only possible but a significant advance in marketing and patient appreciation of what goes into their treatment plan beyond just straight teeth.

For purists, one of the leaders in CBCT scanners is currently beta testing 3D integration of IO scans with CBCT imaging and computerized jaw tracking.

There are stand-alone software that permits visualization and treatment planning of IO scanned data, and some IO scanners come bundled with similar software.  Some scanners are not only able to directly scan to aligner companies, but also come bundled with “Treatment Simulator” software.

While I am invested primarily in a single technology, I routinely use several of these and am doing trial runs of others. The learning curve is not terribly steep for any of these. And they all work.

The logistics of same day exams with IO scan and treatment simulation becomes the biggest hurdle.  We do an office tour ending with a CBCT (with face scan) and photos, if the IO scanner is available and the patient has time, we do an IO scan. This combination takes 30-40 minutes (as opposed to 20-25 without IO scan). While we review CC and get acquainted, everything is loaded.  The treatment simulation is run in the background (the 3 treatment algorithm choices are preselected).

After we have reviewed my diagnosis we look at the treatment simulation and start moving teeth to reflect my recommendations and patient wishes.  This not only increases patient engagement but shows that I am intimately involved in the treatment design, not just letting the computer treatment plan for me. It helps explain tooth size discrepancies and why IPR may be necessary (even on extraction cases). We can measure expansion and torque requirements and cuspid inclination. And it is especially useful for pre-restorative setups; visualizing spacing and vertical setup, bonding undersize laterals, etc.. Multiple treatment scenarios can be done to help illustrate trade-offs in compromise cases.

Not only is there improved communication with and education of the patient/parent, but a unique understanding of the case above and beyond the “Old Days” where I fondled a set of soaped and polished study models or CR mounted models.

Finally, we can re-establish our reputation with consumers as the experts in orthodontics by using and properly explaining to them the benefits of this technology.

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.

X-Rays: If You Take Them, Read Them!

By Dr. Greg Jorgensen
Rio Rancho, NM – www.gregjorgensen.com

Radiographs, whether the oldest film-based bitewing or the newest digital 3-D cone beam scan, are important diagnosis and treatment planning tools for orthodontists. They allow us to visualize anatomic structures and relationships that cannot be examined in any other way. The American Association of Orthodontists suggests that its members follow the ALARA principal (As Low As Reasonably Achievable) when it comes to the amount of radiation to which they expose their patients.

The value of radiographs as a diagnostic tool is indisputable. X-rays allow orthodontists to see pathology, monitor development, and diagnose skeletal and dental relationships that are at the root of malocclusion. Not a day goes by in my office where I don’t find something of importance in a radiograph that was not visible to me clinically. I believe that most orthodontists diligently read radiographs taken before treatment and between phases because they are in their “diagnostic mode.”

Dental radiographs are also essential to doctors during the treatment planning phase. The number, condition, and position of unerupted teeth affect the timing and scope of orthodontic treatment. The skeletal relationships revealed by lateral cephalograms help orthodontists select the appropriate treatment plan and biomechanics. While many orthodontists routinely evaluate radiographs taken specifically for treatment planning, others delegate the tracing of “cephs” to staff members who are not trained to recognize pathology. Many doctors study the results of the cephalometric analysis without actually seeing the film from which it was derived.

The data set created during a cone beam scan is useful not only for the evaluation of disease and the localization of important structures, it can also be used in the fabrication of orthodontic appliances before, during, and after orthodontic treatment. Examples of such appliances include digital models, indirect bonding set-ups, custom arch wires, and retainers. Some would argue that exposing patients to additional radiation solely to avoid taking alginate impressions is a clear violation of the ALARA principle. Some technology however uses the CBCT scan not only to fabricate an appliance, but also to visualize the current position of the roots in the alveolar bone and predict the effects that specific movements will have on the health of the teeth and the bone. That is revolutionary! Doctors using this technology would argue that this use of radiographs provides patients with the most accurate and healthy results currently available at a reasonably low radiation level.

Another timepoint just as important as before and during treatment is at the end of treatment. “Final records” are too often considered a mere legal record of what was accomplished during treatment. These records however also provide the orthodontist with information about wisdom teeth, changes in root length and bone support that occurred during treatment, as well as other non-treatment related pathologies that may arise while the braces were in place. Final records should be analyzed as carefully as initial ones.

Whether you take an x-ray to look at developing teeth, evaluate jaw growth, or as part of the diagnosis, treatment planning, and appliance fabrication process, you have a responsibility as a doctor to review all images and inform patients of any abnormalities present. A formal chart entry should always be made to document that you did review the radiographs taken whether or not you found anything out of the ordinary. While most of us are very comfortable evaluating routine panoramic and cephalometric films, today’s CBCT scans oft times include expanded field of views that include areas of the craniofacial complex with which we are not as familiar. The AAO’s Council on Insurance recommends that we seek the opinion of a qualified dental radiologist anytime we are not comfortable interpreting a diagnostic film.

Dental radiographs are important diagnostic tools. They not only help us diagnose and treatment plan orthodontic problems, they can also save teeth, bone, and even lives. They are useful however only if they are read. If you take an x-ray, make sure you read it!

The Rise of Digital Orthodontics

By Anthony M. Puntillo D.D.S., M.S.D.

 

The Industrial Revolution of the mid seventeen hundreds to the mid eighteen hundreds ushered in numerous social, economic, and cultural improvements to the everyday lives of people of the day. Along with these improvements also came disruptive forces. Businesses had to adapt to the new way of doing things to stay competitive. The modern Technology Revolution is having similar beneficial and unsettling influences on our lives. Technology is being employed to improve the efficiency and effectiveness of virtually every aspect of our society. In the field of healthcare, we have seen the mapping of the human genome, improved medical imaging techniques, and robotic surgeries. Modern orthodontics has also incorporated digital technology to improve the accuracy of orthodontic diagnosis and treatment planning. As the quality of and methods for obtaining digital data have improved, so has the orthodontic specialist’s ability to use this data to improve the level of care he can provide his patients.
Two examples of recent technology that have changed the way orthodontists provide care are intraoral scanning devices and three-dimensional Cone Beam Computed Tomography or CBCT. There are several intraoral scanners currently available. These machines typically use visible light and an intraoral “wanding” procedure to create very accurate three-dimensional digital dental models. It is possible to use these 3D models not only to diagnose, but also to fabricate active clear plastic aligners and other treatment appliances. Invisalign, Insignia Clearguide, and ClearCorrect are examples of aligners systems created using digital models. SimpliClear is a digitally designed clear biomer wire fabricated with adjustments bends already in place. Insignia uses digital data obtained from an intraoral scan to create patient specific brackets and custom bracket placement jigs.

Patients can benefit from intraoral scanner technology by avoiding the impression procedure and by the improved accuracy of the appliances provided by their doctor. Orthodontists benefit by the elimination of costly impression materials and the improved efficiency of digital models. One shortcoming of intraoral scanners however is that the models they create are limited to supragingival tooth structures only.

Orthodontists are interested not only in the alignment of the crowns of the teeth, but also how the entire dentition (including the roots) are positioned relative to the supporting bone and facial structures. Using cone beam (CBCT) technology, orthodontists now have the tool they need to evaluate the alignment of the teeth in three dimensions. There are several CBCT machines and software programs currently available that enable orthodontists to view the teeth and supporting structures in all planes of space. This alone can improve orthodontists’ ability to diagnose and treatment plan to the benefit of their patients. There is now one system available (SureSmile) that incorporates the bone data from a CBCT scan into its digital 3D models. This allows orthodontists to make better treatment planning decisions regarding the roots of the teeth by revealing the limits of the supporting structures. The software can then follow the orthodontist’s “prescription” to robotically generate custom archwires containing every necessary tip, torque, and angulation needed to finish the treatment.
The rise of digital orthodontics has also spawned a resurgence in lingual orthodontics. The ability to digitally create custom brackets and wires (i.e. Harmony, Incognito, Suresmile QT, etc.) has made it easier for orthodontists to manage the intricacies of lingual treatment. Consequently, an increasing number of orthodontists are now offering lingual treatment options to their patients.
Technology has drastically increased the pace of change in our society. As orthodontists adapt and incorporate technology into their practices, their ability to provide better treatment for patients will also increase at an exponential rate. It is our challenge and obligation as orthodontic specialists to identify and evaluate new technologies, and when appropriate incorporate them into our patient care in a cost-effective manner.

Cone-Beam CT Dosimetry: Making Sense of it All

By Aaron Molen

There continues to be controversy inside and outside our profession on how much radiation exposure is justified in the pursuit of diagnostic information.  In the end there is no golden answer that will address every situation and ultimately I cannot tell you what’s appropriate in your office.  However, I can arm you with information that will enable you to make an educated decision regarding what’s best for your patients.

Effective Doses
There are many publications and websites that try to accurately compare effective radiation doses, but it’s not that simple.  For example, there are two ways to quantify effective radiation, the ICRP 1990 recommendations and the ICRP 2007 recommendations.  The 2007 recommendations give more weight to the salivary glands, skin, and other organs than before which results in effective doses being higher when measured using the 2007 recommendations. Most publications, though, use the 1990 recommendations which were written before the release of the 2007 recommendations.  Comparing 1990 to 2007 based doses is like comparing apples to oranges so you should double-check which method is being used.

Secondly, the absorbed dose of a CBCT system varies widely within the system itself based on the FOV, scan time, kVp, and mA settings used in the scan.  Recognizing this is important because sometimes CBCT manufacturers will report their scans with the lowest radiation dose and the scans of their competition with the largest radiation doses.  It’s paramount when comparing effective doses between different systems to standardize the previously mentioned settings as much as possible to create a fair comparison.

Finally, the radiation dose measurement depends on the phantom used by the company, or researcher, to measure the dose.  There are a number of different phantoms available that can have a varied number of sensors placed in them to measure the dose.

It’s for the above reasons that I will not be discussing specific radiation doses in this blog post since I believe with all these variables it can be like comparing apples to oranges.  Instead when the time comes to make your decision as to which machine to buy or use I would encourage you to use the information we’ve thus far discussed to filter through the always changing information available in peer-reviewed journals or in the published material from the manufacturers themselves.

Using Cone-Beam in Your Office
Each orthodontic practice has its own unique set of patients and each doctor uses their own personalized treatment approaches to delivering the best care possible to their patients.  Since each practice is unique, each practice will also use cone-beam differently.

In keeping with the ALARA principle I believe orthodontists should answer the following questions before taking a CBCT scan: (1) How does the dosage of this specific scan compare to my normal 2D radiographic series; (2) Does the additional 3D information have the potential to change my treatment plan; and (3) Does the additional 3D information have the potential to create a better treatment outcome for my patient?  How you answer these questions will determine for each patient whether taking a CBCT scan is warranted in their unique case.  Since each office has their own unique set of patients and uses their own unique treatment modalities, some orthodontic offices will take less scans than others.  In the end the goals of protecting our patients, while delivering the best treatment outcomes possible must be balanced by each orthodontist.  Hopefully with the information I’ve provided orthodontists can find that balance with more confidence.

Who moved my DICOM?

by Juan Martin Palomo DDS, MSD
palomo@case.edu

Most orthodontists associate the term “DICOM” with Cone Beam Computed Tomography (CBCT).  DICOM however represents much more than that.  DICOM, which stands for “Digital Imaging and Communications in Medicine,” is the international standard for all medical images and related information.  Any radiograph, 2D or 3D, as well as photographs and even text documents can be stored as DICOM files.  DICOM represents is a non-proprietary file format that can be accessed by any software regardless of the hardware and software used in the capture stage.  Think of it as the equivalent to a .jpg, .tif, or .pdf, with many extras. Most importantly, it replaces company-specific file formats making data accessible by anyone in the healthcare field.

Many of us have had to at some point in time change management software systems, or send information to referring or transfer offices.  This would be very simple if everybody involved used the same software or if all software read the same formats. When this is not the case complications may occur.  Software programs use their own proprietary file formats because 1) they have invested a lot of time and resources to make the files efficient, and 2) they want to protect their intellectual property.  This can be a shortcoming to the user if there is no option for exporting the data in a format that can be opened with other programs.  It is important for anybody buying clinical software (regardless if it comes with x-ray equipment or not) to make sure that not only can it read DICOM files, but that it is able to export data into that format too.

A DICOM file has multiple layers of information embedded within it.  A DICOM file contains the patient’s name, demographics, information about the capture system, the date, etc. So a DICOM file located on a computer hard drive is much better than an unlabeled radiograph or picture laying on the desk. It has all the identifying information embedded within it.  This is obvious when a DICOM file is opened and the patient’s personal information is quickly displayed.  Additionally, most DICOM viewers also use the data embedded within the file to assign the patient’s identity, helping avoid the mismanagement of images (i.e. placing the wrong image into a patient’s file).  If your current software does not read DICOM files, don’t worry.  There are plenty of DICOM readers free of charge that can be easily downloaded that will perform most necessary tasks.

Lastly, when archiving images, make sure to do so in the DICOM format because there is no guarantee that your specific software will be available forever.  I would further recommend that you go back to your previously archived files and see if they are in the DICOM format. Don’t be surprised if they are not!  Luckily most, if not all, dental and medical capture devices now provide a “save as DICOM” option. Just be aware that DICOM is not usually the default.