Fix or Replace That Digital X-Ray?

By Bryan Delano

The film X-ray era is fully behind us, and we are now entering the second and third generations of digital 2D panoramic/cephalometric technology. The first models of digital X-rays, available in the late 1990s, were film-to-digital upgrades. In the early 2000s, direct digital 2D options were introduced. Today, practices have the option of implementing either new or pre-owned digital X-ray technology at a fraction of the cost of just ten years ago.

As some digital panoramic models reach almost twenty years of age, and most first-generation cone beam units are over ten years of age, warranties have expired, repairs are more frequent, and the cost and availability of parts is challenging. Additionally, software drivers that control these units are not keeping up with modern computer operating systems, limiting available compatible options in the event of a PC failure. When faced with these obstacles, a practitioner has the option to either invest in a costly repair or purchase a replacement unit.

Just like any modern technology, repairing an X-ray unit can range from a ten-dollar simple fuse replacement, to tens of thousands of dollars when replacing a failed sensor. Please see the guidelines below when faced with X-ray component failures.

Digital sensor failure

Unfortunately, there are few, if any viable sensor repair resources, so the replacement of the actual sensor is often the only option with a digital sensor failure. Some X-ray models such as Sirona, Planmeca and Instrumentarium are formatted with cartridge-type sensors that can be moved between pan and ceph. A pan sensor can only be used to capture a panoramic image, but a cephalometric sensor can be used to take a pan OR a ceph. Switching the sensor between the pan and ceph is easy and can provide a long-term solution or can buy time to research other options. It’s never good to feel pressured to make an expensive purchase quickly, so this option can help extend the decision-making period. Purchasing a new sensor can range from $3,000 to $15,000, depending on the manufacturer, but there are other options to consider. For example, often you can find X-ray sensors on eBay that offer Buyers Protection. This allows a buyer to receive the sensor, test it thoroughly, and return it for a full refund if it is defective.

We don’t know what is wrong

Many dealer technicians rely on the X-ray manufacturer for support. When your tech arrives, they inevitably will immediately contact the manufacturer for help. The older generation machines are often misdiagnosed at this point, and the tech will suggest ordering or trying up to several parts, which can be very costly. Some of these parts may be needed and others will not. The challenge of only ordering one part at a time could result in delayed repair time with multiple shipments and on-site tech labor charges. When ordering several parts at a time, however, make sure to ask if the unused parts be returned for full credit or a refund with a re-stocking fee, or if they cannot be returned at all. Major replacement parts can cost anywhere from $3,000- $10,000 (not including service), even if the sensor is not involved. Warning: Buying parts other than sensors on eBay can be limited or difficult, and often dealer technicians will refuse to replace these parts due to liability issues.

I’m sorry, this unit is discontinued, and parts are no longer available

By law, X-ray manufacturers must make parts and support available for their equipment for around eight years after the machine was last sold. For example, if your machine was manufactured in 2007 and sales stopped in 2010, they are obligated until 2018 to provide replacement parts and support. That doesn’t mean if your machine is dated 2007, then you are already out of luck. If that model is currently still manufactured, then you have a long runway for parts availability. Many manufacturers are still providing parts and support beyond the eight required years, but the challenge for them is that these parts were not made by their own company, but by third-party suppliers. If those suppliers choose not to continue manufacturing the desired part past the eight-year requirement, then the X-ray manufacturer is left with only the parts that they have on their inventory shelves. This is a common issue with many X-ray manufacturers.

Replacing the unit

Replacing an X-ray unit is a costly proposition. Fortunately, digital panoramic unit pricing has come down significantly in recent years. In addition, many quality pre-owned X-ray options are also available. The challenge now becomes that your X-ray is down and you need a replacement in a short period of time. This time factor could limit your options and ability to negotiate the best price. Many X-ray manufacturers have ended exclusive distribution deals, so you can shop for the same X-ray model from several distributors for the best pricing. Depending on the repair status of your current unit, you may be able to receive some trade-in value based on the remaining parts. Perhaps this is the practice’s impetus to choose and upgrade from 2D to 3D. If you want to “buy” some time for additional research, you can also ask the new / used X-ray vendor to fix your unit with borrowed / loaned parts until the new X-ray is purchased.

So, when faced with the challenge of repairing or replacing your X-ray, ask yourself the following questions:

  • What are the costs of the repair? Do they exceed the costs of purchasing a new or pre-owned unit?
  • Can I get away with “patches” such as swapping a sensor between a pan/ceph unit or buying parts on eBay?
  • If my X-ray is over eight years old, are parts still available?
  • Can I allow enough time to research my options and compare pricing between vendors?
  • Is now a good time to consider upgrading from 2D to 3D?

When possible, the best practice is start planning ahead for older X-ray equipment replacement. But, since you cannot always predict equipment failures, it never hurts to start researching your options today.

 

 

Sharing Cone-Beam CT Images Online

By Dr. Dan Grauer

When diagnosing and treatment planning interdisciplinary patients, have you ever sent your three-dimensional images to a colleague? Have any of your patients requested a copy of their records for a second opinion? Or maybe, a patient declines a radiograph because another orthodontist has recently taken a CBCT image of the patient? In all of these instances, you will need to communicate with the other office to initiate the transfer of CBCT images. The purpose of this blog is to describe different methods used to share patients’ CBCT records via online means.

Images acquired in your office are requested by a second orthodontist/dentist:

The first question that will need to be answered is whether the other office has the possibility of viewing and analyzing the images in three-dimensions. In a few instances, I have found myself trying to transfer a full three-dimensional file, when the second orthodontist just wanted a cephalogram and a panoramic radiograph. If this is the case, your software will probably allow you to create a synthetic cephalogram and panoramic radiograph that can be emailed through a HIPAA-compliant email account. If the second orthodontist requires a three-dimensional image, two case scenarios are possible:

Case scenario 1: Second orthodontist owns software to read and visualize CBCT images.

In this case, your software is able to export the CBCT Images in DICOM format (Digital Imaging and Communication in Medicine). DICOM files are large, and a file transfer application is needed. Once transferred, these can be imported into the software of the second orthodontist for visualization and analysis.

Case scenario 2: Second orthodontist does not own three-dimensional imaging software.

Under this case scenario, the second orthodontist would need both the CBCT images and a three-dimensional viewer. Three main options are available.

Option 1: If you own a CBCT machine, your software is generally able to create a file that includes both the image data and a basic viewer. The files created are large and can be transferred with a file transfer application.

Option 2: Anatomage offers the possibility of uploading your CBCT images to the cloud, and these can be accessed online through Anatomage’s application, which acts as a visualization tool. At this point the software is in Beta-version and can be accessed at www.anatomagcloud.com. You, as the generating office, will need to upload the images to the AnatomageCloud database and use this application to allow the second office to access the specific patient images. The access is granted with a link embedded in an email. After receiving authorization to access the images, the second office will be able to access the images online without the need of downloading them or installing any software.

Option 3: Dolphin Imaging software offers a complimentary viewer, https://www.dolphinusers.com/dolphin-imaging-viewer/. The receiving doctor can view 3D images by downloading and installing the Dolphin Imaging Viewer software. Files are transferred in DAZ file format. This file format is proprietary to Dolphin Imaging, and the files are created by the originating doctor through Dolphin Imaging 3D Software. This option 3 would work also in Case Scenario 1, when both doctors use Dolphin Imaging 3D software, but it is important to note that only the unprocessed images need to be transferred, such as the DICOM file; the viewer is part of the software downloaded by the receiving office.

Images acquired by other offices:

Images that you receive from other offices should be requested in DICOM format. This will permit you to be able to import these into your 3D software. If you obtain the file in a different format than DICOM (that often includes the viewer), the analysis and measurement possibilities are limited; this is because your 3D software most likely includes all the features that you may need while visualizing and measuring 3D Images. If both offices use Dolphin Imaging 3D Software, a proprietary format DAZ can be used to transfer and share images. The advantage of this approach is that all patient images, including both 3D and 2D images, are shared simultaneously.

In summary, with Cone Beam CT becoming more popular in practices, sharing 3D images with other treating doctors or practices requires some additional steps. The first step is to initiate the conversation with the second office to establish the best system to use to share images. The advantages of 3D images over traditional 2D images are beyond the scope of this blog, but once you become accustomed to a transfer and visualization system, the collaboration between doctors and patient care may improve.

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?

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.