The specialty of orthodontics has been waiting for a joint committee of orthodontists and periodontists to report to the profession on its recommendation regarding this question. Where is this report?
It is not ethical to take a CBCT image on every new orthodontic patient in private practice. Furtermore, it is not even ethical to take an OPG and a lateral cephalogram, and maybe even a postero-anterior one, on every new ortho patient.
As usual is the clinical examination that guide the decision whether to request radiological examinations, meaning that although it could be minimal, there is always a risk due to the use of x-rays, then the diagnostic benefits obtained from each singular patient must outweigh the risks which he is exposed by using such diagnostic tool.
On the other hand, as we heard at the AAO congress in Philadelphia, technological development is constantly evolving and today it seems that there is a new CBCT scanner that really administer a dose equivalent, if not lower, in terms of microsieverts to that associated with the use of classical OPG and lateral cephalogram digital two-dimensional images.
In this case, in a patient in which it is necessary to perform these two radiological exams, it would be more ethical the use of this CBCT scanner.
For clinicians who do not have access to this specific scanner, but to scanners with x-ray doses that are very different depending on the type of scanner and the type of the scanning program setting, it is essential to fully understand the characteristics of the scanner used: a higher dose of radiation can be justified if the additional informations that the clinician obtains are crucial in the development of a therapeutic program.
It is not ethical to take a CBCT image on every new orthodontic patient .
The American Dental Association (ADA) and the FDA recommend that clinicians perform dental X-ray examinations, including dental CBCT, only when necessary for the diagnosis or treatment of disease.
The Medical Services Advisory Committee (MSAC) Australia DAP 2012 ( Final Decision Analytic Protocol ) relates to the use of CBCT for the following indications:
• to assess bone quantity and quality as part of dental implant planning and in management of suspected implant complications;
• to assess structures identified clinically or on 2D radiographs as being in close approximation to sites of planned dento-alveolar surgery that may be at risk of damage during surgery; and
• further assessment of the dentition and associated dento-alveolar and TMJ pathology which may not have been adequately assessed using two-dimensional radiographic techniques.
Patients considered for CBCT would normally have had the following interventions
• a private dental consultation(s);
• intra-oral radiographs; and/or
• panoramic radiographs conducted by a suitably qualified health professional such as a radiologist. (http://agencysearch.australia.gov.au/search/search.cgi?query=cone+beam+computed+tomography&collection=agencies&form=simple&profile=msac)
Thank you for these very inviting comments which I am also in agreement with. I think proper comparisons should also be made. A lot of clinicians are saying the dosage is comparable, but is it with a standard digital or analog pan/ceph? It bothers me when this technology is used in practices for the "Wow" factor.
I don't think it is ethical to take a CBCT image on every new orthodontic patient not only in private practice but also in University Hospital except for special patients.
No. It is not ethical to take a CBCT image on every new orthodontic patient in private practice. All CBCT examinations must be justified on an individual basis by demonstrating that the benefits to the patients outweigh the potential risks.
http://www.sedentexct.eu/system/files/Dr%20Rushton.pdf
No, I do not think it is ethical or necessary to take a CBCT image on every new patient requiring orthodontic treatment whether in private, public or teaching institutions. LIke any other radiological investigation, CBCT is an invasive investigation and poses a certain risk to the patient. Though small, the reality is that this risk is there and probably varies with every patient. The need for a CBCT being taken should be determined based on the findings of clinical examination and plain radiographs with less radiation dosage. CBCT should only be done if it will help in the diagnosis and treatment planning of the patient when this diagnosis cannot be satisfactory obtained from the plain radiographs.
i'm from italy so my point of view is "european"
in italy, but also in most of the EU counties, first of all it's not legal for a dentist to take a CBCT to all patient. the european low that governs the use of x-rays is very severe; especially for dentistry. each time we have to see if an alternative exists.
i'm in the regional board of the medical association, and also from this side i have to say that ( in italy ) our ethical code does not allow to use wholesale diagnostic.
from a personal point of view, each time i ask myself which information i'll get from the record and if it's really necessary for the patient first and for the treatment second.
many times i prefer to have a cone bean at the end of treatment for verify my results.
If we look from todays perspective.. yes it is unethical to advise CBCT scan for every new patient. Tomorrow may be yes, when the
effective dose reduces from about 100 to about 10 to 15 microsieverts. The radiation dose is fast reducing with measures taken by
companies. There is ver interesting invited review article by Makhija and Makhija which concludes with following remarks
"CBCT with 3D volume rendering provides all the necessary information in a single radiologic study and generates clinically accurate
and immediately available images to get the virtual 3D patient which can be evaluated again and again by same operator or different
operators till diagnosis is finalized or treatment planning is finalized. Not only that, it can be used in future for comparing the outcome
of treatment with another CBCT. It has educational, communicational advantages and serves as life time record. Even the areas which
were not intended for study can be seen checked for incidental findings which may be beneficial from patient point of view. May be,
Training in basics of CBCT and 3D anatomy will become essential part of dental curriculum in India in coming years.
Although presently CBCT is not prescribed in each and every case of dental treatment, CBCT scan is going to become essential
diagnostic aid in near future to analyze each orthodontic case from start to finish, for digital diagnosis, planning anchorage,
orthodontic VTO, biomechanics, brackets design and fabrication. Virtual digital articulators will be part of each patient to study
functional examination and check mandibular movements, occlusal interferences, distribution of forces of occlusion, checking
occlusion on digital models for success and finishing of orthodontic treatment and at the end, retention planning and fabrication of
retainers."
The article is available from http://www.bujod.in/www_bujod_inupdates2/Article%208.pdf
It is ethical when it is indicated and unethical when there is no indication so it is case dependant
Not on a routine basis but as in all aspects of ortho treatment there are situations that we will need a cbct in order to make a more thorough diagnosis
In Italy the situation is very well descrived by the collegue Franco Bruno ; I think too that it's not ethical take a CBCT for every new patient but the great data acess permitted with CBCT for the present and for the future of the patient needs an effort to present this alternative to the new patient
No, I do not think it is ethically defensible to take CBCT on every patient treated with orthodontics. But it's totally ok to CBCT for patients who are to undergo orthognatic surgical intervention. This simplifies 3D programming.
Do I believe it is ethical to take a CBCT image on every new orthodontic patient in private practice?
Given that epidemiologists indicate that at least 46% of the general public (depending upon whose survey you choose to believe) will never need orthodontics, I have always thought that the specialty’s suggestion that “All children should have an orthodontic consultation by age 6” was self-serving – to say the least. Probably the best “age” to provide as a guideline would be “once the four permanent lower incisors have erupted.” By then you can perform a Mixed Dentition Analysis; and, by then, not only will you have more information about alignment and spacing or crowding, but you will be able to determine if a child will have a full component of teeth.
By that age, probably the best indication for an orthodontic consultation would be to be able to provide information to anybody (a family dentist, a parent or the child) who might have a concern as to normal development of the teeth: pain or dysfunction, general alignment issues, esthetics or any other CONCERN.
Now, with the patient presenting for a legitimate concern; that patient should receive a legitimate examination. The various components of a proper exam should include a comprehensive evaluation, one that includes a minimally invasive but comprehensive radiographic appraisal. Some of the newer technologies can provide a multitude of images for much less exposure than a standard panoramic x-ray has in the past. As part of the diagnostic arsenal of a contemporary practitioner, a clean radiographic evaluation is an essential component of preventive orthodontic care. Spinning 3-D images will never be.
No, I do not think it is ethical or necessary to take a CBCT image on every new patient requiring orthodontic treatment whether in private practice, public or University Hospital.
To answer "should CBCT be taken for every patient"? three preceding questions must be asked:
1) What are the indications that warrant CBCT investigation? Asked another way: which conditions would CBCT imaging change my diagnosis and treatment plan?
2) What are the incidence of these "warranted indications"?
3) What must be the background frequency of "warranted indications" before we can reasonably justify taking CBCT for everyone? 10%? 25%? 50%? ...Asked another way: how often am I willing to miss-diagnose and inappropriately treat due to insufficient diagnostic information?
In my opinion, there are 9 evidence-based conditions for which diagnostic information from CBCT vs 2D imaging could change my treatment plan:
1) airway / clinical signs and symptoms of sleep disordered breathing
2) asymmetry / occlusal cant
3) history of dental trauma
4) impacted teeth
5) ectopically erupted teeth (= increased likelihood of adjacent root resorption)
6) evaluate midpalatal suture for RPE vs SARPE
7) orthognathic surgery
8) planning TAD placement
9) TMJ evaluation
While I'm not completely comfortable with taking CBCT on all patients, the background frequency of this list is startlingly high... high enough to make me re-consider whether CBCT perhaps should be routine
2D radiology often provides alarmingly poor diagnostic information. This too must be considered in the 2D vs 3D debate. A recent study (Granlund EJO 2012: 34; 452-7) found a 96% error rate in reading 2D panorex. Of these errors, 24% would have resulted in different orthodontic treatment plans.
Again, I am not yet comfortable with taking CBCT for all patients, but the evidence is mounting that we should at least consider it... especially as the technology improves and CBCT radiation doses become lower and lower.
ethical is a big problem, but from another point of view. If you or me as an orthodontist, who take CBCT image as diagnosis tool, but did not notice or diagnose thoroughly for all information from CBCT image, such as endo or perio problem, or TMJ problems, then we might get into trouble. So taking CBCT for all new patient is an issue, but "the ability to making correct and comprehensive diagnosis" should be build up before we ask patient to take this image.
Please read the article by lodlow in the AJODO dec 2013. The reduction of radiation dose of CBCT's with a reduced field of view (FOV) will change the indication for traditional documentation (OPT and Headplate) into 3D radiographic images.
Provided that the quality of the Quick scan CBCT is sufficient for orthodontic diagnosis, treatment planning and treatment evaluation
Am J Orthod Dentofacial Orthop. 2013 Dec;144(6):802-17. doi: 10.1016/j.ajodo.2013.07.013.
Assessment of phantom dosimetry and image quality of i-CAT FLX cone-beam computed tomography.
Ludlow JB, Walker C.
Michael Major is right on point. It is never appropriate to take ANY radiograph as part of a "Routine orthodontic exam", not a pan, not a ceph, or CBCT. Could we treat patients successfully without any radiographs, probably so and the finished models might look great. The first question is "What are YOUR GOALS of Imaging?" after you answer that then what is the patient's chief complaint? then What information can i get from the clinical exam alone? What records do I need to answer specific clinical questions and only then begin a diagnosis and treatment plan(s)? If you believe you can get all the info you need from 2D radiographs, then that's your decision. If you agree with Michael's 9 Evidence-based conditions, which I do, then If I want information on Airway (medical HX of allergies, breathing problems, Long facial height, etc.) then I may want 3D CBCT to even be able to evaluate the volume and cross sectional areas of the airway, along with areas of possible obstruction (base of tongue, Adenoids, tonsils, etc). That can't be done on a lateral ceph. If I feel I need better info on the TM Joints (TMD pain patient, clinical signs, etc) , then a panoramic is not appropriate for what my "Goals of imaging" are. I totally agree with Michael's reporting the EJO article, which I also find in my practice, about 25% of the time it does change my treatment plan. That is 1 out of every 4 patients. So if you are OK with missing something 1 out of 4 times, then 2D may be adequate. The radiation dosage is now getting into the range of "traditional" 2D pan and ceph. Reducing the Field of View also reduces the dosage to the region of interest. I also refer you to the Article in the AJODO above in Hero Breuning's post.
It should be not considered a routine exam, but a second level diagnostic tool.
in the end it all depends on your treatment goals…if you are only looking at teeth and teeth are you obsession well you probably do not need modele,x-rays etc….just put on the brackets …now if your goals are airway,function(the importance of TMJ) periodontal stability there is no doubt that cbct is necessary…in all cases…probably not however with the new very low radiation cbct's that are coming out I am sure that in no time it will be routine in all of our practicas…if your goals are what they should be
I am not yet comfortable with taking CBCT for all patients, but there are same conditions to take CBCT for diagnostic information:
impacted teeth, ectopically erupted teeth (dental trauma)
planning TAD placement
orthognathic surgery
Of course not for every new patient. From orthodontic point of view, I do take that only for impacted teeth.
I agree CBCT should not be a routine exam, and should be limited to specific clinical situations (impacted teeth, orthognatic surgery)
I fully agree with Domingo Martin. As I said in my previous comment, Martin Palomo at the AAO congress in Philadelphia described his clinical orthodontic experience with the iCAT FLX, and now John Ludlow is presenting his results from a technical radiological point of view.
It's not correct to talk about CBCT in a generic way: every scanner has different properties and, when using the same scanner, every setting combination has its own features.
Technological evolution, as usual, is running more and more faster: in few years nearly all CBCT scanners will have a "reduced exposure" program that will truly administer a dose equivalent, if not lower, in terms of microsieverts to that associated with the use of classical OPG and lateral cephalogram digital two-dimensional images.
That day, the question "Do you believe it is ethical to take a CBCT image on every new orthodontic patient in private practice?" will almost be a meaningless question.
How can you give a comprehensive orthodontic consultation without eliminating the possibility of latent agenesis, transposition, impaction, ectopia, ankylosis, delayed formation or eruption - or other dental anomalies. If you want to facilitate the interceptive management of these problems, you have to know that they exist. How do you make such recognitions without some level of radiography? As Dr. Dalessandri so poignantly states, low dose CBCT is rapidly becoming the diagnostic tool of choice.
I,m also not enougth confortable in taking CBCT as a routine exam and also in children . To be in University , universitat Internacional Catalunya, let us know what are ours "Goals in imaging in orthodontics" and this can be , DAP as dental anomaly patterns, TMJ, AIRWAY, and for diagnosis and treatment planing in craaneofacial problems . I think In asymmetric patients is necessary to study how can you remove the dental compensations and know exactly the 3D movements of occlusal plan. Also is important to remember the incidental findings in this area (Cha JY, Mah J, Sinclair P. Incidental findings in the maxillofacial area with 3-dimensional cone-beam imaging. Am J Orthod Dentofacial Orthop 2007;132:7–14.). And if we follow ALARA concept , is correct to use CBCT pre and post for assessing treatment outcomes ?
I am not yet convinced taking CBCT for all my patients as a routin procedure unless technological advancement prove its superiority regarding patient,s safety.
No, I think it is not necessary for all patients, at the same time I should mention a patient with minimum of expected tooth movements to become ready for implant replacement of her missed lateral incisors. I expected a maximum of 14 months of treatment. After 16 months of treatment, I sent her for a CBCT and found that the roots of most teeth are in compact bone making it clear why the teeth were moving so slowly. this is my only experience in 23 years of orthodontic treatment.
Now that CBCT radiation dose can be 1/2 or less than the dose of a digital panoramic xray, and exponentially higher for the knowledge and information gained (ie the anatomic truth) such as the anatomic truth of the boundary conditions within which we as orthodontists move teeth in all 3 dimensions, root length and root alignment (parallel or not) which had been shown over and over not to be reliable on standard panoramic xrays. The quality of the bone surrounding the teeth which Allahyar mentioned above. We find airway issues, between 25 to 30 % of the time, bad enough to refer to an ENT. This is a health issue and we as orthodontists may be the first to pick these problems, not to mention the negative effects of airway obstruction has on facial growth. 2D imaging may be adequate for certain cases, but how do you know from a clinical exam? You don't know what you don't know. I personally find greater than 80% of the time on the cases we image with 3D CBCT, findings that either make a difference in my treatment plans or are a health issue that needs to be evaluated by other health professionals. Any radiation exposure should be evaluated as to the Lowest Dose and maximum information one will receive from any XRAY exposure whether it be 2D pan / ceph or CBCT ( The ALARA principal). See Dr. John Ludlow (UNC) recently in the AJODO and also i hope you saw his lecture at the AAO meeting last week. If not you can get a copy on DID from AAO. Also look up Dr.Sean Carlson's ( he is in Walnut creek Californis) Utube videos on his Web site on radiation dose an related to Loss of Life Expectancy . He has 4 videos. I highly recommend everyone look at these videos and Dr Ludlow's articles.
Interesting interview with José Rino Neto who concluded saying "use of 3D images generated from the CBCT scansare worth the risks when used with responsibility and knowledge by the orthodontist"
ref:
Ramos Adilson Luis, Queiroz Gilberto Vilanova, Paiva João Batista de, Valladares Neto José, Macoto Roberto. An interview with José Rino Neto. Dental Press J. Orthod. [serial on the Internet]. 2013 Feb [cited 2014 May 26] ; 18( 1 ): 8-29. Available from: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S2176-94512013000100005&lng=en. http://dx.doi.org/10.1590/S2176-94512013000100005.
I believe it could be justified if it will be used for orthognathic planning/surgery or for extractions.
CBCT imaging is indicated in bimaxillary proclination, open bite, and compensated Class III malocclusion and craniofacial anomalies (e.g., cleft lip and palate, craniofacial synostosis).Other indications are abnormal root morphology or resorption (in the mixed and permanent dentitions), surgical exposure (in children > 11 years) when location of the crown cannot be determined clinically or with conventional 2D images, interceptive orthodontic treatment for children ( 5-11yrs), locating developing teeth prior to alveolar bone grafting in children with oral clefts and in preparation for craniofacial surgical procedures.Otherwise routine use of CBCT is not justified.(Journal of Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology
Volume 116, Issue 2, August 2013, Pages 238–257)
I think in very near future cbct will be required in each n every case for diagnosis n treatment planning. Scanners with least radiation will have to be chosen. As cbct scan give anatomical model of teeth with roots, customised simulations leading to printing of customised brackets with 3D prescription of tip torque in out will become routine. Treatment results with proper root position can actually be confirmed before actual treatment. Occlusal forces, intercuspations, FEM analysis of each case and biomechanical planning will definitely outweigh any negative thoughts about cbct. I fully endorse routine use of cbct only after taking into cosideration various guidelines for safe use in existance and selecting good scanner, FOV, proper software, proper graphic card in workstation and hitech cad cam apparatus
We begin with a 3D face capture (stereophotogrammetry ie. 3DMD). Evaluate Biomarkers on the 3D face for potential allergy/airway signs, asymmetry, smile esthetics, facial morphology, etc. The evaluation of these Biomarkers help me decide if 2D xray imaging (ie. Ceph & pan) is adequate or if we need more detailed diagnosis using CBCT. We find about 30% of the time we are referring both children and adults for airway issues to ENT or Pulmonary MD (tonsils, adenoids, sinus pathology such as maxillary, sphenoid, ethmoid, etc.) These MDs can operate using my CBCT images and do not need traditional medical CT prior to surgery, if needed. We give the DICOM data to the patient to take to their pediatrician, ENT etc. For further evaluations.
In the present state of technology, I do not believe that every patient has to take a CBCT exam. It should be decided according to the severity of patient`s treatment plan.
But if the levels of radiation, one day reaches a level similar to traditional, multi-exposures of orthodontic documentation, there are no doubt that the amount of information regarding the alveolar bone, torque control and even individualized prescription of brackets can be of benefit to most patients.
It becomes a mistake, to take a CBCT to analyze it in the same level of information (same angles and measurements) that a bi-dimensional cephalometry can propitiate.
Careful dosage and ionizing radiation should be used only in specific clinical conditions such as impacted canines, supernumerary teeth and temporomandibular joint arthritis, and in planning orthognathic surgery.
Canine impaction is one of the clinical conditions in orthodontics for which evidence-based research for the clinical application of three-dimensional (3D) imaging exists. The primary indication for the low-dose CT, intact, was to evaluate the position of displaced intraosseus canines in the maxilla.
In our University we are specialized in the treatment of impacted canines often associated with other dental anomalies such as supernumerary teeth and missing or peg-shaped lateral incisors. The imaging protocol that we use was carefully planned with our radiologist to minimize patient dosage in low-resolution and small field of view (FOV) image acquisitions.
It is worthwhile reading answer by Won Moon to a similiar and specific question " What do you think about the ideal cone beam protocol for orthodontic patients? With the radiation concern, do you think we should request a 3-D scan for every orthodontic patient? see page no 20 in following citation
Moon W. Interview. Dental Press J Orthod. 2013 May-June;18(3):12-28
Radiation dose from iCat FLX for Orthodontic diagnosis is now as low as a single 2D digital pan (8 to 15 microSv) and lower than traditional 2D digital pan/ceph (26 to 36 microSv), with exponentially more significant information. A recent article by John Ludlow from U. North Carolina, in AJODO 2013 144(6) documents radiation dose info from various CBCT units. See my article co-authored with Sean Carlson in Orthotown Sept 2011 titled " The Truth about CBCT radiation". In 2014 these dosages are lower than we reported in 2011. Also read an a riptide I co-authored with Sunil Kapila & Scott Conley in Dento-maxilofacial Radiology on The Current Status of CBCT
Low dose units are out now. Example iCat FLX settings for orthodontic diagnosis is now LOWER than a traditional 2D Pan & Ceph. see John Ludlow , University of North Carolina, article in AJODO. Also if all you are doing in ortho is creating "pretty smiles and beautiful faces" then 2D might be adequate. If you are wanting more information and knowledge on the TMJs, the Airway, obstructions of the Airway, Sinuses, impactions, boundary conditions of the alveolus, skeletal transverse deficiency and other "incidental" findings, that may not influence your orthodontic treatment plan, but may be a significant health issue for the patient, after a thorough clinical exam and an educated decision, low dose CBCT may be indicated. Don't forget Airway issues influence craniofacial growth."You don't know what you don't know and what you can't see you can't diagnose." BH
Per AAOMR guidelines:
Localization of impacted teeth and identification of associated root resorption* » CBCT should only be used when Multi-slice CT is necessary, in which case CBCT is preferred due to lower radiation dose; or » CBCT should only be used when the question for which imaging is required cannot be answered adequately by lower dose conventional (traditional) radiograph;
Clef lip/palate* » CBCT should only be used when Helicoidal CT is necessary, in which case CBCT is preferred due to lower radiation dose;
Mini-implants: Proper mini-implant placement site* » CBCT are rarely necessary, except for cases with critical space left for mini-implant placement;
Severe cases of skeletal discrepancies » CBCT of the face might be used to develop orthosurgical treatment planning; » Preference is given to patients older than 16 years of age;
Pre-surgical assessment of impacted teeth » CBCT should only be used when the question for which imaging is required cannot be answered adequately by lower dose conventional (traditional) radiography;
Orthognathic surgery planning » CBCT of the face might be used to develop orthosurgical treatment planning;
TMJ assessment » CBCT should only be used when Helicoidal CT is necessary, in which case CBCT is preferred due to lower radiation dose;
However, for localization of maxillary impacted canines, the CBCT has highest accuracy 94% (Serrant/McIntyre 2014) compared to both H/V parallax.
All of that is true. But that and other Reports came out before iCAT FLX broke the radiation barrier, which can do 16x13 cm FOV down to 8X8 cm at 0.3 - .04 mm resolution at 4.8 sec ( pulsed NOT continuous) is between 8 to 24 micro SV which is around an average Digital Panoramic (24microSV) or as low as 8 microSV ( the "background radiation" we receive from living on the earth = 8 microSV per Day). I personally find Airway / Sinus obstructions & pathology("Incidental findings") in 30% of ALL scans that I take (actually greater in Children along with reported Allergy and facial Biomarkers which relate to Allergy / Airway issues) not including TMJ degenerative or osteoarthritic changes). This correlates with other research findings of Mah, et al and others which found about 25 % "Incidental finding" of Airway/Sinus pathology. I have found 3 patients with cancer that would have gone Undiagnosed and were found early and resolved. Worth while? They think so. I DO NOT take "routine" radiological exams OF any type (2D or 3D) until a complete oral /dental / facial / Med/dental History exam, but if certain facial Biomarkers exist then I May want more complete information than just adequate 2D imaging can give AND at ALARA (As Low AS Reasonably Achievable) doses of 8 - 15 microSV which is LOWER than a digital 2D Pan / Ceph and 3D gives Evidence-Based information beyond what 2D can do. Look a the Chapter on 3D that myself & Dr Mah wrote in Orthodontic Theory & Practice 5th Edition Edited by Robert Vanarsdall, Katherine Vig, et al (Past Editor Graber) by Quintessence.
A radiograph should be recorded only if it is justified. That applies for cephalogram, panoramic radiograph, periapical radiograph as well as for CBCT. The following references may be useful
Al-Okshi A, Lindh C, Salé H, Gunnarsson M, Rohlin M. Effective dose of cone beam CT (CBCT) of the facial skeleton: a systematic review. Br J Radiol. 2015;88(1045):20140658. doi:10.1259/bjr.20140658
Article Effective dose of cone beam CT (CBCT) of the facial skeleton...
https://www.fda.gov/radiation-emitting-products/medical-x-ray-imaging/dental-cone-beam-computed-tomography
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