In Response to Letter to the Editor

Dear Shahista Parveen

Greetings from the Editorial office of the JIOS. We are writing to you regarding your article “Awareness and practice of ethics and guidelines with cone-beam computed tomography prescription in orthodontics” in January-March (2019) issue. We have received a communication, for certain clarifications regarding your article. Kindly draft an author’s response for the same.

Following are the points raised:

In the “Principle of Justice” section of the article, the authors have mentioned that exposing a patient to posttreatment cone beam computed tomography (CBCT) for acceptance of the paper in journals is not justified. Kindly cite a reference in support of this claim.

In the “Research Ethics” section the authors have mentioned that it is unethical to prescribe CBCT for prospective research to produce data for future research projects. It would be helpful to readers if the authors mention on how this unethical act can be curbed?

The authors should mention why strict regulation should be made for accumulating routine CBCT imaging and later storing it as a retrospective database. Storing the data as a retrospective database does not increase the collective effective dose for patients but instead eliminates the need for taking fresh CBCT scans (when it is indicated) for doing prospective research, and hence, unnecessary exposure to the patients for research purpose will greatly be minimized.

The authors mention that CBCT studies should not be repeated. But it is not clear in the article what regulations can be enacted to prevent this repetition.

In the “principles of autonomy” section, the authors have mentioned about stochastic effects of radiation associated with CBCT. Stochastic effects such as cancer can occur with even low exposures and with no evidence of a threshold dose. This implies that the risks associated with stochastic effects are not limited only to CBCT but even can occur with radiation associated with intraoral periapical radiograph, cephalometric radiograph, or panoramic radiograph.

Author’s Response

Dear Editor,

Thank you for the queries and interest shown in our article titled “Awareness and practice of ethics and guidelines with cone-beam computed tomography prescription in orthodontics” which appeared in JIOS January-March (2019) issue.

The American Academy of Maxillofacial Radiology in the year 2013 came out with a position statement at the request of the American Association of Orthodontists. This position paper titled “Clinical recommendation regarding use of CBCT in orthodontics” dealt with all aspects of the use of CBCT in orthodontics ¹ . In February 2015, the American Journal of Orthodontics and Dentofacial Orthopedics, in their centennial special article, titled “Appropriate use of ionizing radiation in orthodontic practice and research” by Ahmed A. Abdelkarim recommended the image gently campaign protocol to be followed ² . When he discussed ethical issues he stated: “It is unethical to routinely prescribe pretreatment posttreatment CBCT for prospective research to produce data for future research projects, as this would increase the collective effective dose for orthodontic patients and may ultimately cause harm to some.”

Although it is believed there is no threshold radiation dose below which stochastic effect will not occur, there may be “chance” stochastic effect where the magnitude of risk, though not the severity of the effect, is proportional to the radiation dose ³ . The probabilistic nature of stochastic effect makes the distinction between “safe” and “dangerous” exposure to radiation impossible. The radiosensitivity of tissues is taken into account using an effective dose which is a more relevant quantity to estimate stochastic effect. The effective dose is calculated by taking the equivalent dose and multiplying it with tissue-weighting factor.

“Image Gently” campaign was a campaign of the alliance for radiation safety in pediatric imaging initiated by a group of pediatric radiologists to promote radiation safety in the imaging of children ⁴ . This alliance is a coalition of health care organizations dedicated to provide safe and high-quality pediatric imaging worldwide. Later came the “Image Gently in Dentistry” campaign whose primary objective is to raise awareness and use CBCT only when lower dose imaging techniques cannot answer a clinical question ⁵ . Although CBCT has the potential to assess and resolve unresolved complex cases and questions in orthodontics, it is important to fully justify CBCT and increase effort to limit radiation exposure.

Recommendation

Although many guidelines exist, awareness, knowledge, and practice are lacking. Therefore, we feel that the following steps may be taken:

Formulating of CBCT guidelines for orthodontists in India.

Generating awareness of the existing guidelines worldwide.

Making CBCT guidelines part of the curriculum.

Having awareness campaigns similar to the Image Gently campaign.

Following SEDENTEXCT guidelines where it is mandatory to record the justification process for CBCT prescription and reporting and documenting complete interpretation of CBCT.

Recommending special training in interpretation and CBCT guidelines for orthodontists.

Forming a registry for approval of all CBCT studies to avoid repetition.

Forming a repository for all CBCT studies to avoid duplication.

Forming a special committee comprising orthodontists, radiologists, and legal persons to assist orthodontists in taking decisions regarding CBCT.

Monitoring CBCT centers and institution specially to prevent overuse, misuse, and self-referral when orthodontist is an owner.

Thanking You.

Regards,