Zoe Najim, Dental Assistant Test Expert


Zoe Najim is curriculum specialist for the Colorado School of Dental Assisting, which she founded in 2001. She also manages the National School of Dental Assisting, located in Washington, California, Ohio, Texas and Arizona. She has worked for dental practices and has a master's degree in education.

How did you get interested in the career of dental assisting?
I was a dental assistant after I finished my Master’s in Education for the summer. The job was so interesting and fun that I was pleasantly surprised. For a position that really did not have any pre-requisites, it is a great and respected job with a decent wage. But I was trained on the job, which was very stressful and inefficient. I thought if I had some background and if I had been taught the procedures in a stress-free and empowering environment, I would have enjoyed the experience a lot more.

Does one need special schooling or training to work as a dental assistant?
Legally one does not need special training to be a basic dental assistant although it is common for some states to require certain courses for radiology certification (taking x-rays). And some states do require certain course work and tests, such as the DANB RHS exam (radiation health and safety), or state board approved exams in order to be an RDA or registered dental assistant.

The Dental Assisting National Board (DANB) gives a certifying exam for Dental Assistants, called the Certified Dental Assistant (CDA) Exam. Does one need to be certified to work as a dental assistant?
No, one does not need to be a certified dental assistant (CDA) to work as a dental assistant, however, some states do recognize the CDA certification for allowing dental assistants to practice expanded functions in dental assisting. Basic dental assisting, including tasks such as chair-side assisting, disinfection and sterilization and taking x-rays, can be performed without the CDA certification in almost all states. A few states require the CDA certification or a state dental board course and exam to certify assistants to perform expanded functions, such as taking impression, placing sealants, performing a coronal polish, etc. Several states employ one or more sections of the Certified Dental Assistant exam, such as the Radiation Health and Safety (RHS) exam, or the Infection Control Exam (ICE) as requirements for either taking x-rays in the state, becoming a registered dental assistant or in order to perform expanded functions. Still other states only have training and/or exam requirements for taking x-rays (radiology), and some states have no requirements for any education or exam to work as dental assistants. Some states, such as California and Texas have their own state board-approved courses and exams for certifying dental assistants in specific tasks, such as x-rays or expanded duties.

What is the value of becoming a certified dental assistant?
The CDA certification is recognized in many states and can aid dental assistants at becoming either RDAs or able to perform expanded functions in states with hierarchical regulations, and without their own board-approved certifying courses. Some states recognize the CDA certification for performing expanded duties in dental assisting. This increases the employability with dental offices looking for expanded function assistants.

The DANB offers certification as an assistant for orthodontics, the Certified Orthodontic Assistant (COA) exam. Does one have to get the certification to work in the field of orthodontics?
Again, this is state by state. Some states do not have any regulations for orthodontic assistants, and some states do. A quick look at the DANB state-specific page can tell a prospective dental assistant what the regulations are for assistants and ortho assistants in their state. For the states with regulations for ortho assisting, the COA credential does satisfy the state’s requirements. But not all states have these requirements.

What is the value of becoming a certified assistant in orthodontics?
Orthodontic assisting is a huge sub-field of dental assisting with much demand. Orthodontists usually employ many assistants and the assistants do many skilled tasks. Having the COA certification from the DANB is one way to show an employer that the assistant is skilled, interested and learned in these tasks.

How do students of dental assisting study for the CDA and COA exams? Are there prep courses available?
The DANB has study materials. Also it is possible to get a list of textbooks that are recommended to purchase online and study. A short dental assisting program can act as a refresher for assistants who have not worked recently or who were enrolled in a dental assisting program a long time ago. Try the book Dental Radiography: Principles and Techniques, by Harring, I. and Howerton, L.J. www.us.elsevierhealth.com is a good preparation for the RHS exam. A general textbook that we use for instruction, which is a good prep book for the individual components or for the CDA exam, is Essentials of Dental Assisting, by Robinson and Bird. The DANB website’s reference page also has a comprehensive list: http://www.danb.org/PDFs/ExamReferenceMaterials.pdf

Do you have any suggestions on how to prepare for the exams?
I think the DANB study materials and studying the textbooks are good ideas. Studying and memorizing concepts and terminology, as well as procedures and indications for those procedures will be necessary. Practice exams, available in some schools are also good ways to determine if the studying is yielding the proper results.

Is there anything else that people should know about becoming a certified dental assistant?
It is important to check with the regulations in specific states in order to know whether the CDA certification is necessary or even recognized in your state. In some states, there are no requirements for education among dental assistants, except maybe opinions held personally of the dentist who is hiring. The employer is usually more interested in the level, speed and general aptitude of certain skills and tasks of the dental assistant, rather than their education and certifications. But some states do require certifications in order to legally perform some tasks, and in those states, the requirements can sometimes be satisfied with the CDA certification.

For more on dental assisting, read our Dental Assistant Test Guide. To find a test or test preparation materials, visit our Dental Assistant Test Directory.


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