Background
The ABO Written Examination is a comprehensive exam that
assesses the examinee's knowledge of basic sciences and clinical
concepts. It is administered at computerized testing centers
throughout the United States and Canada. You may petition the board for the opportunity to use a PearsonVUE testing facility outside of the U.S. and Canada. The board will evaluate the security of the test site. If the board concludes the integrity of the examination process can be maintained, permission may be given to test at an overseas facility. Each request will be assessed on an individual basis and the decision of the board is final.
The written examination is available to any educationally
qualified practicing orthodontist who has never taken the
written exam or was unsuccessful on a prior written exam.
Residents in an ADA accredited orthodontic program may take the
written exam in the year of their graduation or if they have
completed 18 months of their program at the time of the
exam. Anyone who has successfully completed the written examination is eligible for the ABO Clinical Examination. There is no time limitation nor expiration date for the written examination.
The written examination consists of 240 multiple-choice
questions and is divided into four (4) modules. Examination
questions are related to the basic sciences, applied biomedical
sciences, orthodontic theory, orthodontic practice, related
dental disciplines and the orthodontic literature. Questions are
developed from various sources by the ABO's Written Examination
Committee. In the past, the committee formulated questions using
the recommended reading list and referencing journals, textbooks
and actual clinical case reports. Now, the process has been
improved in order to keep the examination relevant to
orthodontics as it is practiced today. The ABO has solicited
questions from educators across the country, and will be asking
for submission of questions from residents as well. These
questions are reviewed and refined by the examination committee
and then added to the bank of questions. The goal is to have
thousands of questions in order to write multiple examinations
for the computerization process. To that extent, the ABO has
provided educators (and later, residents) an entry page for question submission on our
website.
It is suggested that candidates review the courses taken
during their advanced orthodontic education, major textbooks,
and current orthodontic literature. The examination is based on
subject areas outlined by the Commission on Dental Accreditation
and includes the following subjects:
- Embryology and Genetics
- Growth and Development
- Head and Neck Anatomy
- Histology
- Oral Physiology and Biochemistry
- Pathology
- Research Methodology and Biostatistics
- Adjunctive Orthodontic Procedures as related to integrated disciplines
- Biomechanical Principles
- Cephalometrics and Radiography
- Clinical Orthodontics (adults and children)
- Clinical Photography
- Craniofacial Deformities
- Dentofacial Orthopedics
- Infection and Hazard Control
- Interdisciplinary Comprehensive Care
- Risk Management
- Literature Review
- Principles of Occlusion
- Orthodontic and Orthopedic Appliance Design
- Orthodontic Dental Materials
- Orthodontic Diagnosis and Treatment Planning
- Orthodontic Technique
- Radiographic and Imaging Techniques
- Surgical Orthodontics (Diagnosis, Treatment Planning and
Presurgical and Postsurgical Orthodontic Treatment for
Orthognathic Surgery)
- Temporomandibular Disorders
- Cardiopulmonary Resuscitation

Test Specifications
The American Board of Orthodontics Written Examination is based on criterion-referenced testing, which is the concept that examinees should be measured against the skill and knowledge represented by each test item. The difficulty of each item for the minimally-competent examinee is the basis for setting the Criterion Standard, one that is represented as an absolute standard on a Benchmark Scale. The Benchmark Scale and Criterion Standard for The American Board of Orthodontics Written Examination were first established in 2003 and updated for 2008 and beyond.
Below is a breakdown of the percentage of questions for each
specific topic included in the written examination:
MODULE 1 (68 Questions) - Basic and Applied Biomedical Sciences. Topics include:
|
Anatomical Sciences
|
14%
|
|
Biochemistry/Physiology
|
6%
|
|
Bone Biology and Histology
|
13%
|
|
Developmental Anatomy/Developmental Disturbances
|
14%
|
|
Genetic Disorders
|
10%
|
|
Growth and Development
|
25%
|
|
Microbiology/Immunology/Infection Control
|
6%
|
|
Pathology
|
12%
|
MODULE 2 (50 Questions) - Clinical Sciences "A". Topics include:
|
Occlusion
|
24%
|
|
Temporomandibular Disorders
|
20%
|
|
Radiography/Photography
|
18%
|
|
Cephalometrics/Computer Techniques
|
30%
|
|
Pharmacology/Pain/Anxiety Control
|
2%
|
|
Preventive Dentistry/Hygiene
|
2%
|
|
Behavioral Science/Patient Management
|
0%
|
|
Speech Pathology
|
2%
|
|
Orthodontic History
|
2%
|
MODULE 3 (67 Questions) - Clinical Sciences "B". Topics include:
|
Orthodontic Materials/Physical Principles
|
8%
|
|
Orthopedics
|
9%
|
|
Orthodontic Diagnosis/Case Analysis/Treatment Planning
|
15%
|
|
Biomechanics
|
13%
|
|
Orthodontic Techniques and Appliances
|
15%
|
|
Orthodontic/Surgical Treatment
|
9%
|
|
Orthodontic/Periodontal Treatment
|
5%
|
|
Orthodontic/Endodontic Treatment
|
5%
|
|
Orthodontic/Restorative Dentistry Treatment
|
7%
|
|
Implants
|
7%
|
|
Cardio-Pulmonary Resuscitation
|
1%
|
|
Risk Management/Practice Management/Ethics
|
3%
|
|
Statistics/Research Design
|
3%
|
MODULE 4 (55 Questions)
|
Patient Analysis
|
73%
|
|
Anatomical Landmarks of the Skull
|
16%
|
|
Anatomical Landmarks of the Lateral and Frontal Cephalograms
|
11%
|

Reading List
The objective of this reading list is to offer the practicing
orthodontist a list of references, which may serve as a source
of knowledge in preparing for board certification. This reading
list includes papers of historical as well as scientific
interest. It is intended to give the orthodontist a broad
perspective of the changing world of orthodontic theory and
practice. Several articles by ABO directors are also included so
that the candidates may have some insight into their background
and current interests. It should be clearly understood that a
bibliography, such as this, is not all encompassing and does not
remain static. It will be continuously subject to additions and
deletions. Current literature and textbooks on orthodontics may
be studied in addition to the suggested references.
The American Board of Orthodontics does not consider any of
the texts and/or articles to contain the indisputable answer to
any questions within the field of orthodontics.
