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 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:

1. Embryology and Genetics
2. Growth and Development
3. Head and Neck Anatomy
4. Histology
5. Oral Physiology and Biochemistry
6. Pathology
7. Research Methodology and Biostatistics
8. Adjunctive Orthodontic Procedures as related to integrated disciplines
9. Biomechanical Principles
10. Cephalometrics and Radiography
11. Clinical Orthodontics (adults and children)
12. Clinical Photography
13. Craniofacial Deformities
14. Dentofacial Orthopedics
15. Infection and Hazard Control
16. Interdisciplinary Comprehensive Care
17. Risk Management
18. Literature Review
19. Principles of Occlusion
20. Orthodontic and Orthopedic Appliance Design
21. Orthodontic Dental Materials
22. Orthodontic Diagnosis and Treatment Planning
23. Orthodontic Technique
24. Radiographic and Imaging Techniques
25. Surgical Orthodontics (Diagnosis, Treatment Planning and Presurgical and Postsurgical Orthodontic Treatment for Orthognathic Surgery)
26. Temporomandibular Disorders
27. Cardiopulmonary Resuscitation

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.

The ABO Written Examination consists of 240 multiple-choice questions and is divided into four (4) modules. Below is a breakdown of the percentage of questions for each specific topic included in the exam:

MODULE 1 - Basic and Applied Biomedical Sciences. Topics include:

Anatomical Sciences	15%
Biochemistry / Physiology / Bone Biology and Histology	19%
Developmental Anatomy / Developmental Disturbances / Genetic Disorders	26%
Growth and Development	25%
Microbiology / Immunology / Infection Control / Pathology	15%

MODULE 2 - Clinical Sciences "A". Topics include:

Occlusion	22%
Temporomandibular Disorders	18%
Radiography / Photography	16%
Cephalometrics / Computer Techniques	28%
Topics below are combined in this percentage	16%
Cardio-Pulmonary Resuscitation / Risk Management / Practice Management / Ethics
Statistics / Research Design / Pharmacology / Pain / Anxiety Control
Preventive Dentistry / Hygiene / Behavioral Science / Patient Management
Speech Pathology / Orthodontic History

MODULE 3 - Clinical Sciences "B". Topics include:

Orthodontic Materials / Physical Principles / Orthodontic Techniques and Appliances	25%
Orthopedics / Biomechanics	21%
Orthodontic Diagnosis / Case Analysis / Treatment Planning	20%
Orthodontic / Surgical Treatment / Periodontal Treatment / Endodontic Treatment	18%
Orthodontic / Restorative Dentistry Treatment / Implants	16%

MODULE 4

Patient Analysis	73%
Anatomical Landmarks of the Skull	16%
Anatomical Landmarks of the Lateral and Frontal Cephalograms	11%

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.

• Journal Articles (Revised July 22, 2008)
• Textbooks        (Revised July 22, 2008)
• Clinical Sections