General dentistry. In the United States, individuals can enter practice in dentistry with a first professional D.D.S. or D.M.D. degree. In addition to providing preventive care, dentists may restore damaged or missing teeth and treat diseases of the mouth. Advanced postdoctoral residency programs in general dentistry lasting twelve or twenty-four months are also available, providing exposure to a variety of practice areas. These programs are very competitive and difficult for internationally educated dentists to enter.

Endodontics. Endodontists diagnose and treat diseases and injuries of the inner tooth structure. Residency programs in this specialty typically last between twenty-four and thirty-six months.

Public health. Public health dentists promote dental health through organized efforts to educate and inform the public. Residency programs typically last twelve to twenty-four months.

Oral and maxillofacial pathology. Oral pathologists diagnose diseases of the mouth through laboratory procedures including clinical, microscopic, radiographic, and biochemical examinations. Residency programs typically last thirty-six months.

Oral and maxillofacial radiology. Oral and maxillofacial radiologists use imaging and associated technologies in the diagnosis and management of diseases affecting the mouth, jaws, and related areas.   Programs last twenty-four to thirty-six months.

Oral and maxillofacial surgery. Oral and maxillofacial surgeons extract teeth and repair defects of the mouth through surgery.  Programs vary in length from four to six years and are all residency programs; some award the Doctor of Medicine (M.D.) degree.

Orthodontics and dentofacial orthopedics. Orthodontists prescribe and fit braces to correct abnormalities in teeth and in jaw alignment.  Most residency programs last twenty-four to thirty-six months.

Pediatric dentistry. Pediatric dentists provide dental care for children, adolescents, and disabled people with special dental care needs.  Residency programs typically last twenty-four to thirty-six months.

Periodontics. Periodontists treat diseases of the gums, the mouth’s mucous membranes, and other tissue supporting the teeth.  Most residency programs last thirty-six months.

Prosthodontics. Prosthodontists replace lost teeth, designing and fitting bridgework, dentures, and implants. Residency program length varies between twelve and thirty-six months.