Question 1
Four patients are scheduled for scaling and root planing. Under the 2021 AHA scientific statement, which patient should receive antibiotic prophylaxis to prevent infective endocarditis?
Dental hygiene board exam prep
NBDHE format: sessions, questions and timing
The exam is 350 multiple-choice questions in two sessions: 200 discipline-based questions in 3 hours 30 minutes, then 150 questions on 12 to 15 patient cases in 4 hours. With the optional tutorial, breaks and survey, the appointment is 9 hours.
| Session One | 200 discipline-based questions in 3 hours 30 minutes, with an optional 15-minute break |
|---|---|
| Session Two | 150 case-based questions on 12 to 15 patient cases in 4 hours, with an optional 15-minute break |
| Between sessions | An optional 30-minute break |
| Answer options | 3 to 5 per question, one correct or best answer; no penalty for guessing |
| Whole appointment | 9 hours, with the optional 15-minute tutorial and 15-minute survey |
Session One: the discipline-based component
From November 1, 2026 the 200 questions follow updated test specifications: Scientific Basis for Dental Hygiene Practice (56), Provision of Clinical Dental Hygiene Services (124) and Research Principles and Community Health (20). Before that date the split is 61, 115 and 24. The JCNDE says the update is not expected to substantially alter preparation; candidates should use the specifications for their test date.
- Scientific basis: head and neck and dental anatomy, histology and embryology, physiology, biochemistry and nutrition, microbiology and immunology, general and oral pathology, and pharmacology, now including local anesthesia.
- Clinical services: patient assessment, dental radiography, care planning, periodontal disease management, preventive agents, supportive treatment services and professional responsibility.
- Research and community health: reading studies and statistics, and planning and evaluating community programs. These questions often come as testlets: a community profile followed by several questions.
Session Two: patient cases
Each case gives a patient box (history, vital signs, medications, dental history and findings) with dental charts, radiographs and clinical photographs, followed by about 10 questions. Patients include geriatric, adult periodontal, pediatric, special needs and medically compromised patients. If the box leaves something out, treat it as unknown: with no allergies listed, assume none are known.
The questions cover assessment, radiography, care planning, periodontal management, preventive agents, supportive treatment and professional responsibility, applied to that patient.
How the questions are written
The guide shows three forms: a completion stem, a direct question, and a negative item with the key word in capitals ("Each of the following ... EXCEPT one. Which is the EXCEPTION?"). Teeth are named with the Universal system, 1 to 32 and A to T. Some questions are unscored trial items that look the same as the rest.
Try 2 questions
Question 2
Plaque scores in a large group are normally distributed with a mean of 60 and a standard deviation of 8. About what percentage of the group scored between 52 and 68?
Next step
Questions people ask
How many questions are on the NBDHE?
350 multiple-choice questions: 200 discipline-based questions in Session One and 150 case-based questions in Session Two.
How long is the NBDHE?
7 hours 30 minutes of testing time: 3 hours 30 minutes for Session One and 4 hours for Session Two. With the optional tutorial, breaks and survey the appointment is 9 hours.
What changes in November 2026?
Updated test specifications take effect on November 1, 2026. Session One becomes 56 scientific basis, 124 clinical services and 20 research and community health questions. The JCNDE says the changes are not expected to substantially alter preparation.