JCNDE (Joint Commission on National Dental Examinations), ADA
NBDHE
National Board Dental Hygiene Examination
The national board exam dental hygiene students must pass as a prerequisite for state dental hygiene licensure. It combines discipline-based questions with patient case-based items covering the full scope of dental hygiene practice.
What's on the exam
NBDHE Test Specifications (2026 Candidate Guide); updated specifications take effect November 1, 2026 (discipline-based items rebalance to 56 scientific basis / 124 clinical services / 20 research and community health)
Scientific Basis for Dental Hygiene Practice
~31% of discipline-based itemsAnatomic sciences (head/neck, dental anatomy, histology, embryology) · Physiology · Biochemistry and nutrition · Microbiology and immunology · General and oral pathology · Pharmacology
Provision of Clinical Dental Hygiene Services
~58% of discipline-based itemsAssessing patient characteristics · Obtaining and interpreting radiographs · Planning and managing dental hygiene care · Periodontal instrumentation and debridement · Prevention and management of emergencies · Patient education and oral health promotion
Community Health and Research Principles
~12% of discipline-based itemsPromoting health in the community · Participating in community programs · Biostatistics and research methods · Epidemiology · Evidence-based decision making
Frequently asked questions
How much does the NBDHE cost?
The NBDHE costs $600. Examination fee; additional $435 processing fee for students and non-CODA graduates.
How long is the NBDHE and how many questions does it have?
350 items total (200 discipline-based, 150 case-based) — Full-day exam: 7 hours 30 minutes of testing across two sessions (9 hours total including tutorial and breaks).
What do you need to pass the NBDHE?
Scale score of 75 (pass/fail).
Can you retake the NBDHE?
Minimum 60 days between attempts; maximum 4 attempts in any 12-month period; must pass within 5 years or 5 attempts, after which testing is limited to once every 6 months.
What is the best way to study for the NBDHE?
Start from the official outline and your primary study materials: the exam is weighted by domain (Scientific Basis for Dental Hygiene Practice ~31% of discipline-based items, Provision of Clinical Dental Hygiene Services ~58% of discipline-based items, Community Health and Research Principles ~12% of discipline-based items). Once you've learned the material, spaced-repetition flashcards organized by those domains are an efficient way to retain it and refresh it before test day.
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