NBDE Part I (National Board Dental Examination Part I (legacy, replaced by INBDE)) — Free Online Mock Test

Historical US dental board (last administered 2020 — kept for licensure equivalency abroad). 400 MCQ over 1.5 days covering Anatomic Sciences, Biochemistry/Physiology, Microbiology/Pathology, Dental Anatomy & Occlusion. Pass at 75 scaled. · Official language: English.

Elite United States Medical Licensing 400 questions 960 min 50 distinct variants
Start free practice test →

NBDE Part I exam at a glance

400
Questions
960
Minutes total
4
Sections
50
Variants

NBDE Part I section breakdown

The NBDE Part I mock test on Wrexa Edge replicates the real exam's section structure — same names, same question count per section, same time limits. Inter-section breaks are enforced.

NBDE Part I scoring & marking scheme

+1
Per correct answer
0
Per wrong answer
0
Per blank / skipped
0–100
Scaled score range

Strategy: NBDE Part I has no negative marking. Attempt every question — blank answers cost you potential marks but cannot pull your score down.

Scale: NBDE Part I (pass scaled 75).

How NBDE Part I is conducted

NBDE Part I time strategy

With 400 questions in 960 minutes, you have about 144 seconds per question on average. Successful candidates aim for the following pacing on each section:

Wrexa Edge's analytics show your actual time-per-question after every mock so you can spot which sections you're losing time on.

NBDE Part I topics covered

Across the 50 Wrexa Edge variants of NBDE Part I, the following topics appear most often (sample distribution from one variant):

Anatomic Sciences (100 Q)

Biochemistry & Physiology (100 Q)

Microbiology & Pathology (100 Q)

Dental Anatomy & Occlusion (100 Q)

Sample NBDE Part I questions

A preview of real practice questions from the Wrexa Edge NBDE Part I bank — the same style, phrasing and difficulty you'll face on test day. Full solutions unlock free inside the mock.

Anatomic Sciences (100 Q) · Anatomy — Notation
Q1. Tooth notation under the Universal Numbering System (US): tooth #8 is the:
Why: Correct answer: D — Permanent maxillary right central incisor. Topic: Anatomy — Notation.
Biochemistry & Physiology (100 Q) · Chemistry — Fundamentals
Q2. Chemical formula of methane:
Why: Correct answer: D — CH₄. Topic: Chemistry — Fundamentals.
Microbiology & Pathology (100 Q) · Anatomy — Notation
Q3. Tooth notation under the Universal Numbering System (US): tooth #8 is the:
Why: Correct answer: D — Permanent maxillary right central incisor. Topic: Anatomy — Notation.
Dental Anatomy & Occlusion (100 Q) · Anatomy — Notation
Q4. Tooth notation under the Universal Numbering System (US): tooth #8 is the:
Why: Correct answer: D — Permanent maxillary right central incisor. Topic: Anatomy — Notation.
Anatomic Sciences (100 Q) · Anatomy — Roots
Q5. How many roots does a normal maxillary first molar have?
Why: Correct answer: A — Three — two buccal (MB, DB) and one palatal. Topic: Anatomy — Roots.
Biochemistry & Physiology (100 Q) · Chemistry — Fundamentals
Q6. Strongest reducing agent among alkali metals (aqueous):
Why: Correct answer: A — Li. Topic: Chemistry — Fundamentals.

These are a handful of the 20000 unique NBDE Part I questions across all 50 Wrexa Edge variants — start a free mock to attempt the full set with instant scoring.

NBDE Part I difficulty calibration

Elite tier. Elite-tier: among the toughest exams in its category. Most successful candidates prepare for 6-12+ months.

Historical US dental board (last administered 2020 — kept for licensure equivalency abroad). 400 MCQ over 1.5 days covering Anatomic Sciences, Biochemistry/Physiology, Microbiology/Pathology, Dental Anatomy & Occlusion. Pass at 75 scaled. · Official language: English.

Verified content — Wrexa Edge's NBDE Part I bank has been deeply curated with real exam-aligned content (estimated 100% syllabus coverage).

How Wrexa Edge prepares you for NBDE Part I

NBDE Part I study plan

A phase-by-phase roadmap from your first concept to test-ready. Stretch or compress each phase to fit the time you have before your attempt.

1 Phase 1 — Learn the syllabus Weeks 1–4
  • Work through every section — Anatomic Sciences (100 Q), Biochemistry & Physiology (100 Q), Microbiology & Pathology (100 Q), Dental Anatomy & Occlusion (100 Q) — from your core study material
  • Make short notes and a formula/fact sheet you can revise quickly
  • Attempt topic questions right after finishing each area
2 Phase 2 — Practice & sectionals Weeks 5–8
  • Solve previous-year and practice questions section by section
  • Time yourself on Anatomic Sciences (100 Q) and your weakest areas
  • Keep an error log and revisit every mistake weekly
3 Phase 3 — Full-length mocks Weeks 9–12
  • Take full-length NBDE Part I mocks in the real test interface
  • Analyse accuracy, time per question and silly mistakes after each mock
  • Revise from notes and re-attempt only weak-topic questions

Where NBDE Part I can take you

A strong NBDE Part I result opens up these careers and higher-study paths:

Frequently asked questions

What is the NBDE Part I exam pattern?
National Board Dental Examination Part I (legacy, replaced by INBDE) contains 400 questions across 4 sections: Anatomic Sciences (100 Q), Biochemistry & Physiology (100 Q), Microbiology & Pathology (100 Q), Dental Anatomy & Occlusion (100 Q). Total duration is 960 minutes (about 144 seconds per question).
Does NBDE Part I have negative marking?
No — NBDE Part I has no negative marking. Each correct answer is worth 1 mark, so attempt every question.
How is NBDE Part I scored?
Scaled score range: 0 to 100. NBDE Part I (pass scaled 75).
How can I practise NBDE Part I online for free?
Wrexa Edge gives you 10 free full-length NBDE Part I mock tests — with instant scoring, detailed explanations and analytics — plus 40 more with Pro. Start practising in under a minute, no card required.
What is the difficulty level of NBDE Part I?
NBDE Part I is rated Elite difficulty on Wrexa Edge. Elite-tier: among the toughest exams in its category. Most successful candidates prepare for 6-12+ months. Historical US dental board (last administered 2020 — kept for licensure equivalency abroad). 400 MCQ over 1.5 days covering Anatomic Sciences, Biochemistry/Physiology, Microbiology/Pathology, Dental Anatomy & Occlusion. Pass at 75 scaled. · Official language: English.
How long is the NBDE Part I exam?
NBDE Part I runs for 960 minutes total across 4 sections. On Wrexa Edge the timer is enforced exactly as on the real exam — including mandatory inter-section breaks.
What topics are covered in NBDE Part I?
NBDE Part I is split into: Anatomic Sciences (100 Q), Biochemistry & Physiology (100 Q), Microbiology & Pathology (100 Q), Dental Anatomy & Occlusion (100 Q). Each section is timed and weighted separately. Historical US dental board (last administered 2020 — kept for licensure equivalency abroad). 400 MCQ over 1.5 days covering Anatomic Sciences, Biochemistry/Physiology, Microbiology/Pathology, Dental Anatomy & Occlusion. Pass at 75 scaled. · Official language: English.
What tools or aids are allowed during NBDE Part I?
No special tools are required.
Is the NBDE Part I test adaptive?
No — NBDE Part I is a fixed-form (linear) test. Every candidate sees the same number of questions per section.
How many NBDE Part I mock tests does Wrexa Edge offer?
Wrexa Edge generates 50 distinct NBDE Part I variants — each with different question content, not just shuffled options — the first 10 free for everyone and 40 more with Pro. That's 20000 unique practice questions in the real test-day interface.
Is there a free NBDE Part I test series 2026?
Yes. The Wrexa Edge NBDE Part I test series for 2026 gives you 10 free full-length mock tests (50 in total) plus subject-wise and topic-wise tests — instant scoring and detailed analysis, no card required.
Are NBDE Part I previous year question–style papers included?
Every NBDE Part I mock is modelled on the official exam pattern and the style of previous years' papers — the same 400-question structure, sections and marking — so your practice mirrors the real paper you'll sit.
Which is the best free NBDE Part I mock test online?
Wrexa Edge's NBDE Part I mock test replicates the real exam interface, timing and marking scheme, with instant score, section-wise analysis and 50 fresh variants — a strong free choice for 2026 preparation.
Can I take the NBDE Part I mock test on mobile?
Yes. NBDE Part I mock tests run in any browser on mobile, tablet or desktop — no app or download needed. Start on your phone and your progress and analytics sync when you sign in.
What is the NBDE Part I syllabus?
The NBDE Part I syllabus maps to its 4 sections: Anatomic Sciences (100 Q), Biochemistry & Physiology (100 Q), Microbiology & Pathology (100 Q), Dental Anatomy & Occlusion (100 Q). Wrexa Edge's mock tests cover the complete syllabus topic by topic — see the topics-covered breakdown above — so you practise every area at real exam difficulty.
What is the eligibility for NBDE Part I?
Eligibility for NBDE Part I — age, qualification and number of attempts — is set by the official conducting body and can change each cycle, so always confirm the current official notification before applying. Wrexa Edge focuses on realistic NBDE Part I practice: 10 free full-length mocks in the exact exam pattern, ready whenever you are.
When is the NBDE Part I exam and how should I prepare?
Official NBDE Part I exam dates are announced by the conducting body for each cycle — check the latest notification for the current schedule. To be ready, follow a phased study plan and take full-length timed mocks; Wrexa Edge gives you 10 free NBDE Part I mocks with instant scoring so you can track your readiness week by week.

Related exams & practice tests

Candidates preparing for NBDE Part I also practise these on Wrexa Edge:

Browse more: All Medical Licensing exams →  ·  All United States exams →  ·  Full exam catalog →

Ready to ace NBDE Part I?

Join thousands of candidates practising on Wrexa Edge. Free signup, 50 variants per exam, instant scoring.

Start practising free →