NBDE Cheat Sheet 2026

The 30 highest-yield NBDE facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. The maximum safe dose of lidocaine WITH epinephrine in a healthy adult is approximately: → 7 mg/kg (not to exceed 500 mg)
2. Compared to a permanent molar, a primary molar pulp is characterized by: → More prominent pulp horns and thinner dentinal walls
3. Informed refusal occurs when a patient declines recommended treatment. The dentist should: → Document the refusal and the risks explained in the patient's record
4. Which cusp of the maxillary first molar is the smallest and least functional? → Cusp of Carabelli
5. Which of the following best describes the 'critical pH' for enamel demineralization? → pH 5.5
6. Which of the following salivary gland tumors is most likely to undergo malignant transformation? → Pleomorphic adenoma
7. Respondeat superior is a legal doctrine that holds: → Employers liable for the negligent acts of employees acting within the scope of employment
8. Which of the following is the most common type of occlusion in a normal dentition? → Class I
9. The mucogingival junction can be identified by: → A color change from pink keratinized gingiva to red alveolar mucosa
10. Website for drug administration includes: → Intramuscular, oral, transdermal, intravenously
11. The 'double cortical outline' sign on a panoramic radiograph of the mandibular canal is associated with: → Inferior alveolar nerve schwannoma
12. Which radiographic finding is MOST characteristic of a periapical cyst versus a periapical granuloma? → Periapical cysts tend to be larger with a well-defined corticated border
13. Koilocytes found on cytologic smear are pathognomonic for infection with: → Human papillomavirus
14. Which probe is specifically designed for detecting furcation involvement in multirooted teeth? → Nabers probe
15. A patient develops paresthesia of the lower lip after root canal treatment of a mandibular second molar. What is the most likely cause? → Over-instrumentation beyond the apex compressing the inferior alveolar nerve
16. Composite resin polymerization shrinkage is most effectively reduced by: → Incremental placement technique
17. A patient with recurrent herpetic labialis is under stress. Which statement best describes the pathogenesis of the recurrence? → HSV-1 reactivates from latency in the trigeminal ganglion
18. Enamel matrix derivative (Emdogain) promotes periodontal regeneration primarily by mimicking which developmental process? → Hertwig's epithelial root sheath signaling during cementogenesis
19. Which clinical scenario represents the strongest relative contraindication to vasoconstrictors in local anesthetics? → Severe uncontrolled hypertension
20. Which of the following best describes the 'C-factor' in composite resin placement? → Ratio of bonded to unbonded surfaces in a cavity
21. Which local anesthetic has the longest duration of action for pulpal anesthesia? → Bupivacaine 0.5%
22. Which cavity preparation principle was modified by GV Black's successors to adopt a more conservative 'extension for prevention' approach? → Outline form (extension for prevention)
23. A patient presents with a tooth that tests vital with cold but has a periapical radiolucency. What is the most likely diagnosis? → Non-odontogenic lesion or anatomical landmark
24. On a periapical radiograph, the lamina dura appears as a thin radiopaque line because it represents: → Cortical bone lining the alveolar socket
25. During glycolysis, glucose is first phosphorylated to glucose-6-phosphate by which enzyme? → Hexokinase
26. Which landmark on the maxillary central incisor crown is used to distinguish it from the lateral incisor? → Sharper mesioincisal angle compared to the distoincisal angle
27. Which landmark on the mandible serves as the attachment site for the medial pterygoid muscle? → Medial surface of ramus and angle
28. Ketorolac is preferred over other NSAIDs for short-term postoperative pain because it: → Can be administered parenterally for potent analgesia
29. Which microscopic zone of necrotizing ulcerative gingivitis does the necrotic zone occur? → Zone 3
30. Dry socket (alveolar osteitis) typically becomes symptomatic within how many days after extraction? → 3–5 days