6 NBDE I Sample Test

NATIONAL BOARD PART I SAMPLE TEST ITEMS The following 40 test items are representative of the four disciplines in the National Board Part I Dental Examinations -Anatomic Sciences, Biochemistry-Physiology, Biochemistry-Physiology, Microbiology-Pathology Microbiology-Pathology and Dental Anatomy and Occlusion. You may wish to read the test items and record record your choice of an answer for each item before before you check the answer key on page 40. There is only one correct or best response for a test test item. On an actual test it is better to to guess than leave an answer blank. There is no penalty for guessing wrong. ANATOMIC SCIENCES 1.

A. B. C. D. E.

2.

5.

Which of the following blood elements is a fragment of megakaryocytic cytoplasm? Platelet Normoblast Erythrocyte Promyelocyte Proerythroblast

A. B. C. D. E.

6.

Which of the following cells is  MOST likely to contain an abundant amount of roughsurfaced endoplasmic reticulum? A. B. C. D. E.

Pericyte Macrophage Osteoblast Endothelial cell Lymphocyte

Which of the following is the prime muscle in retracting and elevating the mandible? A. B. C. D. E.

Masseter Digastric Mylohyoid Temporalis Lateral pterygoid

4.

A patient has a profound disturbance in equilibrium, alterations of gait (ataxia), and intention tremor. tremor. This patient patient  MOST likely has a massive lesion that involves which of  the following? A. B. C. D. E.

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enamel. dentin. cementum. true denticle.

Which of the following is the first formed portion of the dentin? A. B. C. D. E.

Amygdala Cerebellum Cerebral cortex Caudate nucleus Lenticular nucleus

arterioles. capillaries. vasa vasorum. metarterioles. glomus.

The one calcified structure of a tooth incapable of continued growth after eruption is the A. B. C. D.

8.

ileum. stomach. appendix. esophagus. urinary bladder.

Vessels supplying blood to the walls of large arteries are collectively known as A. B. C. D. E.

7. 3.

The muscularis externa contains some striated muscle in the

Circumpulpal Intertubular Transparent Reparative Mantle

9.

10.

Which of the following represents the posterior boundary of the oral cavity and the anterior boundary of the fauces? A. B. C. D. E.

Tonsil Soft palate Dorsum of the tongue Palatopharyngeal arch Palatoglossal arch

Each of the following PDL fiber groups is found in association with a central incisor  EXCEPT  one. Which one is this  EXCEPTION ? A. B. C. D. E.

Apical Oblique Horizontal Alveolar crest Interradicular

BIOCHEMISTRY-PHYSIOLOGY 1.

Hypoglycemia results from the excessive secretion of  A. B. C. D. E.

2.

4.

glucose. insulin. glucagon. cyclic-AMP. epinephrine.

A. B. C. D. E.

Vitamin A Niacin Thiamine Vitamin D Vitamin E

The fluoride concentration in body fluids is regulated principally by which of the following? 5. A. B. C. D. E.

Hormonal action Bone resorption and kidney tubular secretion Simple skeletal exchange and resorption of bone Skeletal uptake and soft tissue deposition Skeletal uptake and renal excretion

Which of the following amino acids is a precursor for epinephrine? A. B. C. D. E.

Gout is a disease of purine overproduction. In this disease, joints develop crystals of  A. B. C. D. E.

6. 3.

Which of the following vitamins is  MOST  likely to be involved with bone loss in the elderly?

Valine Leucine Tyrosine Cysteine Tryptophan

The MOST susceptible sites in the nervous system for the effects of acute ishemic anoxia are the A. B. C. D.

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urea. adenine. guanine. hypoxanthine. sodium urate.

motor end-plates. sensory receptors. synapses in autonomic ganglia. synapses in the central nervous s system.

7.

9.

An enzyme increases the rate of a biochemical reaction by A. B. C. D. E.

decreasing substrate concentration. decreasing activation energy. increasing Km. increasing Keq. increasing released free energy.

A. B. C. D. E.

10. 8.

Excluding the effect of drugs, apnea occurring after hyperventilation of an anesthetized patient results from A. B. C. D. E.

Anemia is frequently associated with a deficiency of 

Each of the following is an important function of saliva  EXCEPT  one. Which one is this  EXCEPTION? A. B. C. D. E.

decreased demand for oxygen. increased cerebral blood flow. decreased carbon dioxide tension. increased hydrogen ion concentration. decreased oxygenation of carotid bodies.

vitamins A and D. vitamins C and D. vitamins E and K. vitamin B12 and folic acid. thiamine, riboflavin, and niacin.

Provides buffering action Facilitates deglutition Initiates protein digestion Prevents demineralization Enhances flavor

MICROBIOLOGY-PATHOLOGY

1.

A. B. C. D. E.

2.

3.

What are the "sulfur granules" found in actinomycotic lesions? Uric acid crystals Coagulated pus cells Calcified necrotic tisue Colonies of the infecting organism Agglutinated platelets and lymphocytes

A. B. C. D. E.

4.

Which organ is the MOST susceptible to infarction due to systemic arterial thromboembolism? A. B. C. D. E.

The aerosol produced during operative dental procedures is likely to contain a predominance of which of the following?

Brain Heart Liver Colon Lung

Ten days after being hospitalized for a large, incapacitating myocardial infarct, a 50-yearold man suddenly develops a paralysis of the right side of his body. Which of the following  BEST explains the damage to his brain? A. B. C. D. E.

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Yeasts and spirochetes Spirochetes and rod forms Spirochetes and rickettsiae Gram-positive rods and cocci Gram-negative rod forms and spirochetes

Rupture of a congenital aneurysm of  the circle of Willis Brain abscess from necrosis of  myocardium Formation of a bacterial embolus from the pulmonic valve Embolization of a mural thrombus from the right ventricle Detachment of a mural thrombus from the left ventricle

5.

A. B. C. D. E.

6.

Fluoride affects the metabolism of oral bacteria by inhibiting an enzyme in which of the following pathways?

Anthrax Botulism Chancroid Bacteroidosis Salmonellosis septicemia

A. B. C. D. D.

Which of the following organs possesses the greatest capacity for regeneration? A. B. C. D. E.

7.

8.

Which of the following conditions represents an intoxication rather than an infection?

9.

Glycolytic Folic acid Citric acid Aspartate biosynthetic Extracellular polysaccharide

Which component of the HIV virus is inhibited by AZT treatment?

Lung Liver Heart Brain Kidney

A. B. C. D. E.

gP120 ss RNA genome ds DNA genome Viral receptor Reverse transcriptase

In contrast to an exudate, a transudate has a A. B. C. D. E.

10. Which of the following represents the virus  MOST likely to pass the placenta and produce congenital defects in the fetus?

cloudy appearance. higher specific gravity. lower protein concentration. larger number of erythrocytes. characteristic cellular component.

A. B. C. D. E.

Mumps Rubella Rubeola Variola Varicella

DENTAL ANATOMY AND OCCLUSION

1.

2.

Which of the following newly erupted teeth is  MOST likely to exhibit only one pulp horn? A. B. C. D. E.

#31 #28 #19 #15 #5

Which of the following maxillary anterior teeth has a mesiodistal crown width that is greater than the incisocervical height? A. B. C. D. E.

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Primary central incisor Primary lateral incisor Central incisor Lateral incisor Canine

3.

How many pulp horns are usually present in a typical primary mandibular first molar? A. B. C. D. E.

4.

7.

1 2 3 4 5

A. B. C. D.

Considering root morphology, which of the following teeth MOST readily lend themselves to rotation during extraction? A. B. C. D. E.

The anatomy of the mesial surface of which of the following teeth is  MOST likely to cause difficulty in restorative dentistry?

8.

Maxillary central incisor Mandibular central incisor Mandibular lateral incisor Maxillary first premolar Mandibular canine

Which of the following describes the anatomic progression from mandibular first to third molars? A. B. C. D. E.

5.

Which of the following are the tissues immediately adjacent to the periodontal ligament? 9. A. B. C. D. E.

6.

Dentin and lamina dura Cementum and alveolar bone Gingiva and alveolar plate Bundle bone and intermediate plexus Junctional epithelium and cortical bone

A. B. C. D. E.

Saliva Adjacent contact of teeth Horizontal overlap (overjet) Deflecting function of ridges Sensory function of the periodontal ligament

10.

7 10 13 16 20

Which of the following devices accurately locates the hinge axis position of the mandible? A. B. C. D. E.

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The roots become more divergent. The crowns and roots become longer. The crowns and roots become shorter. The crowns become longer, but the roots get shorter. The crowns become shorter, but the roots get longer.

A female child's primary first molars and primary incisors have erupted, but the primary canines and primary second molars remain unerupted. What is the child's approximate age in months? A. B. C. D. E.

Which of the following offers the greatest  degree of protection for lips, cheeks, and tongue?

Maxillary central incisor Maxillary first premolar Maxillary second premolar Mandibular first molar

Kinematic facebow Arbitrary facebow Wax recording device Average value facebow Arcon articulator recorder

SAMPLE TESTLET FORMAT FOR COMPREHENSIVE PART I EXAMINATION Age Sex Height Weight B/P Chief Complaint

65 YRS Male Female 5’ 9” 240 LBS 170/100 “Lost filling in back tooth”

Medical History

Last saw his physician 2 years ago Father died of heart attack at age 52

Current Medications

diuretic for high blood pressure statin for high cholesterol low dose aspirin married, grown children retired construction foreman

Social History

SCENARIO The patient presents for replacement of a filling in tooth #19. He reports that he lost the filling over a year ago, but he delayed seeking care because the tooth has not been sensitive. Upon examination tooth #19 has a missing occlusal restoration and a fractured ML cusp.

1. This patient needs an immediate referral to his physician for A. B. C. D. E.

weight control. smoking cessation. stress management. uncontrolled hypertension. nutritional counseling.

2. Which would be the most likely consequence of the patient’s delay in having the lost restoration replaced? A. B. C. D.

Supra-eruption of tooth #14 Chewing inefficiency Loss of canine disclusion Mesial drift of tooth #18

3. At a subsequent visit the tooth is anesthetized and prepared for a crown. The patient calls the following day complaining of pain at the injection site and inability to open fully. The most likely explanation is A. B. C. D.

spasm of the temporalis muscle. trauma to the inferior alveolar nerve. injection into the medial pterygoid muscle. damage to the facial nerve during the injection.

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National Board Part I Dental Test Preparation Materials Answer Key

Anatomic Sciences 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

Microbiology-Pathology

A C D B D C A E E E

1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

Biochemistry-Physiology 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

Dental Anatomy and Occlusion

B E C D E D B D D C

1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

Sample Testlet 1. 2. 3.

D A D E B B C A E B

D A C

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B A D A B C B C C A

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