ADAT Dental Pharmacology 2 — Questions and Answers
Question 1: What is the primary mechanism by which chlorhexidine reduces dental plaque?
- Inhibits bacterial protein synthesis
- Disrupts bacterial cell membranes and binds to oral surfaces for sustained release (Correct answer)
- Blocks bacterial DNA replication
- Chelates calcium from bacterial cell walls
Correct answer: Disrupts bacterial cell membranes and binds to oral surfaces for sustained release
Chlorhexidine is substantive—it binds to oral tissues and is slowly released, disrupting bacterial cell membranes over time.
Question 2: A patient taking warfarin needs a tooth extraction. Which antibiotic, if prescribed, is most likely to significantly enhance anticoagulation?
- Amoxicillin
- Metronidazole (Correct answer)
- Azithromycin
- Clindamycin
Correct answer: Metronidazole
Metronidazole inhibits CYP2C9, reducing warfarin metabolism and significantly increasing INR and bleeding risk.
Question 3: Which opioid is preferred for dental pain management in patients with renal impairment?
- Morphine
- Codeine
- Hydromorphone (Correct answer)
- Tramadol
Correct answer: Hydromorphone
Hydromorphone is preferred in renal impairment because its active metabolites accumulate less than those of morphine or codeine.
Question 4: Which fluoride compound is most effective for remineralizing early enamel carious lesions in-office?
- Sodium fluoride 0.05% rinse
- Stannous fluoride 0.4% gel
- Acidulated phosphate fluoride (APF) 1.23%
- Sodium fluoride 5% varnish (Correct answer)
Correct answer: Sodium fluoride 5% varnish
Sodium fluoride 5% varnish (22,600 ppm F) applied in-office provides the highest concentration for effective remineralization of early lesions.
Question 5: What is the primary reason epinephrine-containing local anesthetics are used cautiously in patients taking non-selective beta-blockers?
- Risk of hypertensive crisis due to unopposed alpha-adrenergic stimulation (Correct answer)
- Increased risk of cardiac arrhythmia from beta-receptor overstimulation
- Reduced local anesthetic efficacy due to altered blood flow
- Risk of hypoglycemia from insulin interaction
Correct answer: Risk of hypertensive crisis due to unopposed alpha-adrenergic stimulation
Non-selective beta-blockers leave alpha receptors unopposed, so epinephrine can cause severe hypertension through vasoconstriction.
Question 6: Which antifungal agent is the first-line treatment for oral candidiasis in immunocompetent dental patients?
- Amphotericin B
- Fluconazole systemic
- Nystatin topical (Correct answer)
- Itraconazole
Correct answer: Nystatin topical
Topical nystatin (rinse or lozenge) is the first-line treatment for oral candidiasis in immunocompetent patients due to its effectiveness and minimal systemic absorption.
ADAT Dental Pharmacology 2
What is the primary mechanism by which chlorhexidine reduces dental plaque?