NBDE General Practice 4

Question 1

Which class of antibiotics inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins?

Accepted Answer

Beta-lactams

Answer

Beta-lactam antibiotics (penicillins, cephalosporins) inhibit transpeptidation by binding to penicillin-binding proteins, preventing cross-linking of peptidoglycan in the bacterial cell wall.

Question 2

A patient develops an allergic reaction to amoxicillin. Which antibiotic is the BEST alternative for a dental infection?

Accepted Answer

Clindamycin

Answer

Clindamycin is the preferred alternative for penicillin-allergic patients in dentistry due to its activity against oral anaerobes and streptococci without cross-reactivity.

Question 3

In which patient population is nitrous oxide/oxygen sedation contraindicated?

Accepted Answer

Patients with COPD relying on hypoxic drive

Answer

Patients with severe COPD who depend on hypoxic drive for respiratory stimulation may have respiratory depression suppressed by supplemental oxygen delivered with nitrous oxide.

Question 4

What is the significance of the 'danger space' (space 4) in the context of deep neck infections?

Accepted Answer

It provides a direct pathway for infection to spread to the posterior mediastinum

Answer

The danger space (space 4) extends from the skull base to the diaphragm, providing a direct pathway for infection to spread into the posterior mediastinum, making it life-threatening.

Question 5

A child presents after a fall with an avulsed permanent maxillary central incisor. The tooth has been out of the socket for 35 minutes and was stored dry. What is the best immediate action?

Accepted Answer

Soak in Hank's balanced salt solution for 30 minutes, then reimplant

Answer

Teeth dry for more than 60 minutes have non-viable PDL cells; soaking in HBSS or milk for 30 minutes can help rehydrate cells and improve prognosis before reimplantation.

NBDE - National Board Dental Examination Practice Test

NBDE - National Board Dental Examination Practice Test

NBDE General Practice 4