DMD DMD Endodontics and Pulp Biology 2

Question 1

What is the purpose of the working length in root canal therapy?

Accepted Answer

To determine the length to which instrumentation and obturation should extend, ideally 0.5–1 mm from the radiographic apex

Answer

The working length defines the distance from a reference point to the apical stop, typically 0.5–1 mm short of the radiographic apex, to prevent overextension.

Question 2

Which irrigant is considered the gold standard for root canal disinfection?

Accepted Answer

Sodium hypochlorite (NaOCl)

Answer

Sodium hypochlorite is the gold standard root canal irrigant due to its ability to dissolve organic tissue and kill a broad spectrum of microorganisms.

Question 3

What is the role of EDTA in root canal treatment?

Accepted Answer

To remove the smear layer by chelating calcium ions from dentin

Answer

EDTA (ethylenediaminetetraacetic acid) is a chelating agent that removes the inorganic smear layer from canal walls, enhancing irrigant penetration.

Question 4

Which obturation technique uses a heated carrier to deliver gutta-percha into the canal?

Accepted Answer

Both A and C

Answer

Both Thermafil and carrier-based obturator techniques use a heated plastic or metal carrier coated with gutta-percha that is inserted into the canal.

Question 5

Which sealer property is most critical for a successful root canal obturation?

Accepted Answer

Good adhesion and adequate sealing of lateral and accessory canals

Answer

An ideal endodontic sealer must adhere well to dentin and gutta-percha and seal lateral and accessory canals to prevent bacterial re-colonization.

DMD - Doctor of Dental Medicine Practice Test

DMD - Doctor of Dental Medicine Practice Test

DMD DMD Endodontics and Pulp Biology 2