Endodontic Procedures: Apical Preparation and Barrier Formation

What is the purpose of Gates-Glidden sizes 4, 3, and 2 in the crown-down technique?

To enlarge canal orifices

When using the step-down technique, which part of the canal is flared with Gates Glidden drills or rotary files?

Coronal one third

What size file is typically used in the canal to reach the apical portion during the crown-down technique?

#70

How is the final apical preparation size determined in the crown-down technique?

By introducing progressively larger files until resistance Signup and view all the answers

Which instrument is primarily used to establish the working length in the crown-down technique?

#10 file Signup and view all the answers

In which direction is a large file like size #70 placed in the canal during apical preparation?

Clockwise rotation Signup and view all the answers

What is one of the primary objectives in cleaning and shaping the root canal system?

Remove infected soft and hard tissue Signup and view all the answers

What is an important mechanical objective in root canal instrumentation?

Complete incorporation of original canals into the prepared shape Signup and view all the answers

What is a biologic advantage of enlarged apical canals and finer needles in root canal treatment?

Allow deeper needle placement improving debridement and disinfection Signup and view all the answers

Why is it important to retain as much cervical and radicular dentin as possible during root canal instrumentation?

To prevent root fractures Signup and view all the answers

What is one of the goals that is unlikely to be fully met with current techniques in root canal instrumentation?

Complete preparation of all root canal surfaces Signup and view all the answers

Which of the following is NOT a primary objective in cleaning and shaping the root canal system?

Increasing needle placement depth Signup and view all the answers

What is the main purpose of creating an apical matrix or barrier at the proper working length during apical preparation?

To serve as a stop for gutta percha condensation Signup and view all the answers

What is the function of apical patency during cleaning and shaping procedures?

To maintain working length and prevent apical blockage Signup and view all the answers

Why is it important to avoid forcing debris through the apical foramina?

To prevent trauma to periapical tissue Signup and view all the answers

What is the average distance from the apical foramen to the apical constriction?

0.5 millimeters Signup and view all the answers

Which factor influences the choice of obturation technique in apical preparation?

Canal shape and size Signup and view all the answers

What is the significance of apical constriction in root canal treatment?

It serves as a landmark for root canal length determination Signup and view all the answers