What preoperative practices reduce the risk of instrument separation in a canal?

• A. Establish a glide path, maintain patency, avoid excessive force, rotate with torque control, and use properly matched file systems
• B. Use excessive force
• C. Skip glide path
• D. Use mismatched files

Answer: (A)

Reducing instrument separation comes from managing the stresses on the file during canal shaping. Creating a glide path gives the subsequent shaping files a smooth, negotiable route, which minimizes binding and the torsional stress that can lead to fracture. Maintaining patency keeps the canal open and free of debris so the files don’t bind or stall, which would otherwise spike torque. Avoiding excessive force is critical because pushing hard past resistance can overload the file beyond its strength and cause separation. Using torque control ensures the rotary motion stays within safe limits and prevents sudden overload that can cause separation. Finally, selecting properly matched file systems means the instruments, their speeds, and their gaps and flexibilities work together cohesively; mismatched systems create uneven stresses and higher risk of separation. When these practices aren’t followed—skipping a glide path, letting force dominate, or using incompatible files—the chance of instrument separation increases due to greater binding, higher torque, and fatigue.