[Clinical effect of the use of dental operating microscope and ultrasonic instruments in the management of blocked canals].

Objective: To evaluate the effect of using dental operating microscope and ultrasonic instruments in treating blocked canals.

Methods: The etiology of canal blockage included calcification, broken instruments, posts, resinifying, etc. 236 blocked canals were treated with ultrasonic tips under dental operating microscope. The success rate was calculated.

Results: 178 blocked canals were successfully managed with a success rate of 75.4%. The success rate of each category of the blocked canals were: 71.7% for calcified canals, 81.1% for broken instruments, 100% for canals blocked by posts, 62.5% for canals blocked by resinifying therapy, and 84.1% for canals blocked by filling materials.

Conclusion: The use of dental operating microscope and ultrasonic instruments is proved to be an effective method in the management of blocked canals.