Efecto corrosivo sobre limas K asociados a irrigantes endodónticos. Semestre B- 2018.

Abstract

Objective: To verify and describe the corrosive effect of endodontic irrigators (Sodium hypochlorite and EDTA) and successive sterilization cycles on the surface of K files. Materials and methods: Sample 84 K files, divided into two groups, Group A: 42 Dentsply M-Access and Group B files: 42 Kendo stainless steel files, were used by undergraduate students during four cycles of use, at the end they were analyzed by optical microscope and SEM. Results: Corrosion averages were: # 15 and # 20 files of both brands grade 1, # 25 Dentsply average 0.3 and Kendo 0.6, # 30 Dentsply obtained 0 and Kendo 0.1, # 35 and # 40 grade 0 for both brands. There was no continuity of the cutting line in files # 15, # 20, # 25, # 30, # 35 and # 40 of both brands retained continuity. The average degree of corrosion-number of conductors was found in Dentsply files that instrumented 3 conduits was 0.33 and the Kendo mark was 0.58, 4 conduits the average degree of corrosion was 0.42 for Dentsply and 0.33 for Kendo, in 5 conduits it was 0.33 for Dentsply and 0.42 for Kendo, last of the 8 behaviors they obtained 0.50 for both brands. Discussion: K files are susceptible to pitting corrosion, the most affected are files # 15 and # 20 (for both brands), the same occurs with the interruption of the cutting line. Respect the relationship between degree of corrosion and number of instrumented ducts without finding specific differences between the two brands. Conclusions: Endodontic irrigators corrode the K files, the calibers most affected by corrosion, and the continuity of their cutting line were always the # 15 and # 20 independent of the brand, the files must be evaluated before use, in especially those of smaller caliber, to corroborate that they have not suffered damage, corrosion or any other damage after use that may damage the next endodontic treatment.