Cutting efficiency of heat-treated nickel-titanium single-file systems at different incidence angles

Cutting efficiency of Reciproc R25 (REC) and Reciproc blue R25 (REB) at different inclinations was evaluated. Sixty new files were tested at 90 degrees, 70 degrees and 45 degrees of inclination in relation to the sample (n = 10), using a customised machine. All files were activated in reciprocation against standardised gypsum blocks for 120 s. Cutting efficiency was determined by measuring the block weight loss with an analytical balance and measuring the length of the block surface cut using a digital calliper. Data were statistically analysed (two-way ANOVA, Bonferroni t-test) with the significance level set at P < 0.05. There was no difference for REC among the tested angles. REB had no statistical difference between 90 degrees and 70 degrees; however, its cutting efficiency significantly increased at 45 degrees. There was a significant difference between REC and REB at 45 degrees only. Under these conditions, increased file inclination to 45 degrees and blue heat treatment improved cutting efficiency of reciprocating files.

Automated summary

The study evaluated the cutting efficiency of Reciproc R25 and Reciproc blue R25 at different inclinations. It was found that Reciproc blue R25 showed significantly increased cutting efficiency at 45 degrees inclination. This suggests that proper angles and heat treatment can improve the cutting efficiency of reciprocating files.