Comparison of the Cyclic Fatigue between Two New Different Reciprocating Files in Curved Root Canals. A Systematic Review and Meta- Analysis.

Objectives: Teeth with a curved root morphology may challenge clinicians in achieving an adequate root canal shaping and cleaning without separation of the file. Therefore, many of nickel-titanium (Ni-Ti) has been evolved over years in order to minimize the risk of the separation. Recently, single file nickel- titanium (Ni-Ti) reciprocating system has been a major breakthrough in the field of endodontics. Thus, the aim of this study is to compare the cyclic fatigue resistance between two new different reciprocating files Reciproc Blue and Waveone Gold in curved root canals using meta-analysis with different parameters.
Methods: A comprehensive electronic literature search for Reciproc Blue and WaveOne Gold using PubMed and Google Scholar was initially conducted in April 2018 and updated in December 2018. Inclusion and exclusion criteria were then established. Twenty-four studies were qualified for the systematic review, and only six studies were considered for the systematic review using cyclic fatigue resistance as the main parameter.
Results: The mean number of cycles to fracture for the Reciproc Blue and Waveone Gold systems ranged from 876.5+161.3 to 2875.8+105.3, and 409.3+77.24 to 1737+376.3, respectively. The pooled difference in mean cycles to fracture 338.614 (-94.66 – 771.89), but the difference was not statistically significant (p=0.126). However, The mean time to fracture for the Reciproc Blue and Waveone Gold systems ranged from 211+30 sec to 221.83+31.05 sec ,and 141.85+18.43 sec to 549.54+186.7 sec, respectively. The pooled difference in mean time to fracture 185.48 (48.69 – 322.27) sec and the difference was statistically significant (p=0.008).
Conclusions: TF “ Time to Fracture” of the Reciproc Blue is superior to Waveone Gold by three minutes. Reciproc Blue is more resistant to cyclic fatigue than WaveOne Gold. However, with regard to other parameters, mixed results were obtained. Well-designed randomized clinical trials comparing both systems under the same experimental conditions should be done in future studies