Articles Effect of Core Mass and Alloy on Cyclic Fatigue Resistance of Different Nickel-Titanium Endodontic Instruments in Matching Artificial Canals Sebastian Bürklein, Lennart Zupanc, David Donnermeyer, Karsten Tegtmeyer, and Edgar Schäfer Treatment of complex root canal systems — challenging but achievable Ralf Schlichting *This is a link to the article from roots international magazine of endodontology issue 3/21 published by Dental Tribune International. Shaping Ability and Debris Extrusion of New Rotary Nickel-Titanium Root Canal Instruments Sebastian Bürklein, David Donnermeyer, Tim Julian Hentschel, Edgar Schäfer Influence of rotational speed on torque/force generation and shaping ability during root canal instrumentation of extracted teeth with continuous rotation and optimum torque reverse motion Moe Sandar Kyaw, Arata Ebihara, Yuka Kasuga, Keiichiro Maki, Shunsuke Kimura, Pyae H. Htun, Taro Nakatsukasa, Takashi Okiji Comparison of Torque, Screw-in Force, and Shaping Ability of Glide Path Instruments in Continuous Rotation and Optimum Glide Path Motion Pyae Hein Htun, Arata Ebihara, Keiichiro Maki, Shunsuke Kimura, Miki Nishijo, Moe Sandar Kyaw, Takashi Okiji A study of simulated root tube cutting limits with NiTi rotary files IZAWA Masato, IZAWA (KIMURA) Tomoko, WADA Ken, ISHII Masahiro, KOMINE Chiaki, TSUJIMOTO Yasuhisa Impact of new cross-sectional designs on the shaping ability of rotary NiTi instruments in S-shaped canals David Donnermeyer , Anne Viedenz, Edgar Schäfer, Sebastian Bürklein