Application of Modular Design Methodology for Endodontic Instrument Fatigue Test Bench

Abstract

In endodontic procedures, Nickel-Titanium (NiTi) instruments are used, which adapt to the geometry of root canals. These alloys have favored the mechanical properties of the files. However, the high cost of these instruments leads to repeated use, increasing the risk of fatigue fracture during treatment. Different brands and references of endodontic instruments are offered on the market, so it is essential to characterize the mechanical properties of the files and their behavior when subjected to fatigue loads. So far, there is no standardization for the tests used to check their fatigue resistance, and therefore, in each research, equipment, and analysis methodology are proposed. In this project, a test bench is developed for fatigue testing of endodontic instruments without material, cross-section, and external design restrictions, allowing static and dynamic tests. For the test bench, the modular design strategy is applied to identify components susceptible to acquiring this characteristic, using easy-to-acquire elements and manufacturing techniques such as 3D printing, favoring the modularization of the design. The device moves in two axes, X and Y, and it is possible to regulate the depth of entry of the instrument into the channel. It also has an electronic system that automates the dynamic and static test, an LCD screen for menu access, and records the number of cycles to file breakage.