Minimally invasive endodontics (MIE) aims to preserve the maximum of tooth structure during root canal therapy. In the last 15 years there has been rapid progress and development in endodontics, making treatment procedures safer, more accurate, and more efficient. Meanwhile, reproducible results can be achieved even in difficult root canal morphologies with severe or double curvatures. In addition to various material improvements, the implementation of the surgical microscope (SM) in endodontics is an important innovation, making it possible to optimize each step in the treatment protocol in terms of substance preservation. Schlagwörter: endodontics, minimally invasive endodontics (MIE), preservation of tooth structure, surgical microscope