Endodontics was traditionally performed by hand with radiographic confirmation. To perform a root canal treatment often meant working inside a BLACK HOLE and many results were achieved by chance. Today, every challenge existing in the straight portion of the root canal system, even if located in the most apical part, can be easily seen and often solved under the microscope.The simple premise for using the microscope is that light plus magnification equals excellence. It certainly makes sense that if the clinician can see something more clearly and magnified, he or she can better evaluate and treat that object. As some surgeons say, if you see it, you can protect it. This adage also applies to endodontics.The introduction and wide spread use of the operating microscope together with the power of ultrasonics and instruments for microendodontics are areas that have changed the face of endodontics.