The interior of each healthy tooth contains pulp, which consists of blood vessels and nerves.  In the case of deep decay or when a large piece of tooth has broken off, bacteria can penetrate the pulp and cause an extremely painful inflammation.  When treating the diseased tooth, it is particularly important to remove all the infected pulp, to avoid complications later on.

The process of determining the length of the roots (each tooth has between 1 and 4 canals) and widening them is computer-guided and employs modern, flexible instruments made from a titan alloy.  The use of such instruments means that even extremely twisted and very fine canals to be properly prepared.  The number of disinfection fillings to be applied depends on the severity of the infection (bacteria).  These fillings consist of calcium hydroxide paste and remain for days or weeks in the root canals.  The final filling consists of gutta-percha.