Design features of any root canal instrument are determined primarily by the aim and the method of its use. Design features are likewise influenced by the material’s properties and its processing methods. On the other hand, all these factors determine the instrument’s operation technique and the range of objectives that could be solved by its use.
There are a vast number of different root canal instruments and systems. From time to time, new instruments or modifications of the existing systems appear. It is not always easy for dental practitioners to be familiar with the whole variety of options.
Nevertheless, understanding the basic features of root canal instruments and their operation principles can help the clinician use these instruments more effectively, and significantly reduce the probability of mistakes.
Preparatory steps completed prior to reviewing the root canal instrument’s design features ought
to clarify some of the basic definitions and terms. Any root canal instrument represents a cutting instrument for the mechanical processing of the root canal wall.
All root canal instruments can be divided into two groups depending on how they are used:
The non-cutting part is an element of the working section, which has a smooth cylindrical form and is positioned between the cutting part and the shank (Fig 1). As a rule, the non-cutting part has one or more measuring lines and/or the rubber stop. Both of them allow for the controlling of the 'working length', limiting the instrument insertion into the root canal during the preparation.
The tip is another element of the working part that performs the guiding function (Fig 1). The tip might have a sharp or rounded (bullet-like) conﬁguration, depending on whether it appears:
|Chow et al16||-15||-43|