Recent approach for working length determination

Working length determines the extent of canal cleaning and shaping. This limits the penetration depth of subsequent instruments and determines the ultimate form of root canal preparation. Regardless of whether it is in dentin or cementum; the most clinically relevant working length landmark is the apical constricture. There are various methods that can be used for determining the working length of the tooth. Knowledge of apical anatomy prudent use of radiographs and the correct use of an electronic apex locator will assist practitioners to achieve predictable results.