Balanced force, crown-down preparation, and inject-R Fill obturation

The balanced force concept proposes that instruments are guided by the canal structure when rotational motion is used. Changing the direction of rotation controls the probability that instruments will become overstressed and controls the cutting of structure to give an efficient result. Crown-down progression of the cleaning and shaping is possible as a result of predetermined preparations and use of a recent modified tip file design, the Flex-R file. Preparation time is minimized, while cleaning is enhanced by the crown-down approach. After cleaning and shaping, the intracanal aseptic state must be preserved by obturation. System B condensation followed by Inject-R Fill, back-filling is described as an efficient method to accomplish this obturation.