SHAPING ABILITY OF QUANTEC-SERIES-2000 ROTARY NICKEL-TITANIUM INSTRUMENTS IN SIMULATED ROOT CANALS - PART 1

The aim of this study was to determine the shaping ability of Quantec Series 2000 nickel-titanium instruments in simulated canals. A total o f 40 simulated root canals made up of four different shapes in terms o f angle and position of curvature were prepared by Quantec instruments using the technique recommended by the manufacturer, Part 1 of this t wo-part report describes the efficacy of the instruments in terms of p reparation time, instrument failure, canal blockages, change in canal length and three-dimensional canal form. The time necessary for canal preparation was on average 5.7 min and was significantly influenced (P < 0.01) by canal shape, One instrument fractured and three size nine instruments deformed; however, canal shape did not influence significa ntly instrument failure, All of the canals remained patent, none becam e blocked with debris. The majority of the canals maintained working d istance (26 out of 40), however the mean change in length differed sig nificantly (P < 0.05) between canal types. Overall, canals with 40 deg rees curves lost length whilst those with 20 degrees curves gained in length. Examination of intracanal impressions revealed that preparatio n with Quantec Series 2000 instruments produced canals with definite a pical stops, smooth canal walls and good flow and taper, However, the quality of apical smoothness and flow was influenced significantly (P < 0.0001) by canal shape with specimens having 40 degrees canals displ aying less desirable qualities. Under the conditions of this study, Qu antec Series 2000 rotary nickel-titanium instruments prepared simulate d canals rapidly, safely and with good three-dimensional form.