E Schäfer1, H Florek. 1. Department of Operative Dentistry, University of Münster, Münster, Germany. eschaef@uni-muenster.de
Abstract
AIM: To compare the shaping ability of K3 rotary nickel-titanium instruments with stainless steel K-Flexofiles manipulated by hand. Part 1 of this two-part report describes the efficiency of these two instruments in simulated curved root canals. METHODOLOGY: Simulated canals with 28 degrees and 35 degrees curves in resin blocks were prepared by K3 instruments with a rotational speed of 250 r.p.m. using a crown-down preparation technique, or by K-Flexofiles using a reaming motion -i = 24 canals in each case). All canals were prepared up to size 35 at the end-point of preparation. Pre- and postinstrumentation images were recorded, and assessment of canal shape was completed with a computer image analysis program. Material removal was measured at 20 measuring points, beginning 1 mm from the apex. Incidence of canal aberrations, preparation time, changes of working length and instrument failures were also recorded. RESULTS: In comparison with stainless steel K-Flexofiles, rotary K3 instruments achieved better canal geometry and showed significantly less canal transportation (P < 0.05) Eleven K3 instruments and none of the K-Flexofiles fractured during preparation (P < 0.05). Between both the canal types, K3 was significantly faster (P < 0.001) than K-Flexofiles. Both instruments maintained a good working distance. CONCLUSIONS: K3 instruments prepared curved canals rapidly and with minimal transportation towards the outer aspect of the curve. Fractures occurred significantly more often with K3.
AIM: To compare the shaping ability of K3 rotary nickel-titanium instruments with stainless steel K-Flexofiles manipulated by hand. Part 1 of this two-part report describes the efficiency of these two instruments in simulated curved root canals. METHODOLOGY: Simulated canals with 28 degrees and 35 degrees curves in resin blocks were prepared by K3 instruments with a rotational speed of 250 r.p.m. using a crown-down preparation technique, or by K-Flexofiles using a reaming motion -i = 24 canals in each case). All canals were prepared up to size 35 at the end-point of preparation. Pre- and postinstrumentation images were recorded, and assessment of canal shape was completed with a computer image analysis program. Material removal was measured at 20 measuring points, beginning 1 mm from the apex. Incidence of canal aberrations, preparation time, changes of working length and instrument failures were also recorded. RESULTS: In comparison with stainless steel K-Flexofiles, rotary K3 instruments achieved better canal geometry and showed significantly less canal transportation (P < 0.05) Eleven K3 instruments and none of the K-Flexofiles fractured during preparation (P < 0.05). Between both the canal types, K3 was significantly faster (P < 0.001) than K-Flexofiles. Both instruments maintained a good working distance. CONCLUSIONS: K3 instruments prepared curved canals rapidly and with minimal transportation towards the outer aspect of the curve. Fractures occurred significantly more often with K3.
Authors: E Pedullà; G Plotino; N M Grande; G Avarotti; G Gambarini; E Rapisarda; F Mannocci Journal: Clin Oral Investig Date: 2016-02-15 Impact factor: 3.573
Authors: J M V Raghavendra Reddy; Prasanna Latha; Basavana Gowda; Varadendra Manvikar; D Benal Vijayalaxmi; Kalyana Chakravarthi Ponangi Journal: J Int Oral Health Date: 2014-02-26