Evaluation of 2 Nickel-Titanium Instrument Systems in Shaping Root Canals

Abstract

Aim:To evaluate root canal enlargement following mechanical shaping using 2 nickel titanium rotary systems in simulated curved canals. Materials and Methods: Thirty simulated canals in resin blocks were divided into two experimental groups, each comprising 15 resin blocks, and prepared with Twisted files (TF) and RaCe rotary files using crown-down technique. Preoperative and postoperative photographs, taken using a digital camera, were superimposed and aberrations were recorded. The amount of resin removed was measured at 11 different points, beginning at the apical terminus of the canal. Instrument failure, outer and inner width measurements, transportation rate, and centering ability were recorded on each central canal path and differences between groups were statistically analyzed using Student's t test. Results: No instrument fracture occurred during preparation. RaCe instruments removed more material from the outer canal walls in the apical section (p < 0.01) and from the inner canal walls in the middle section (p < 0.01) of the canals compared to TF. However, canals prepared with TF instruments resulted in less transportation (p < 0.05) in the middle section. No significant differences were found between the two groups in terms of centering ability in apical, middle, or coronal sections. (p > 0.05). Conclusions: RaCe instruments removed more resin from the outside of the apical curvature and from the inner side of the coronal curvature compared to TF. In addition, mean transportation amount was signifycantly high for RaCe in middle section (i.e., coronal curvature). Regarding canal centering ability, however, both instruments retained original canal geometry and performed similarly.

Üç Farkli Ni̇kel-Ti̇tanyum Döner Alet Si̇stemi̇ni̇n Vücut Isisindaki̇ Döngüsel Yorgunluk Di̇rençleri̇ni̇n Karşilaştirmali Olarak Değerlendi̇ri̇lmesi̇

“…25 Bu çalışmanın sonuçlarıyla benzer olarak, TF eğesi ve RaCe (FKG Dentaire) eğelerinin döngüsel yorgunluk direncinin karşılaştırıldığı çalışmalarda TF eğelerinin döngüsel yorgunluk direncinin RaCe eğesinden daha yüksek olduğu bildirilmiştir. 26,27 Uslu ve ark. 'nın kanal sıcaklığında 2Shape (MicroMega), TF ve ESX (ESX ) eğelerinin döngüsel yorgunluk direncine karşı dayanımını inceledikleri çalışmalarında, TF eğesinin, ESX eğesinden önemli ölçüde daha iyi döngüsel yorgunluk direnci sergilediği gösterilmiştir.…”