Penetration depth of nickel titanium and stainless steel finger spreaders in curved root canals

ABSTRACT

To compare, radiographically, the differences in the penetration depths of nickel titanium and stainless steel finger spreaders in curved root canals. Design: A comparative study. Place and Duration of Study The study was carried out at Armed Forces Institute of Dentistry, Rawalpindi, Pakistan, from September 2001 to June 2002. Materials and Fifty patients with curved mesial canals of their mandibular first molars were randomly selected for the study. The angle of curvature for each root canal was radiographically determined before instrumentation. Canals were prepared by K flexo file using the step back preparation technique. The apical preparation was done upto no. 30 and cervical flaring upto no. 45. Gates Glidden drills nos. 2-4 were used in the cervical 2-3 mms of the canal. A no. 20 stainless steel and a fine medium nickel titanium finger spreader were inserted alternately into the same prepared canal and radiographed using the paralleling technique. The distance from the tip of the spreader to the apex of the root was measured radiographically by vernier calliper. Penetration of nickel-titanium finger spreader was significantly [p<0.05] deeper than the stainless steel spreader of comparable size. The ease of stainless steel penetration decreased with increasing angle of curvature of the canal. Nickel-titanium spreaders may give better results for lateral condensation in curved canals because of their deeper penetration