title: Penetration depth of nickel titanium and stainless steel finger spreaders in curved root canals.
abstract: OBJECTIVE
  To compare, radiographically, the differences in the penetration depths of nickel titanium and stainless steel finger spreaders in curved root canals.
  
  
  METHODS
  A comparative study.
  
  
  METHODS
  The study was carried out at Armed Forces Institute of Dentistry, Rawalpindi, Pakistan, from September 2001 to June 2002.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  Nickel-titanium spreaders may give better results for lateral condensation in curved canals because of their deeper penetration.
authors.affiliation: Department of Operative Dentistry, Armed Forces Institute of Dentistry, Rawalpindi. irfanuk69@hotmail.com
authors.forename: Muhammad Bakhsh
authors.initials: MB
authors.lastname: Sobhi
authors.forename: Irfanullah
authors.initials: I
authors.lastname: Khan
mesh_terms: D000293:Adolescent; D000328:Adult; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008963:Molar / Q000000981:diagnostic imaging; D009532:Nickel; D011859:Radiography; D012389:Root Canal Obturation; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods; D013193:Stainless Steel; D014025:Titanium
chemical_list: D013193:Stainless Steel; D009532:Nickel; D014025:Titanium