Comparison of radiographic density and compaction index of root canal obturation using nickel titanium or stainless-steel spreaders

Background: Both nickel titanium and stainless-steel spreaders are available. The obvious advantage of nickel titanium spreader over stainless steel spreaders is greater penetration in curved canals. Objective: To compare the radiographic density and compaction index of root canal obturation using nickel-titanium or stainless-steel spreaders in curved canals. Methods: In this experimental study the primary weight of 30 acrylic blocks with 45o degrees of apical curvature were measured by a scale (W1). After canals were prepared by step back master apical up to file #30 all blocks were weighed again (W2) and randomly divided in two groups of 15each. All canals were obturated by Cold lateral compaction technique (with nickel-titanium in one group and stainless-steel finger spreaders in another group). After all blocks were reweighed (W3), compaction index (W3-W2/W1-W2) was calculated. One radiograph was taken for each sample. Apical density of the apical third of each canal was measured by digital transmission densitometer. Data were analyzed statistically using T-test. Findings: Mean compaction index for nickel-titanium group was 7.67±2.38 and for stainless-steel group was 9.14±4.06. There was no significant difference between two groups. Mean radiographic density of obturation was 2.05±0.14 in nickel-titanium group and was 2.07±0.21 in stainless-steel group. There was no significant difference between two groups. Conclusion: It is concluded that nickel-titanium spreaders are not superior than stainless-steel spreaders in obturating curved canal.