Cone beam computed tomography for centering ability, dentin thickness at critical canal furcation, canal transportation and dentin volume analysis using reciprocating k-file and hybrid technique reciprocating-rotary protaper endo system-an in-vitro study

Aim: The aim of the present study was to compare and evaluate the root canal shaping ability of Hybrid combination of Nickel-Titanium reciprocating-rotary Protaper files and hand NiTi files in Endo-Express hand-pieces with “concept of Pre-prepared canal for Rotary”.
Methodology: Forty canals straight and curved(200-300) of maxillary first premolars with two roots Buccal and Palatal were selected and randomly assigned to four experimental groups. Gr.1 (RPRT)s:Buccal straight roots (n=10) shaping was done with hybrid combination of alternate hand NiTi in endo-Express Reciprocating-rotary Protaper. Gr.2 (RP)s: Palatal straight roots (n=10) shaping was done with Hand NiTi K-files in Endo-Express hand-pieces in reciprocating motion. Gr.3 (RPRT)c: Buccal curved roots (n=10) shaping was done with hybrid combination of alternate hand NiTi in endo-Express Reciprocating-rotary Protaper. Gr.4 (RP)c:shaping was done with Hand NiTi K-files in Endo-Express hand-pieces in reciprocating motion. Cone Beam Computed Tomography used to assess Centring ability, canal transportation, Total dentin Volume loss and dentin thickness at furcation, Before and after canal preparation. Statastic Descriptive analysis with ANOVA and Tukey’s post Hoc test was applied.
Results: There was no statistical significant difference at any level 1-,3-,5-,7-,and 9mm in centring ability and canal transportation of canal in all four groups (P>0.05). Total dentin volume loss for group (1 &2) was 6.64% and for group (3&4) was 7.86%. Dentin thickness at furcation Bs-1.52±0.02, Ps-2.07±0.28, Bc-1.45±0.15 and Pc-1.5±0.33 after canal preparation.
Conclusion: Hybrid combination technique of RPRT with the concept of pre-prepared canal is safest to use for Protaper Rotay without the fear of fracture of instrument. Excellent centring ability without any canal deviation can be achieved. The disadvantage is more armamentarium is required for good root canal preparation.