Photomicrographic Evaluation Of Filling In Root Canals Prepared With2Kinds Of Files And Obturated By2Kinds Of Gutta-percha:an Invitro Study

Aim:To evaluate quality of root filling achieved with a0.02or a0.06taperedgutta-percha master cone using cold lateral condensation following root canalpreparation with stainless steel and nickel–titanium Protaper universal rotaryinstruments.Methods:Forty extracted human maxillary anterior teeth were randomly divided intofour groups. In Group A: the canal was prepared by stainless steel hand files andobturated using0.02taper master gutta-percha cone by lateral-compaction technique.InGroup B：the canal was prepared by stainless steel hand files and obturated using0.06taper master gutta-percha cone by lateral-compaction technique.In Group C: the canalwas prepared by nickel–titanium Protaper universal rotary instruments and obturatedusing0.02taper master gutta-percha cone by lateral-compaction technique. In Group D:the canal was prepared by nickel–titanium Protaper universal rotary instruments andobturated using0.06taper master gutta-percha cone by lateral-compaction technique.AH Plus was used as a sealer in all groups. After storing the teeth in100%humidity forseven days at37°C, the roots were sectioned at2mm and8mm and processed in agrinding machine for metallographic samples. Photomicrographs were obtained withmetallographic optical microscope and digital image analysis is carried out to calculatecanals, gutta-percha-filled and voids areas. Using these values percentage ofgutta-percha filled area(PGP) and percentage of void filled area(PV) arecaluculated. The data obtained was subjected to statistical analysis using Mann-WhitneyU test.Results:（1）At2mm level, there was no statistically significant difference observedbetween Group A and Group B、Group A and Group C、Group B and Group D、Group C and Group D in terms of PGP and PV (p>0.05);（2）At8mm level, there was no statistically significant difference observed betweenGroup A and Group B、Group A and Group C、Group B and Group D、Group C andGroup D in terms of PV (p>0.05).（3） At8mm level, Group D has higher mean percent gutta-percha-filled area thanGroup C in terms of PGP (p<0.05); Group D has higher mean percentgutta-percha-filled area than Group B in terms of PGP (p<0.05); Group C has highermean percent gutta-percha-filled area than Group A in terms of PGP (p<0.05)Conclusions:（1）At middle1/3rd of root canal filling, with the same taper mastergutta-percha cone, nickel–titanium Protaper universal rotary instruments reduces theextent of microleakage when compared with stainless steel instruments. The canalsprepared with nickel–titanium Protaper universal rotary instruments and obturated with0.06tapered gutta-percha master cone will provide a better sealing capacity.（2） At apical1/3rd apical of the canals: canals prepared with either stainless steelinstruments or nickel–titanium Protaper universal rotary instruments and obturated with0.02or a0.06tapered gutta-percha cone using cold lateral condensation possess a goodapical sealing capacity.