RELATION BETWEEN THREE INSTRUMENTATION LEVELS AND THE FILLING OF THE ROOT CANAL APICAL THIRD

Abstract

This study evaluated the relation between three levels of instrumentation and the quality of the filling of the root canal apical third. Sixty root canals were prepared using instruments in continuous rotation or reciprocating motion, distributed into three groups according to a pre-established working length (WL): G-1 (WL=CD-1); G0 (WL=CD); G+1 (WL=CD+1). Each group was subdivided (n=10) into two groups, according to foraminal intervention: G-1BP: Buchanan patency and G-1MF: manual file; G0Rot: rotary; and G0Rec: reciprocating preparation; G+1Rot: rotary; and G+1Rec: reciprocating preparation. Groups G-1BP, G-1MF, G0Rec and G+1Rec were prepared up to the WL with an R25 file and groups G0Rot and G+1Rot with a Prodesign S file. Obturation level for all groups was established at CD-1. Images at 1, 2, and 3mm and at the foramen were obtained to assess the foramen and the apical third filling and whether there was overfilling. Data analyzes was performed using Pearson's Chi-Square (P = 0.05). There was no association between the preparation and gutta-percha cone level (p>0.05). Sealer’s leakage was greater in G0 and G+1 than in G-1. In G0 and G+1, 63% and 65% of the specimens had the entire apical foramen filled, while in G-1: 17.6%. In the 1mm section, 100% of the specimens were filled in G0 and G+1, whereas in G-1: 64.7% (p<0.05). There was no association between kinematics and obturation quality (p>0.05). It was concluded that there was no association between preparation levels and overfilling; the preparation levels in CD and CD+1 had a higher occurrence of endodontic sealer extrusion and filling of the foramen and apical third; kinematics did not influence the foramen and apical third filling.