Influence of placement technique of endodontic sealer in apical extrusion and sealer penetration into simulated lateral canals: an in vitro study

Abstract

The objective of this study is to evaluate the influence of the placement technique of endodontic sealer in apical extrusion and sealer penetration into simulated lateral canals. 60 blocks of acrylic was used with simulated root canals. These blocks are divided into 5 experimental groups (n=12) in accordance with the methods proposed for the insertion of the cement. The methods are as follows: cone covered with cement, Lima type K # 30 Spiral Lentulo, Ultrasonic Agitation (irrissônic tip), Sonic Agitation. The blocks are instrumented using the instrument R25.08 (Reciproc, VDW, Germany) and dried with absorbent paper cones in order to proceed to filling. In order to simulate a condition of approximate reality, each block will be wrapped in plastic film and part of it more or less three-quarters corresponding to the end of the canal is immersed in the agar medium (gel) packed in a plastic tube. Prior to filling the cone test will be done to check whether it is correctly positioned in the working length. Gutta-percha points calibrated 30.04 (VDW, Germany). The obturation technique to be used will be the single cone. The cement is inserted in accordance with the method of insertion of each channel group. To standardize the amount of cement it will be tooled from pilot tests already carried out will be provided 0.065 grams of cement to each specimen. The filling of lateral canals and the amount of extruded cement will be evaluated by volumetric measurements of cements by means of micro-CT images. The specimens will be scanned twice. The blocks are scanned before and after filling by means of a computerized microtomógrafo (SkyScan 1174v2, SkyScan, Kontich, Belgium). The scanning procedure is completed using voltages of 50 kV X-ray tube, 800 uA. The images are reconstructed from two-dimensional images by NRecon software (NReconv 1.6.4.8, SkyScan, Aartselaar, Belgium). And CTAN (CTAN v1.11.10.0, SkyScan) software will be used for volume measurements. The results will be tested for D'Agostino and Pearson for verification of normal distribution. In the absence of normality, will be employed the non-parametric Kruskal-Wallis. There will normally employed the parametric test ANOVA. For all tests shall be considered the significance level of 5%.