ABSTRACT
OBJECTIVES: The aim of this study was to compare the volume variation and maintenance of the root canal position when using the ProGlider 16.02 (PG) and the WaveOne Gold Glider 15.02 (WOGG) file systems for glide path preparation. MATERIALS AND METHODS: Twenty-four moderately curved mesiobuccal canals of maxil-lary first molars were selected and randomly divided into two groups: PG and WOGG. The selected teeth were scanned using microtomography before and after root canal preparation to assess centralization and linear transport at 1, 3, 5, and 7 mm from the apical foramen. STATISTICAL ANALYSIS: The data were analyzed with the Mann-Whitney U test. The level of significance was 5%. RESULTS: There were no significant differences in volume variation or root canal transport (p > 0.05). There was a significant difference in the centralization of the root canal at 3 mm from the foramen (p < 0.05). CONCLUSIONS: WOGG and PG instruments presented similar results regarding the root canal volume increase and transport. WOGG caused higher decentralization at 3 mm from the apical foramen.
ABSTRACT
O objetivo desse trabalho foi analisar a modelagem produzida em canais curvos após a instrumentação comparando os sistemas rotatórios ProTaper Next e Twisted File. Utilizaram-se 30 blocos com canal simulado confeccionados de resina acrílica com curvaturas padronizadas de 30° e 17 mm de comprimento. Os blocos acrílicos foram divididos em dois grupos, A e B (n=15). O grupo A: o preparo químico-mecânico foi realizado com limas rotatórias ProTaper Next (Dentsply), X1 #17 de diâmetro inicial e 0,04 de conicidade, e X2 # 25 de diâmetro inicial e 0,06 de conicidade, funções pré-ajustadas no motor Smart-X plus com autorreverso acionado e utilizou-se o torque no valor de 3N/cm e velocidade de 300 rpm, com movimentos de limagem sem pressão apical até atingir o comprimento de trabalho. O grupo B: realizou-se com limas rotatórias Twisted File (SybronEndo) equivalente a #20 (0,04) e # 25 (0,04) de diâmetro inicial, semelhante ao outro grupo. Para a análise da modelagem antes e após a realização dos preparos, os canais simulados foram posicionados sobre uma superfície firme e fotografados por uma câmera fotográfica digital obedecendo sempre à mesma posição e distância focal. As imagens obtidas foram manipuladas no programa Corel Draw CS6. Foi determinado o local da imagem que seria medido aproximadamente a 13 mm da embocadura onde se localiza o início da curvatura. Os instrumentos ProTaper Next obtiveram uma modelagem de 16,36% se comparado com os instrumentos Twisted File (10,71%) em relação à média inicial (AU).
This study aimed to analyse the shaping of curved canals after instrumentation comparing the systems ProTaper Next and Twisted File. We utilized 30 simulated canal acrylic blocks with standard 30 degrees of curvature and 17 mm length. The blocks were divided in two groups, A and B (n=15). Group A: the canal was prepared with ProTaper Next Files (Dentsply), X1 #17 of initial diameter and taper (0,04), X2 #25 of initial diameter and taper (0,06), preadjusted functions on X-Smart Plus device, auto-reverse, 3N/cm² torque and 300rpm speed. We used filing movements without apical pressure until the work length. Group B: this group used Twisted File system (SybronEndo) equivalents of #20 (0,04) and #25 (0,04) of initial diameter, following group A. For shaping analysis before and after preparing, the simulated canals were positioned on a firm and stable surface and were photographed with a digital camera always with the same focal distance and position. The images were processed at Corel Draw CS6 software. We determined the image position measured at approximately 13 mm of the canal entrance, at the beginning of the curvature. The ProTaper Next System had a superior shaping of 16,36% comparing with Twisted File which achieved a shaping of 10,71%, comparing with the initial values (AU).
