Comparative analysis of different instrumentation types and adhesive systems in fiberglass pin retention in flattened channels

The objective of this work was to compare the adhesive strength of the prefabricated fiberglass pin in flat channels by means of the tensile removal force. For this, 48 extracted human inferior incisors were selected and randomly divided into four experimental groups of 12 samples each. All teeth were sectioned horizontally, leaving 2 millimeters of dental remnant, so that an average length of 16 millimeters was obtained. The endodontic treatment was performed with the PROTAPER NEXT and iRACE rotary systems and with the RECIPROC and WAVE ONE reciprocating systems up to the diameter of 0.40 and filled with gutta percha cones according to the technique used for each group. For the clearance and preparation of the root canal for cementation of the pins, 5 mm of obturator material was left in the apical third. The cementation of the fiberglass pins was performed according to the adhesive agent. The specimen was placed in the universal test machine and the axial tensile loading at the speed of 0.5 mm/min was applied. Then, the data were analyzed by means of the analysis of variance ANOVA double factor at the 5% level and the unit analyzed was in Kgf. The results showed differences between the strength means in the different groups, where the self-etching adhesive Ambar Universal showed superiority compared to the conventional Ambar adhesive. There was no statistically significant difference between the automated systems, however, the Wave One group presented a higher degree of adhesiveness when compared to the iRace group.