ANALYSIS OF APICAL TRANSPORT AND CENTRALIZATION OF PREPARATION OF MECHANIZED NICKEL-TITANIUM INSTRUMENTS IN LOWER MOLARS: PROTAPER GOLD AND PRODESING LOGIC.
Endodontics, Apical deviation, Micro CT, NiTi files
This research aims to evaluate the morphological changes resulting from the instrumentation of severely curved root canals and to compare the ProTaper Gold and Prodesign Logic systems by analyzing the apical transport and the centralization of root canal preparation. The sample consisted of twenty lower human molar mesial roots that met the inclusion criteria, including: intact roots, complete root formation and intact pulp chamber. This sample underwent clinical selection, disinfection and storage, subsequently radiographic selection according to the Schneider method. After this step, the access cavities and the glide path were prepared, only the mesial roots were used in the study in question. For the numbering of the sample, the teeth were paired based on the parameters of volume, surface area and three-dimensional image of the dental elements, and thus divided into 2 groups: G1 - ProTaper Gold and G2 - Prodesign Logic. The procedures will be performed according to the manufacturer's instructions and the instruments will be discarded after use in the respective groups. During instrumentation the canals will be irrigated, and soon after dried with sterile absorbent paper tips. Measurements will be divided by thirds: at 3mm, 5mm and 7mm from the apex, and the variables apical transport and centralization will be evaluated by images obtained by computed microtomography (micro-CT) acquisition. To evaluate the resistance variable of the instrument will be performed the tests: buckling resistance and flexion at 45º, using the universal testing machine EMIC DL-200 MF. And finally, the results will be submitted to statistical tests, in order to test the hypotheses raised in this research, which was reviewed and approved by the Research Ethics Committee of Hospital Onofre Lopes (HUOL).