Avaliação da adaptação marginal de componentes sobre implantes, de torque interno e convencionais, submetidos à diferentes torques de inserção

Abstract

The use of implants in the rehabilitation of edentulous patients revolutionized dentistry and brought great quality of life for these people. The search for an excellent primary stability, especially in cases of immediate loading, can induce the clinician to apply high insertion torque. The aim of this study was to evaluate the consequences of different insertion torque in the adaptation of prefabricated and laboratory modified abutments on two types of external hexagon implants (EH): conventional (CO) and internal torque (IT). Fifteen CO and fifteen IT implants, all of them HE, were divided into six groups with five implants each: G1 e G2 - CO and IT Implants, respectively, that did not undergo insertion torque;G3 e G4 - CO and IT Implants, respectively, submitted to insertion torque of 40N/cm2; G5 e G6 - CO and IT Implants, respectively, submitted to insertion torque of 80N/cm2. These implants were inserted perpendicularly into blocks of acrylic resin to compose the specimens. Prefabricated abutments were screwed to the specimens and this set was then taken under an optical microscope to measure the vertical misfit at the implant-abutment interface. Then these abutments were removed and the process repeated with castable anti-rotational UCLA abutments, cast in NiCr alloy. The prefabricated abutments did not show significant misfit in all groups tested (0,36 ±0,04μm). The UCLA abutments showed greater misfit than the prefabricated ones (p <0.05) with similar misfits in all groups (20,72±3,5μm) except in the G6 group (93,84±4,38μm) differing significantly from the others. According to the results, the application of 80N/cm2insertion torque on EH CO implants detrimentally interfered in the adaptation of UCLA abutments, this combination may produce prosthetic complications when applied clinically.