Tunes FSM. " Microbiological analysis of the seal with industrial sealant on the microgaps in the different implant connections: in vitro study" [Thesis]. São Paulo: Universidade de São Paulo, Faculdade de Odontologia; 2018. Original version. The use of dental implants and prosthetic components have become very feasible resources to solve simple and complex cases in rehabilitation dentistry. However, the implant component junction may present problems, such as the presence of a microgap between these components parts.Therefore, several materials have been tested in an attempt to obstruct this space, with controversial results. The objective of this study was to evaluate in vitro the behavior of an anaerobic monocomponent adhesive (Loctite® 510, Henkel Ltda), high resistance and inert characteristics, in the microgap seal preventing bacterial passage from the external side to the inner side of the assembly. A total of 90 implants were used, with hexagonal external connection (n = 30), internal hexagonal connection (n = 30) and internal conical connection (n = 30) divided into Control Group (n = 45). Implants were opened in laminar flow cabinet and each unit received 3µl of sterile BHI internally. On each unit a specific prosthetic component was screwed in for each brand and with torques recommended by the manufacturers with digital torque wrench. The sets of Test also received a thin layer of adhesive that was applied with microbrush between the parts; and all units of the Control and Test groups were sealed with provisional obturator material in their most coronal portion. Each set was immersed in 75 µl of Enterococcus faecalis (ATCC-29212) in mini-tubes to the limit between the implant / prosthetic component junction. All samples were incubated in a bacteriological incubator for 7, 14 and 28 days at 37 o C before being reopened. After the proposed period, the internal contents of the implants were collected with sterile paper cones, diluted and seeded in Petri dishes, incubated for 48 hours. There was a significant difference between the test and control groups in the hexagonal external connection group at all times (Fischer and Chi-square test, p ≤ 0.05). The anaerobic adhesive tested works as a barrier, not allowing the migration of bacteria into the internal environment of the implant / prosthetic component assembly.