OBJECTIVE

In implant rehabilitation, a microspace is created at the abutment-implant interface (AII). Previous research has
shown that oral microbiome can proliferate in this microspace and affect periimplant tissues, causing inflammation
in peri-implant tissues. Preventing microbial leakages through the AII is therefore an important goal in implantology.
The objective of this study was to determine the presence of marginal bacterial microleakage at the AII according
to the torque applied to the prosthetic implant in vitro.

MATERIALS AND METHODS

Twenty-five Ticare Inhex internal conical implants (MG Mozo-Grau, Valladolid, España) were connected to a prosthetic abutment using torques of <10, 10, 20, 30, and 30 N and then sealed. The samples were submitted to cycles
of occlusal loads and thermocycling, then one sample of each group was observed by micro-CT, while the rest were
mounted on devices according to the bacterial leakage model with Porphyromonas gingivalis.

RESULTS

Bacterial leakage was observed only in the <10 and 10 N torque samples, and the same groups presented poor
abutment/implant adjustment as determined by micro-CT.

CONCLUSION

The different torques applied to the abutment-implant system condition the bacterial leakage at the implant interface. No microleakage was observed at 20 and 30 N.