Microleakage at the abutment-implant interface of osseointegrated implants: A comparative study

Microleakage can occur at the abutment-implant (A-l) interface in osseointe grated implants and may cause malodor and inflammation of peri-implant tiss ues. The degree of microleakage at the A-I interface of 5 implant systems w as comparatively assessed at varying closing torques. Using colored tracing probes driven by a 2-atm pressure system, the interface microleakage of Br anemark, Sulzer Calcitek, 3i, ITI, and Steri-Oss implants was determined sp ectrophotometrically. Microleakage through the A-I interface occurred in al l systems, with variability between systems, samples, and closing torques. As closing torque increased from 10 Ncm to 20 Ncm to manufacturers' recomme nded closing torques, microleakage decreased significantly (P <.005) for al l systems. Analysis of variance showed significant interaction between clos ing torques and the time course of microleakage, and between systems and th e time course of microleakage (P <.001). The results indicate that fluids a nd small molecules are capable of passing through the interface of all the A-I assemblies studied. Presumably in an in situ situation, fluids containi ng bacterial byproducts and nutrients required for bacterial growth may pas s through the interface gap, contributing in part to clinically observed ma lodor and peri-implantitis.