Effectiveness of GapSeal on Microgap and Microleakage at Internal-Hexagon Implant Platform after Cyclic Loading

Microgap found in implant-abutment connection is still one of the main problems that may lead to mechanical and biological failure and inflammation around implants. This study aimed to evaluate the effect of GapSeal on microgap and microleakage between fixture and abutment in internal hex connections. The experiment was performed using 12 implants to check the efficacy of sealing agent at the IAI. The implants were divided into 2 groups of 6 implants each: a group that used no sealing agent at the IAI and a group that used GapSeal at the IAI. Each sample mounted in the acrylic polymerized resin. GapSeal was applied between the fixture and abutment then abutments were assembled using a torque of 30N by digital torque meter. Then cyclic load was applied with the force of 80N and frequency of 1 Hz on the longitudinal axis of each sample. After 500000 cycles, for assessment of microleakage methylene blue solution was used. All set of fixture-abutment (case and control) immersed in the solution and all samples were placed in the incubator (37◦c) for 24 hour. Then the implant-abutments were cross sectioned longitudinally with cutting machine (figure 2) then micro-leakage and microgap were measured by Scanning electron microscope (×200) in the 3 points in each half circle. Finally data was evaluated by t-test. The mean microgap was 0.99±0.39 for GapSeal group that was significantly lower (P<0.000) than that of control group (3.04±0.54).
Also, results showed microleakage in all samples of control group whereas none of the samples of Gapseal group had microleakage. GapSeal caused less microgap and microleakage in implant-abutment interface.