Análise in vitro da adaptação e da infiltração bacteriana na interface implante-conector em dois modelos de implantes extraorais

Resumo (EN)

The objectives of this study were to compare the implant-abutment interface adaptation and the bacterial infiltration between two extraoral implants models with different connection platforms types. Two implant models were used, one of the external hexagon platform type (HE), and another of the external conical type (CE). For adaptation analysis, the microgap between the implant and the abutment was evaluated with the assistance of scanning electron microscopy (SEM). Five sets of each model were submitted to SEM, totalling 120 measurements from different contact areas. For the bacterial infiltration analysis, eleven sets of each model of implant-abutment connections were immersed in Staphylococcus aureus (Sau) culture medium, and out of each group, one set was used as control. The sets were immersed for 24 hours, followed by material collection from two areas, the external hexagon surface and the implant’s internal chamber, with the aid of microbrushes. The collected material was harvested on Petri dishes filled with Mueller-Hinton Agar. The count of colony forming units (CFU) was carrid out 24 hours later. The SEM analysis results demonstrated that the mean values for the microgaps of group CE were statistically lower when compared to the ones found in group HE, according to the Mann-Whitney test results (p<0.0001). Regarding the bacterial infiltration, the statistical analysis showed differences between the medians of the group HE in relation to the group CE, which revealed that the amount of bacteria counted was significantly higher in the group HE (p <0.0001). With these results, it was possible to conclude that the extraoral implants from group CE presented better adaptation and greater sealing properties, which was evidenced by the lower bacterial infiltration and by the smaller abutment-implant microgap size when compared to the values found within group HE.