Bacterial adhesion of Actinobacillus actinomycetemcomitans serotypes to titanium implants: SEM evaluation. A preliminary report

Background: In this study, the adherence ability of Actinobacillus actinomy cetemcomitans serotypes to titanium implant surfaces was evaluated to demon strate if any selective adherence occurs according to the serotypes of the microorganism. Methods: The study material included 3 reference strains of A. actinomycete mcomitans serotypes a, b, and c (ATCC 29523, ATCC 43718, ATCC 33384) and 2 clinical isolates of A. actinomycetemcomitans serotypes d and e (IDH 781, I DH 1705), together with commercially available titanium blade implants. For each strain, bacterial suspensions with identical concentrations (5 x 10(7 ) cells/ml) were prepared and 0.5 ml of each was added on to the implant su rfaces,which had been precoated with glycine-bovine serum albumin (BSA). Af ter incubation at 37 degrees C for 60 minutes in 5% CO2 in air, the implant s with attached bacteria were prepared for scanning electron microscopic (S EM) observations. Bacterial adhesion was quantified on the textured body su rfaces of the implants, and results were statistically analyzed with analys is of variance followed by Duncan's test. The surface ultrastructure of the bacterial cells was also evaluated descriptively. Results: The tested strains adhered to implant surfaces in different quanti ties. Serotype a (ATCC 29523) showed the highest adherence affinity (statis tically significant, P <0.01). When compared with each other, serotypes b, c, and d (ATCC 43718, ATCC 33384, and IDH 781) attached equally well, where as serotype e (IDH 1705) had a statistically significant low adherence capa bility. Conclusions: It is suggested that in vitro A. actinomycetemcomitans adhesio n to implant surfaces is strain dependent.