Adhesion of Candida Albicans to Dental Implant Surfaces

Objectives: Dental implant materials may be considered as a potential reservoir for the infection with Candida albicans. Thus, the aim of this in vitro study was to investigate the initial adhesion of Candida albicans to different titanium and zirconia implant surfaces.

Methods: Standardized specimens (diameter 5 mm, height 1 mm) of one zirconia and three titanium implant surfaces (all provided by Friadent, Mannheim, G) were analyzed. Peak-to-valley surface roughness (R_a) and surface free energy were determined. Specimens were incubated either with phosphate buffered saline (PBS) or human whole saliva for 2 h at 37°C, and were subsequently incubated with Candida albicans ATCC 10231 suspension for 2.5 h at 37°C. Adherent yeast cells were quantified using a bioluminometric assay. Medians and 25/75 percentiles were calculated, and statistical analysis was performed using the Kruskal-Wallis test (a=.05) and the Bonferroni-adjusted Mann-Whitney U-test for pair-wise comparisons (adjusted a=.0083).

Results:  

Data indicated significantly higher surface roughness for SBT and SBAET than for MT and ZC; for surface free energy, significantly higher values were found for SBT than for MT, SBAET, and ZC. For both uncoated and saliva-coated specimens, significant differences in relative luminescence intensities were found, indicating differences in Candida albicans adhesion; SBT showed significantly lowest relative luminescence intensities in both cases.

Conclusions: ZC showed no reduced potential to adhere Candida albicans in comparison to titanium surfaces; the influence of surface free energy on initial fungal adhesion to implant surfaces appears to be more important than the influence of surface roughness.