In vitro Candida albicans biofilm formation on different titanium surface topographies

Abstract

Objectives

To investigate if differences in titanium implant surface topography influence Candida albicans biofilm formation.

Materials and Methods

Titanium discs were prepared and characterized using a profilometer: Group A (R_a 0.15 µm, smooth), Group B (R_a 0.64 µm, minimally rough) and Group C (R_a 1.3 µm, moderately rough). Contact angle and surface free energy (SFE) were determined for each group. Non-preconditioned titanium discs were incubated with C. albicans for 24 h. In additional experiments, the titanium discs were initially coated with human saliva, bovine serum albumin or phosphate-buffered saline for 2 h before incubation with C. albicans for 24 h. The amount of fungal biofilm formation was quantified using a colorimetric assay.

Results

C. albicans biofilm formation was significantly lower (p < 0.05) on the minimally rough titanium surface compared to smooth and moderately rough surfaces. The titanium surface displaying the lowest SFE (Group B) was associated with significantly lower (p < 0.05) C. albicans biofilm formation than the other two groups. Salivary coating resulted in greater adherence of C. albicans with increased surface roughness.

Conclusions

The minimally rough titanium discs displayed lowest SFE compared to smooth and moderately rough surfaces and showed the least C. albicans biofilm formation. This study demonstrated that C. albicans biofilm formation increased in a SFE-dependent manner. These findings suggest that SFE might be a more explanatory factor for C. albicans biofilm formation on titanium surfaces than roughness. The presence of a pellicle coating may negate the impact of SFE on C. albicans biofilm formation on titanium surfaces.

Keywords:

• Dental implants
• Candida albicans
• titanium
• surface roughness
• surface tension

Acknowledgments

The authors are grateful for Dr. Lina Stangvaltaite-Mouhat (Department for Clinical Dentistry, UiT the Arctic University of Norway, Tromsø and Oral Health Centre of Expertise in Eastern Norway, Oslo, Norway.) for careful reading of the manuscript and for her insightful suggestions.

The publication charges for this article have been funded by a grant from the publication fund of UiT The Arctic University of Norway.

Ethical approval and informed consent

In this study, the use of human saliva was approved by the University of Sheffield Research Ethics Committee. (University of Sheffield Research Ethics Committee approval number 003166).

Author contributions

All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Mathieu Mouhat, Robert Moorehead and Craig Murdoch. The first draft of the manuscript was written by Mathieu Mouhat and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

Disclosure statement

The authors declare that they have no conflict of interest.

Data availability statement

The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.