C.albicans adherence on silicone-elastomers after saliva and nasal secretion exposure

Objectives: The surfaces of maxillo-facial prostheses exposed to the soft tissues may interact with saliva and nasal secretion. These body fluids lead to colonization of microorganisms on their surfaces leading to their degradation. This study investigated C. albicans adhesion to commercial maxillo-facial silicone elastomers with different polymerization processes. Methods: Maxillo-facial silicone materials (N=144) (10x10x2 mm), were processed differently, namely heat-temperature-vulcanized (HTV) (VerSiTal, VST-50F, USA), room-temperature-vulcanized (RTV) (VST-50, USA), and auto-polymerized (AP) (VST-30, USA) were studied. Materials were incubated in 1.5 ml artificial saliva or nasal secretion, contaminated with C. albicans cells (set to 0.5 OD, 540 nm, in advance). The specimens were randomly divided into two subgroups and contaminated with either artificial saliva or nasal secretion for 2 h. Candida assays and adherence assays were made by inoculating C. albicans into Mueller Hinton Broth, Fluka® added 500 mMol sucrose overnight. After fixation, all of materials were stained by using sterilized Methylene Blue stain (Merck®) and evaluated under light microscope (x40). For each material, 15 different areas (mm2) were counted. Results: Material type showed a significant influence on C. albicans adherence (p<0.05) (Tukey HSD, Dunnett). While AP material showed the most C. albicans after both saliva and nasal secretion (101.775 and 53.475, respectively) (p<.05) than other materials, RTV had the least colonization in both media (9.777 and 5.575, respectively). Conclusion: Among the tested materials room-temperature-vulcanized silicone resulted in more dense and better surface properties resulting in less C. albicans adherence.