Candida albicans colonization on thermal cycled maxillofacial polymeric materials in vitro

In the present study, the colonization of a single isolate of Candida albicans on saliva-, serum-coated or protein free (uncoated), thermocycled (4-70 degrees C for 1 min, respectively; 0, 1000 and 10 000 times) 15 commercial maxillofacial materials were investigated, by adenosine triphosphate (ATP) analysis. In the case of control specimens (not thermocycled and uncoated), the fungal colonization appeared to depend upon the type of commercial products used. Thus, the lowest colonization was observed with additional silicone materials, soft acrylic liners with visible light curing, except for one product, whereas visible light curing liners comprising of single paste or single gel exhibited the highest colonization capacity, and cold cured acrylic liners exhibited the intermediate. However, the fungal colonization on the materials was significantly promoted both by thermal cycling (ANOVA; P < 0.01) and a layer of protein coating (saliva, P < 0.01; serum, P < 0.01). When the inter-relation between the fungal colonization and the surface hydrophobicity of the materials were analysed, fungal colonization on 1000- and 10 000-thermocycled materials correlated well with the contact angles of the materials (Student's t-test, P < 0.01), being consistent with the thermodynamic theory. These results, taken together, suggest that the ageing of the materials and the biological fluids of the host promote yeast colonization on maxillofacial materials.