universidade de são paulo - Faculdade de Odontologia - Unesp

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(positive charge) were more adherent due to repulsive forces between negatively
charged yeast cell and polymer surfaces 7 .
Since surface characteristics of substratum are important to Candida
adherence 3,6 , chemical modification of the surface charge of denture base acrylic
resins by copolymerization of methacrylic acid to methyl methacrylate 9;11 or
incorporation of phosphate groups in the monomer 10,12 have been proposed to
prevent denture stomatitis. Another approach is the application of coatings with or
without incorporation of antifungal medications to change the hydrophobicity or
discourage microbial attachment 11,13,14 . Although these methods have been
effective in reducing the adhesion of Candida albicans to the acrylic surfaces,
there are concerns regarding the biocompatibility and the physical properties of
these modified polymers 9,10-12
as well as long-term durability 11,13,14 . Glow
discharge plasma-based treatments have also been considered a potential method
for surface modification of polymeric materials in many fields 3 . In this technique,
a partially ionized gas is generated by an electrical discharge, and thus, a highly
reactive environment is created with species like electrons, ions and free radicals.
Besides time efficient process, another advantage of this technique is that it allows
surface alteration without inducing bulk modifications 15,16 , preserving the
mechanical and physical-chemistry properties of the original materials. Some
authors have demonstrated that the plasma treatment is an effective method to
improve the hydrophilicity 3,15,17 , modify the chemical composition of the surfaces
16,18 , and decrease bacterial attachment 19 . Plasma treatment also allows the
incorporation of fluorine-containing species to the material 20,21 , resulting in