universidade de são paulo - Faculdade de Odontologia - Unesp

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had resulted in greater bacterial adhesion, higher increases in roughness
diminished adherence. Results such as these indicate the need for further studies
that evaluate the effect of surface roughness on the adhesion of Candida albicans,
using resin samples with different pre-established roughness values that cover a
wide range of variation. In any event, the results observed in the present study are
in agreement with those of recent researches [10, 27, 32-34] in which no
significant influence of roughness on the adherence of Candida albicans was
observed.
The surface modifications made in the samples of the present study
include the reduction of surface hydrophobicity, obtained by means of the plasma
treatments with AAt/130 W, ArO 2 /70 W, Ar/50 W, as well as the incorporation of
fluoride into the resin surface, achieved in the group treated with ArSF 6 /70 W.
The groups AAt/130 W, ArO 2 /70 W and Ar/50 W presented a decrease in the
angles of contact values, indicating that immediately after the treatments, the
surfaces became more hydrophilic. These results could be attributed to the fact
that during plasma treatments, inelastic collisions involving energy electrons from
the discharge and species from the polymer surface create free radicals, which in
turn react chemically with species from the polymer or atmospheric air,
incorporating hydrophilic groups into the polymeric surfaces [18]. This
incorporation of hydrophilic groups increases the surface energy, consequently
diminishing the angles of contact values [18].
Similar to the observations made by other authors [22, 23], plasma
treatment with ArSF 6 /70 W increased the angle of contact of the samples. This