universidade de são paulo - Faculdade de Odontologia - Unesp

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(smooth or roughened). All negative controls exhibited no metabolic activity (data
not shown).
Table 1 shows the means and standard deviations of contact angle and the
results of Tukey post hoc tests. It can be seen that there was significant change in
the mean contact angle after 48 hours of immersion in water for all groups
evaluated, with the exception of the control group, in which no significant
difference was found. In control group, there was significant difference between
the mean contact angle of smooth and roughened surfaces, regardless the time of
measurement. Similar result was observed in group ArSF 6 /70 W only in the 48
hours period.
Roughness values of all groups evaluated are presented in Table 2. There
were no significant differences among the groups in each investing technique. For
all groups, the mean roughness values of the specimens processed against stone
were higher than those of the specimens processed against glass.
XPS analysis demonstrated the incorporation of fluorine into the surface of
the specimens of ArSF 6 /70 group. Figure 2 shows the signals assigned to CF 2 and
CF 3 moieties and the envelope curve, which represents the total F(1s) area.
Discussion
The initial attachment of Candida albicans on the mucosal surface of the
denture is essential in the colonization and development of denture stomatitis.
Since many factors may influence the initial adherence of yeasts to acrylic
surfaces, such as attractive hydrophobic interactions and repulsive electrostatic