universidade de são paulo - Faculdade de Odontologia - Unesp

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of this young culture were transferred to 20 mL of yeast nitrogen base (YNB)
medium with 50 mM glucose and incubated at 37 ºC for 24 h. Cells of the
resultant culture were harvested, washed twice with phosphate-buffered saline
(PBS, pH 7.2) at 5000 g for 5 min and resuspended in YNB with 100mM glucose.
Candida suspensions were spectrophotometrically standardized to a concentration
of 1 x 10 7 cells/mL. Three mL of the standardized C. albicans cell suspension was
added to each well containing the specimen. The cells were left to adhere for 90
min at 37 ºC 28 . The non-adherent cells were removed from the specimen by
gently washing twice with 3 ml PBS. For all experimental conditions, the negative
controls were acrylic specimens to which no cells were added. All experiments
were performed in triplicate on three independent occasions.
Preconditioning with Saliva
To investigate the effect of the saliva on candidal adhesion to the denture
acrylic resin, half of the specimens from each group (9 rough and 9 smooth) were
incubated into the 12-well microtiter plates and coated with 3 mL of prepared
saliva for 30 min at room temperature prior to the adhesion assay.
Measurement of Adherent C. albicans
To estimate the number of adherent yeasts, 9 specimens from each
experimental condition were evaluated by XTT reduction assay, which evaluates
cell viability of the adherent cells. XTT (Sigma, MO, USA) was prepared in
ultrapure water at a final concentration of 1mg/mL. The solution was filter
sterilized and stored at -70 ºC until use. Menadione (Sigma, MO, USA) solution