universidade de são paulo - Faculdade de Odontologia - Unesp

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average was calculated. Specimens were then stored at room temperature in sterile
distilled water for 48 h to release any residual monomer [10]. Afterwards, the
contact angles of each specimen were again measured.
Saliva Collection
Unstimulated whole human saliva was collected from fifteen healthy adult
volunteers. The saliva was expectorated into sterile 50 ml Falcon tubes on ice,
pooled and clarified by centrifugation at 10,000 g for 5 min at 4 ºC [10]. The
saliva was prepared at 50% (vol/vol) in sterile PBS [25]. The resulting saliva was
immediately stored at -70 ºC until use. The study was approved by the Ethics
Committee of Araraquara Dental School (027/2007), and all subjects volunteered
to participate and signed an informed consent form.
Adherence Assay
Candida albicans strain ATCC 90028 was used. Stock cultures were
maintained at -70 ºC. After recovery this was maintained on YEPD medium (1%
yeast extract, 2% peptone, 2% dextrose, 2% agar) stored at 4 – 6 ºC during the
experimental period. To prepare the yeast inoculum, a loopful of the stock culture
was streaked onto YEPD medium and incubated at 37 ºC for 48 h. Two loopfuls
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 100 mM
glucose. Candida suspensions were spectrophotometrically standardized to a
concentration of 1 x 10 7 cells/ml. Three ml of the standardized C. albicans cell