universidade de são paulo - Faculdade de Odontologia - Unesp

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absorbance values obtained after preconditioning with saliva were higher than
those of the control group. The two methods used in the present study to
determine the adhesion of C. albicans to the denture base resin are based on
different principles. In the crystal violet staining method, the stained cells are
quantified by counting in selected fields of the substrate 15,18,19,23,24 , whereas in the
XTT assay, the metabolic activity of all viable cells is measured 1,11,21,26 . It is
worth noting that most of the studies that have found an increase in Candida
albicans colonization on denture materials after pre-incubation with saliva have
used tests of monitoring the pH of the growth medium, adenosine triphosphate
(ATP) analysis and XTT assay 6,7,8,9,10 . Conversely, when the adherent cells were
quantified by microscopy or by colony forming unit (UFC) counts, the majority of
the studies on Candida albicans colonization on denture materials observed an
absence of significant effect of saliva 12,13,14 or reduced adhesion 14,15,16,17,18,19 .
Hence, it is suggested that the controversial results regarding the role of saliva on
the adhesion of Candida to denture materials may at least partially be accounted
for by different adhesion assays used. This highlight that the effect of saliva on
the adhesion and biofilm development of Candida should not be studied by a
single quantification method.
The divergent results among studies may also be attributable to the various
materials that have been used as substrates, among them acrylic surfaces
9,10,13,14,15,16,17,18,19,22 , denture reline materials 6,7,8,12,17,19 , maxillofacial polymeric
materials 5,9 and polystyrene 11,21 . It has been reported that the exposed chemical
groups of the solid surface probably play the most important role in determining