Objectives: To detect any differences in the propensity of individual saliv
a to cause in vitro staining by chlorhexidine and tea.
Methods: Unstimulated human saliva was collected on a daily basis and used
to coat optically clear Perspex specimens. Specimens were subjected to the
original chlorhexidine/tea staining model described by Prayitno and Addy (J
ournal of Periodontal Research 1979;14:397-402), and cycles repeated until
a maximum optical density of two was reached.
Results: Stain development increased incrementally with increasing cycles.
Differences in chlorhexidine/tea staining between subjects were obvious by
cycle 3 where the lowest 'stainer' had 56% less stain than the highest 'sta
iner'. Highly significant differences between subjects were seen during sta
ining cycles 3-6. but not at cycles 7 and 8
Conclusions: In vitro stain formation using saliva from different individua
ls occurred at differing rates when all other variables were standardised.
The properties of saliva accounting for this are still unknown, and warrant
further study. (C) 2001 Elsevier Science Ltd. All rights reserved.