Saliva

[HartA at agresearch.cri.nz]

I want to collect human saliva samples. I vaguely recall that it is possible 
to get absorbent pads that can be sucked/ chewed and then removed from the 
subjects mouth. Does anyone know of a source of these? Would the cylindrical 
pads that dentists use to keep their patient's teeth dry be suitable?

Thanks,
                  Alan Hart