On Wednesday, August 23, 2017 at 2:46:41 PM UTC-4, Bill Gill wrote:



Why?

Dental-floss is made of many small mono-filaments that are not twisted or woven. Once upon a time, it was made from silk which has a high strength-to-weight (and thickness) ratio, and actually could bio-degrade. As it was a once-use/often-used material, the short shelf-life of silk was not an issue - just the cost.

So, along came the bean-counters and decided to make it from either PTFE or Nylon. And flatten the fibers (still non-woven or twisted) so that they would be more likely to catch onto plaque, after all, the intended purpose of the stuff. Neither of these two materials degrades. Nylon is mildly toxic when burnt. PTFE is not only toxic, but even if heated up will kill birds, cats and other sensitive species, as well as cause birth-defects in amphibians (the fumes). So, trash-to-steam operations will convert PTFE PoC (products of combustion) into environmental toxins that normal filtration (for CO2, NOX and similar, and even limestone beds will not catch.

That is the environmental issue.

Now, the stuff, because it is non-woven/non-twisted, because the fibers are flattened, and so forth, will abrade the sheaves and shaft(s) over time, and also shred over time. Fine if on a shelf-queen that is never used, not so fine in a daily driver.

And, of course, waxed floss would start to slip in short order.

Those are the practical issues.

If one is in a McGyver-type situation, then desperate needs call for desperate measures. But when indulging in a hobby, such expedients are neither necessary nor very efficacious.

Lastly, recent, peer-reviewed studies have shown that flossing is, effectively, useless. Our dentist does not even give out the freebies anymore. And I have all my teeth, including all four wisdom teeth (straight) and I have not had a cavity since I was 14 - for the last 51 years.

Hope that helps.

Peter Wieck
Melrose Park, PA