Listerine label:

The label says Listerine is "as effective as floss".

But it also tells me to "floss daily".  Why should I floss daily if Listerine is as effective as floss?

Yes, these are the things that cross my mind from time to time.

RELATED:  Speaking of dentistry, check out this hellish dental instrument from 1939:

Device Takes Measure of the Teeth

WITH the aid of the “gnathograph,” an instrument as mouth-filling as its name, a dentist’s patients may now be assured of a perfect fit for artificial teeth. Fitted to the jaws as shown above, the new device registers the arrangement of the teeth and the direction of the “bite,” to guide the dentist in straightening teeth or fitting inlays, crowns, bridges, and plates.