How Dental Floss Became a Thing in the First Place

5 minute read

Those regularly chided by their dentists got good news on Tuesday, as the U.S. government acknowledged something to which TIME had brought attention last year: there is little scientific evidence that flossing your teeth really makes a difference when it comes to cavities and gum disease.

But if we’ve all just been wasting minutes a day on flossing—which, let’s be honest, few people actually want to do—why did we start doing that in the first place?

Humans have surely been using string (among other tools) to dislodge food for as long as string has been around, but the modern idea of dental floss is only two centuries old. In 1819, Levi Spear Parmly of New Orleans published his book A Practical Guide to the Management of the Teeth, and in it he described an invention he is often credited with thinking up just a few years earlier:

To what then are the disorders of the teeth to be attributed? This is an interesting question ; and one whose solution escaped even the penetration of those celebrated physiologists, Hunter and Fox. I esteem it, indeed, a most fortunate circumstance, that my attention was so early and closely engaged by an enquiry of such general importance: and I can now assure my readers, that the result of my labours, founded on the successful
prosecution of a series of the most numerous and satisfactory experiments, few have had even an opportunity of making is, that the relics of what we eat or drink, (without regard to its quality) being allowed to accumulate, stagnate, and putrefy, either in the interstices of the teeth, as is most commonly the case, or else in those indentures on their surface, favourable for the lodgement of food, is universally the cause of their decay, and generally of most other disorders, to which they are exposed…

This is the true source of caries, or decay of the teeth, which the two late eminent writers before-mentioned, find so difficult to account for; and of which discovery I cannot help feeling a pride and pleasure in avowing myself the author; for I can, with confidence, assert, that if the teeth and gums are regularly cleaned with the dentifric apparatus, recommended by the author, no caries can possibly take place. This then is a simple and clear view of the subject, and the grand desideratum for retaining these important organs in a sound and healthy state, to the latest period of existence. The mode of cleaning the teeth, as usually performed, is to rub them with a brush and a preparation of tooth powder, or tinctures, (to which some great quality is ascribed;) but, in whatever way it is employed, the source of the evil still remains; for the interstices and irregularities of the teeth afford a lodgement for whatever is taken into the mouth ; and no contrivance hitherto discovered can, from these parts, remove the accumulation.

After much experience and reflection on the subject, I found it necessary to construct a dentifric apparatus, which is found to answer every purpose, and to obviate the defects in common practice. This apparatus consists of three parts, contained in a small case, with a dental mirror, fit for the toilet or the pocket.

The first part to be used is the brush. It is made hollow in the middle, to embrace every part of the teeth, except the interstices ; and thus, at one operation, the top, (a part hitherto entirely neglected) the outer and inner surfaces are completely freed from all extraneous matter. The second part is the dentifric polisher, for removing roughness, stains, &c. from the enamel, and restoring to the teeth their natural smoothness and colour. The third part is the waxed silken thread, which, though simple, is the most important. It is to be passed through the interstices of the teeth, between their necks and the arches of the gums, to dislodge that irritating matter which no brush can remove, and which is the real source of disease. With this apparatus, thus regularly and daily used, the teeth and gums will be preserved free from disease ; the use of powders, tinctures, &c. will be superseded ; and the breath will not be loaded with that putrid effluvium, which, besides its public annoyance, is the cause of numerous disorders. Indeed, were persons sufficiently attentive to cleanliness of the mouth, diseases of the teeth and gums might be prevented, without the necessity of any painful operation, which would contribute no less to the improvement of the features of the countenance, than to the promotion of general health and comfort. Having thus pointed out the simple and successful method of preserving the teeth and gums, and rendering the breath agreeable, we will now consider their treatment when in a diseased state, and rectify the practice of former dentists.

Furthermore, Parmly specified, “particular care [should be] taken to pass the waxed silk in the interstices, and round the necks of the teeth.”

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Within a century, Parmly’s idea had become dental common practice, with inventors working on improvements. When World War II hit American silk supplies hard, a new invention—nylon—stepped in, thanks in particular to a pioneering dentist names Charles C. Bass.

In June of 1910, a New York business had this to say to the readers of Practical Druggist and Pharmaceutical Review of Reviews: “You know the value of dental floss. No one realizes better than you that the constant use of it would save lots of tooth trouble.” Today, however, “the value of dental floss” is not so certain.

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