The interproximal toothbrush is an invention patented by Thomas F. Thornton in the early 1970’s and introduced commercially in 1975. ( our history )
Referring to the diagram below, Figure 1 section is a stiff nylon threader for guiding the strand between teeth and under fixed bridgework, crowns, and orthodontic appliances. Figure 2 is the patented filament brush section, which is comprised of 204 tiny nylon filaments that have been formed into coiled springs. These springs have the capability to be stretched out and then automatically with memory revert to their original coiled state.
To use the interproximal toothbrush, slip the floss section between and through the contract points at the crowns of the teeth. (Figure 1). Then brush between the teeth by pulling the large filament brush through the small interdental space between the gum line and the contact point (Figure 2). When pulled, the filament brush, which is spongy in nature, slips though the much smaller spaces by stretching the coiled springs to make them flatter and less bulky to allow passage.
The brush removes plaque as it squeezes between sides of teeth; the harder it is pulled, the smaller it gets. The brush automatically cleans under the gum line since it compresses the gum tissue and cleans the exposed tooth surface simultaneously.
The brush reverts back to its original size for repeat usage after passing through an interdental space. This memory characteristic is incorporated into the filament springs by partially melting or softening the filaments with heat and then forming into springs, loops and curves before rapid cooling. This permanently locks in the new coiled and coiled configurations. Unless softened by heat and stretched out, the filament springs have a permanent memory as springs or loops and will not change regardless of repeated stretching and flattening.
The brush is unitary with the floss section and threader in that the filaments are continuous and run the length of the interproximal toothbrush. In the floss and threader are straight and parallel. In the brush, the filaments have been exploded into coils,loops and curves. These deformed and commingled filaments become flatter and more linear with an elongation force from either the floss or threader. Consequently, the brush diameter is reduced to allow easier passage between tight teeth and smaller embrasures.
The threader is used to enter the filament brush section into an interdental space from the side under a fixed area. It is then pulled utilizing the floss-and-brush technique. This allows for cleaning areas under fixed bridgework, crowns, and orthodontic appliances where there is no contact point or other entrance point.
The interproximal toothbrush is highly effective (see clinical study) in the removal of plague and food particles from hard to reach interproximal spaces. This capability results in greatly improved gum health.
The sales of over 10 (ten) billion pieces over the 35-year span from 1975 introduction to the present were generated by the health benefit afforded with use of the product.
Dentists in particular noticed improved gum health with usage and therefore started recommending the product to more patients. Patients in turn noticed their gums becoming more healthy and robust, which reduced tooth loss and other oral inflammation problems. The benefits meant that patients became lifetime users and additional new users provided long-term incremental growth in sales.
Mr. Thornton believes the interproximal toothbrush still would not be in existence if he had not invented it. First, the concept of marketing a variable diameter dental floss with larger diameter segments was a major marketing problem to overcome since dental professionals and patients alike were afraid of injury. Approximately 60% of dental professionals were initially skeptical and rejected the product. These naysayer’s objections were eventually overcome by salesman- ship, trial-and-error usage, and by clinical dental studies which showed that the gums become tougher and healthier when exercised. Approximately 40% of the dental professionals immediately recognized the benefits of the products and enthusiastically promoted the products and made purchases.
Secondly, the invention of the filament brush was an unusually original and probably not duplicable.