On horsehair
Animal hair was the bristle of record for centuries. What nylon changed in 1938, and what it did not.
For most of the toothbrush's history, the bristle was hair. Brushes of bone and boar bristle were made in China long before Europe took them up; by 1780 they were being manufactured in England, the hair imported by the barrel. Horsehair sat beside boar in that trade as the softer option — mane hair, finer and kinder than hog bristle.
On 24 February 1938, DuPont began commercial production of the first nylon-bristle brush. Nylon was cheaper, uniform, and it dried fast. Within a generation, hair was gone from the bathroom.
What softness buys
The dental literature is consistent on one point: stiffer bristles remove somewhat more plaque, and softer bristles do measurably less harm to gums. A 2019 systematic review in the International Dental Journal found soft and extra-soft brushes safer for oral soft tissue; a 2021 meta-analysis confirmed the trade — medium and hard filaments clean interproximal surfaces better, at the price of abrasion and recession risk.
Horsehair sits at the soft end of that spectrum. It asks a little more of your technique — two unhurried minutes rather than thirty seconds of force — and gives your gums a longer life in return.
The honest trade
Hair holds more water than nylon. That is why nylon won in 1938, and it is why the care instruction on every REIN brush is not decoration: rinse well, shake out, dry upright with the head free. A horsehair brush kept in a dark cup of water is a poor idea. Given air, it dries, and it serves its three months as any brush should.
- Ranzan N, Muniz FWMG, Rösing CK. Are bristle stiffness and bristle end-shape related to adverse effects on soft tissues during toothbrushing? A systematic review. International Dental Journal. 2019;69(1):25–32. Source →
- Anti-plaque and anti-gingivitis efficacy of different bristle stiffness and end-shape toothbrushes on interproximal surfaces: a systematic review with meta-analysis. Journal of Evidence-Based Dental Practice. 2021. Source →
- Hagley Museum and Library. On this date in 1938 — DuPont's Miracle Tuft toothbrush, the first commercial use of nylon. Source →
- Virtual Dental Museum, University of the Pacific. Different strokes for different folks: a history of the toothbrush. Source →