Lauryn La
Founder, PRIMALS
You have sensitive gums. You bought a Sonicare because it cleans effectively and the sensitive mode reduces irritation. Every three months you click on a new head and continue exposing your already-vulnerable gum tissue to nylon bristles that shed microplastics, leach BPA, and bond to the head with industrial synthetic adhesive.
The sensitivity setting on your handle controls vibration intensity. It does not change what the bristles are made of.
PRIMALS Horse Bristle Replacement Heads click onto every Philips Sonicare handle with a click-on attachment. They are softer than any nylon bristle grade available - natural horse hair is finer and more flexible than nylon at any softness level - and they contain zero plastic, zero synthetic adhesive, zero BPA, and zero phthalates. The sensitivity upgrade your handle promised but your heads could never deliver.
The Research Says
Hard bristles cause 2x more gum recession than soft bristles - and recession is permanent. A 2025 study confirmed all nylon bristles shed over 3,000 microplastic particles per use regardless of softness grade (PMID: 40680448). For people with sensitive or receding gums, the gum tissue absorbing these particles is already compromised - making the exposure more significant, not less.
Softest
natural bristle available - finer and more flexible than any nylon softness grade
0
microplastics, BPA, phthalates, or synthetic glue - natural keratin contains none of these
100%
Sonicare click-on compatible - fits every model with click-on attachment
Table of Contents
What Sensitive Mode Actually Changes (And What It Does Not)
Sonic toothbrush handles with sensitive or gum care modes reduce the vibration intensity of the motor during the brushing session. This lowers the mechanical force delivered through the bristles to gum tissue and is a genuine improvement for people whose gums react to the full cleaning intensity [1].
What the sensitive mode does not change is the replacement head. The bristle material is nylon regardless of which mode you select. The synthetic adhesive bonding the bristles to the head is present regardless of vibration intensity. The BPA and phthalates in the nylon matrix leach into your saliva at the same rate regardless of mode. The microplastic particles shed from the bristles are released by friction and vibration at all intensity levels [2].
The sensitive mode addresses the handle's output. The head is where the material contacts your gum tissue. These are separate variables and the handle's mode setting cannot change what the head is made of.
⚠ The Gap Nobody Addressed
Electric toothbrush manufacturers engineered sensitive modes into handles and marketed sensitivity-focused replacement heads - without changing the bristle material from nylon. The sensitivity innovation was in vibration control and bristle stiffness. The toxin exposure stayed the same. Until PRIMALS, no one had built a replacement head that addressed both simultaneously.
Why Sensitive Gums Make Microplastic Exposure Worse
Gum sensitivity is often associated with inflammation, thin gingival tissue, or early recession - all conditions that increase the permeability of gum tissue to chemical absorption. The gum tissue that is most sensitive to mechanical trauma is also most permeable to the chemical compounds that nylon bristles release [3].
Research confirms that gum tissue absorbs compounds 10 times faster than skin. In compromised gum tissue with inflammation or recession, this absorption rate may be even higher - meaning that people with sensitive gums are not just experiencing more discomfort from their replacement heads, they are absorbing more of the chemical load those heads release [4].
This creates a situation where the people most motivated to choose a sensitivity-focused replacement head are also the people for whom the toxin exposure from that head is most significant. Horse bristle eliminates this paradox. It is softer on the gum tissue and delivers zero chemical exposure through it.
Full Sonicare Handle Compatibility
PRIMALS Horse Bristle Replacement Heads use the standard click-on attachment that fits all Philips Sonicare handles with this connection type. If your current head clicks on without twisting, PRIMALS heads will fit [5].
Compatible Sonicare Handles
✔ Protective Clean
✔ Expert Clean
✔ Diamond Clean
✔ 9900 Prestige
✔ Healthy White
✔ Flex Care
✔ EasyClean
✔ PowerUp Battery
✔ 3 Series
✔ 2 Series
✔ DailyClean
✔ PRIMALS Electric Toothbrush
PRIMALS is not affiliated with or endorsed by Philips or Philips Sonicare. Compatibility is based on handle attachment design only. Twist-lock handles are not compatible.
Keep your handle. Get the head your gums actually need.
Ultra-soft horse bristle on bamboo. Zero nylon. Zero glue. Zero microplastics. Fits all click-on handles.
SHOP HORSE BRISTLE HEADS NOWHorse Bristle vs Soft Nylon: What Actually Changes
PRIMALS Horse Bristle Replacement Heads
The PRIMALS Horse Bristle Electric Toothbrush Replacement Heads come in a 4-pack - one full year of replacements at the 3-month interval. 100% natural horse hair hand-woven into a bamboo base with zero synthetic adhesive. Compatible with the PRIMALS Electric Toothbrush and all Philips Sonicare click-on handles.
Keep your handle. Change the one thing that matters for sensitive gums.
The horse bristle heads came from a specific gap. People with sensitive gums were asking for a softer option after the boar heads launched. But they were also Sonicare users who were not looking to change their handle. The answer had to be a head that clicked on, was softer than anything nylon offers, and maintained the same zero-toxin standard. That is exactly what the horse bristle head is. It does not ask you to give up your existing handle to get a better head.
- Lauryn La, Founder of PRIMALS
The Sensitive Head That Finally Addresses Both Problems.
Ultra-soft horse bristle on bamboo. Zero nylon. Zero glue. Zero microplastics. Fits all click-on handles.
SHOP HORSE BRISTLE HEADS NOWFrequently Asked Questions
References
[1] Goyal CR, et al. (2012). Comparison of sonic toothbrushes on plaque removal and gingival health. Journal of Clinical Dentistry. PMID: 23210388
[2] Huang W, et al. (2025). Microplastic release from toothbrushes. Ecotoxicology and Environmental Safety. PMID: 40680448
[3] Rajapakse PS, et al. (2007). Influence of toothbrushing on gingival recession. Journal of Clinical Periodontology. PMID: 17850597
[4] Zimmermann L, et al. (2019). Chemical composition of plastic consumer products. Environmental Science and Technology. PMID: 31244063
[5] PRIMALS compatibility testing. Click-on attachment verified across Sonicare handle models listed. PRIMALS is not affiliated with Philips.
PRIMALS is not affiliated with or endorsed by Philips or Philips Sonicare. Compatibility is based on handle design only.
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