In the oral care sector, silica, thanks to its unique physical and chemical properties, has become a core component of mid- to high-end toothpastes. Its applications extend from basic cleaning to functional care, driving the toothpaste industry towards refined products.
As an abrasive, silica is key to cleaning effectiveness. Precipitated silica has an irregular porous structure, a Mohs hardness of approximately 5.5, and an abrasiveness value controllable between 50-150. It effectively removes plaque and pigments while minimizing tooth enamel wear. Its particle size can be precisely controlled to meet specific needs: whitening toothpastes use particles of 8-12μm for enhanced stain removal, while children's toothpastes maintain a smaller particle size to ensure the safety of primary teeth.
It also safeguards paste stability. Fumed silica, present as nano-sized spherical particles, has a high specific surface area, enabling both thickening and suspension functions. This prevents the sedimentation of active ingredients such as fluoride, while improving the paste's thixotropy, ensuring smooth extrusion and excellent formability. Its refractive index is close to that of glycerin and sorbitol, and it is the only abrasive used in transparent toothpaste.
Silica demonstrates significant potential in functional upgrades. Surface modification to load anti-allergenic ingredients, or the use of 3-4.5μm particles to block dentinal tubules, can alleviate tooth sensitivity. Highly dispersed products are suitable for electric toothbrushes, improving cleaning efficiency and taste. Combined with its strong chemical inertness and good compatibility with fluoride, silica has become a core component in toothpaste's multiple value propositions: cleaning, tooth protection, and functional care.