Bioactive Spheres: The Way of Treating Dentin Hypersensitivity.

Sealing exposed dental tubules is the most effective and long-term way to relieve the pain induced by dental sensitivity. A bioactive hollow sphere (strontium substituted calcium phosphate) was synthesized and added in toothpaste to study its effect on dental hypersensitivity via tooth tubules occlusion and mineralization. The size of spheres is perfect for penetrating into dental tubules, reaching to 20 μm into the tubules. The exposed dental tubules were occluded by spheres and new apatite layer after 3 days brushing. The spheres attached to the surface of dentin and the mineralized surface contained two layers, a porous layer followed by a dense apatite layer. The porous layer can be dissolved in an acidic solution, but the following dense layer could be kept even after soaking in an acid solution. In conclusion, Sr-substituted calcium phosphate spheres could be a good candidate for at-home treatment of dental hypersensitivity.