Restoring mineral to the teeth ~ Medical Hydroxyapatite Movie ~
Learn about Sangi's original nano-hydroxyapatite remineralizing technology and its oral care functions;

Copyright © 2016 SANGI CO.,LTD. All Rights Reserved.

Model of Action on the Teeth


  • adhere to and help remove bacteria & plaque
  • fill and repair microscopic surface fissures
  • remineralize subsurface demineralized areas (incipient caries)
  • supplement salivary mineral
  • occlude exposed dentinal tubules

Consumer Benefits

  • protection against caries
  • enhanced whiteness and gloss
  • smoother enamel
  • greater resistance to plaque and stains
  • relief from hypersensitivity

Remineralization Natural Tooth Repair

Remineralization Natural Tooth Repair Sangi’s idea in developing the first nano-hydroxyapatite remineralizing toothpaste was to support a naturally occurring function – the restorative role of saliva – in the mouth.
Demineralization and remineralization of tooth enamel take place constantly. The tooth surface is easily colonized by bacteria to form dental plaque, especially in minute fissures or spaces between the teeth where a toothbrush cannot reach. Enamel is made up of closely packed hydroxyapatite rods, separated by tiny channels about 50 nanometers wide. Acids produced by plaque bacteria seep into these channels and can dissolve the rods, causing the enamel to become demineralized.

Saliva plays a protective role, by neutralizing acids caused by plaque bacteria, and by providing calcium and phosphate ions – the building blocks of hydroxyapatite – which diffuse back into the enamel to restore lost mineral, so that the enamel becomes remineralized.

If demineralization and remineralization balance each other at the tooth surface, no net loss of mineral occurs. But conditions such as excess plaque, inadequate saliva flow, or heavy intake of acidic foods and beverages can tip the balance in favor or demineralization, so that a cavity – dental caries – may result.
However in its early stages, if sufficient mineral is provided, demineralization (incipient caries or ‘white spot’ lesions) can be reversed.
Nano supplements this natural supply of mineral by the saliva.

Anticaries Functions Mode of Action of nano<mHAP>

Three functions of nano were recognized by Japanese health authorities in approving it as an active anticaries ingredient in 1993, namely :

① Adhesion to and Removal of Plaque

<mHAP> has a strong propensity to bind with protein, and adheres to bacteria and plaque fragments during brushing, facilitating their removal on rinsing from the mouth. This feature is enhanced by <mHAP>’s nanoparticle size, which increases the surface area to which proteins attach.

&#9312; Adhesion to and Removal of Plaque

&#9312; Adhesion to and Removal of Plaque

<mHAP> nanoparticles bind to S. mutans bacteria
(Electron Micrograph)

② Filling of Microscopic Surface Fissures

<mHAP> also acts as a filler, repairing minute pits and fissures in the enamel surface. This function, also enhanced by its nano size, results in smoother, glossier enamel, with fewer sites likely to harbor plaque and stains

&#9313;	 Filling of Microscopic Surface Fissures

&#9313;	 Filling of Microscopic Surface Fissures

Enamel surface roughness (left) before and (right) after treatment with nano<mHAP> toothpaste.
RA=average surface roughness (nm)
(Scanning Probe Micrograph(SPM), Sangi Central Research Laboratory)

③ Remineralization of Subsurface Demineralized Areas (Incipient Caries)

< mHAP>:nanoparticles supplement the supply of mineral from saliva, remineralizing subsurface demineralized areas of the enamel (‘white spot’ lesions or incipient caries), and restoring mineral density and translucency to enhance the whiteness of the teeth.

&#9314;	 Remineralization of Subsurface Demineralized Areas (Incipient Caries)

&#9314;	 Remineralization of Subsurface Demineralized Areas (Incipient Caries)

Subsurface demineralized area (left) before and (right) after treatment with Nano <mHAP> toothpaste
(Contact Microradiogram, Sangi Central Research Laboratory)

By helping to remove plaque, and restoring smoothness and mineral density to both surface and subsurface enamel, nanoparticles not only protect against decay, but restore translucency and gloss, contributing to both the health and natural beautyof the teeth.

Antihypersensitivity Dentinal Tubular Occlusion

Sangi's nano-hydroxyapatite toothpaste, in both in vitro and in situ tests, has been shown to occlude exposed dentinal tubules and create a fine hydroxyapatite coating over the exposed dentinal surface. Preliminary clinical studies and consumer trials indicate that it is effective in alleviating dentinal hypersensitivity.

Antihypersensitivity Dentinal Tubular Occlusion

Exposed dentinal surface and tubules, (a) before and
(b) (c) after treatment with Sangi's nano-hydroxyapatite toothpaste

Antihypersensitivity Dentinal Tubular Occlusion

Cross-section of (b), showing tubular occlusion and surface coating by Sangi's nano-hydroxyapatite

(K.Ohta et al. Occlusion of Dentinal Tubules by Nano-Hydroxyapatite)
(Amaechi et al, Evaluation of Nano-hydroxyapatite-containing Toothpaste for Occluding Dentin Tubules )

Copyright © 2019 SANGI CO.,LTD. All Rights Reserved.