Nanomaterials in preventive dentistry

Journal name:
Nature Nanotechnology
Year published:
Published online


The prevention of tooth decay and the treatment of lesions and cavities are ongoing challenges in dentistry. In recent years, biomimetic approaches have been used to develop nanomaterials for inclusion in a variety of oral health-care products. Examples include liquids and pastes that contain nano-apatites for biofilm management at the tooth surface, and products that contain nanomaterials for the remineralization of early submicrometre-sized enamel lesions. However, the treatment of larger visible cavities with nanomaterials is still at the research stage. Here, we review progress in the development of nanomaterials for different applications in preventive dentistry and research, including clinical trials.

At a glance


  1. Bioadhesion and biofilm management in the oral cavity.
    Figure 1: Bioadhesion and biofilm management in the oral cavity.

    a, Bioadhesion in the oral cavity. Proteins interact with the enamel surface to form a proteinaceous pellicle layer. Bacteria adhere to this conditioning film through calcium bridges and specific adhesin–receptor interactions (purple and red). Bacteria are surrounded by an extracellular matrix of water-insoluble glucans, and they communicate through quorum sensing (arrows). b, Cross-section of a human molar tooth showing the enamel, dentine and pulp chamber. c, Easy-to-clean nanocomposite surface coating. The low-surface-free-energy coating (blue) causes poor protein–protein binding. Shear forces in the mouth (yellow arrow) can easily detach the outer layer of the pellicle and bacterial biofilm from the surface. d, CPP–ACP inhibits bacterial adhesion and oral biofilm formation. CPP attaches to the pellicle and limits bacterial adhesion. It competes with calcium for plaque–calcium binding sites (I), and decreases the amount of calcium bridging the pellicle and bacteria, and between the bacterial cells. Specific receptor molecules (red) in the pellicle layer and on the bacterial surfaces (brown) are blocked, further reducing adhesion and co-adhesion (II). This affects the viability of the bacteria (III).

  2. Early stages of tooth decay caused by bacterial biofilm.
    Figure 2: Early stages of tooth decay caused by bacterial biofilm.

    Bacteria metabolize sugar and other carbohydrates to produce lactate (HL) and other acids that, in turn, dissociate to form H+ ions that demineralize the enamel beneath the surface of the tooth; calcium and phosphate are dissolved in the process. This is known as a white-spot lesion. Owing to reprecipitation, a pseudo-intact surface layer (red arrow) is observed on top of the body of the carious lesion in this early stage of tooth decay. This pseudo-intact layer is permeable to ions (indicated by white chevrons).

  3. Hierarchical structure of the dental enamel.
    Figure 3: Hierarchical structure of the dental enamel.

    Dental enamel is a masterpiece of bioceramics, containing structures at different hierarchical levels from the microscale down to the nanoscale. The enamel is composed of three-dimensionally organized nanosized hydroxyl apatite crystallites (a,b,d) that are arranged into micrometre-sized prisms (c,e). a, Atomic force microscope and b,c, scanning electron microscope images of the enamel surface. d, Transmission electron microscope and e, scanning electron microscope images of a cross-section of the enamel.

  4. Dental erosion caused by acidic beverages or food in the oral cavity.
    Figure 4: Dental erosion caused by acidic beverages or food in the oral cavity.

    Low pH, caused by acidic beverages or gastric juices (pH 1–4), destroys the enamel surface by partial and complete dissolution of the enamel crystallites, resulting in the release of Ca2+ and HPO42− ions. This loosens the microstructure of the enamel and hydroxyl apatite crystallites (pale blue) become demineralized, or are lost.


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  1. Clinic of Operative Dentistry, Periodontology and Preventive Dentistry, University Hospital, Saarland University, Building 73, D-66421 Homburg/Saar, Germany

    • Matthias Hannig
  2. Clinic of Conservative Dentistry, Faculty of Medicine 'Carl Gustav Carus', Technical University Dresden, Fetscherstr. 74, 01307 Dresden, Germany.

    • Christian Hannig

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