**5. Dental adhesives**

The primary function of dental adhesives is affixing to the tooth surface or to the elements included in the oral materials such as dentures or dental bridges used in order to restore or to reconstruct a tooth [37].

As in the case of dental prostheses based on poly(methyl methacrylate), dental adhesives made of this polymer are also characterized by slightly poor mechanical properties. From the user's perspective, the most important is proper adhesion of glue to the enamel or dentin (bone tissue from which the core of the tooth is built).

With inadequate adhesion of the adhesive, which results in insufficient adhesion of the prosthesis, or a dental bridge phenomenon of secondary caries can occur, then treatment is considerably less effective. Hence, various attempts aimed at improvement of the properties of dental adhesives based on PMMA as well as at strengthening the existing bonds between the adhesive and the prosthesis are taken.

Solhi carried out a number of syntheses, during which the surface of the nanoclays (pristine sodium montmorillonite) was grafted by poly(methyl methacrylate). Such an obtained system was characterized by a clearly better mechanical properties and exhibited higher adhesion to the dentin [37, 38].
