Keywords: dental composites, restoratives, nanofillers, inorganic-organic hybrids, sol-gel process, polycondensates, polysiloxanes, radical polymerisation, polymerisable silanes, radiopaque fillers, protective coatings, nanotechnology
Nanotechnology for dental composites
In dentistry, composites consisting of inorganic fillers such as radiopaque glass, quartz or ceramic particles and an organic resin matrix based on a mixture of dimethacrylates, are used for the restoration of teeth. Important properties of the dental restorative materials can be improved by means of nanotechnology. Inorganic-organic hybrid materials can be used as monomer matrix in dental restoratives to diminish their polymerisation shrinkage and improve their wear resistance and biocompatibility. Inorganic-organic hybrids with tailor-made properties can be created by means of sol-gel processing of hydrolytically condensable, organically modified trialkoxysilanes, which contain radically polymerisable methacrylate groups or cyclic groups capable of ring-opening polymerisation. Furthermore, nanofillers can contribute to increasing the modulus of elasticity or improving the optical properties of the dental composites and are useful as starting compounds for the synthesis of new low temperature processable dental ceramics. Moreover, well designed nano- and microstructured sol-gel components can be used for producing protective and wear resistant coatings for teeth, metal alloys, and glass fillers of special compositions.