In the dental field there has been an ongoing search for a solid method to filling cavities. Dental professionals are searching for a material that will both exhibit a high polish retention, and extreme strength against high stress bearing zones. Before the beginning of nanotechnology being used in dental materials, dentists used a class of composites called microfills. Microfills were used because of their high level of original gloss and their superior ability to retain polish. However, it was missing the other half of the equation and was not regarded as a successful filling material. The microfills, although had an extremely high polish retention, were not suitable for high stress bearing areas of the dentition. Some examples these high stress areas include: class I, II, and IV restorations.
The use of nanotechnology within dental materials will make a huge difference. Working with materials at the nano level will help ...view middle of the document...
These nanofillers allowed a larger amount of filler to mix into the composite resin substance. This compaction produced a stronger composite. However, even though it may seem plausible to only use nanofillers, this material lost all fluid type movements within the filling and the rheological properties became extremely poor. Due to this discovery, there have been many attempts to mix nanomers of different sizes, to help break up the stiffness. This next idea was called the nanohybrid composite, which consisted of a blend of fillers. However, the attempts proved that this type of composite was not balanced correctly, and therefore did not produce very promising results. The little improvements within the rheological property were not significant enough for how much of the optical property was sacrificed. After being faced with this problem, nanoclusters were created. Nanoclusters were created in attempts to overcome the disadvantages of the rheological poor nanofillers and the unbalanced nanohybrid composites. Nanoclusters are different because they contain nanomeric oxides that form clusters of controlled particles that are sensibly distributed. In nanoclusters the particles can range anywhere from 5-75nm in size. With this type of distribution, the nanocluster fillers have a high filler loading, outstanding structural properties, and desirable handling features. However, since the polish retention is managed by the largest particle, this type of composite suffers greatly from the loss of gloss.
Although, the application of nano particles into dental composites are not perfect they still make better fillings than the ones dentists use today. It is clear that the nano particle technology has enabled the production of fillings that contain both esthetic and mechanical features of an ideal composite. However, before nanofilll, nanohybrid, nanoclusters, or similar composites can take place in regular practice, their success in vitro studies need to be established by more clinical, long term studies, and follow ups. There has already been one to two year clinical study follow ups but they want to still test for positive long term effects.