Biomedical Engineering Reference
In-Depth Information
performed versus the control hybrid composite
[55]
. The nanocomposite was found to be more polish-
able than the hybrid material. After 3 years the nanocomposite was found to meet the American Dental
Association (ADA) acceptance guidelines for tooth colored restorative materials for posterior teeth and
its performance was comparable to that of human enamel. A follow-up report of the same clinical study
after 5 years
in-vivo
continued to show good clinical performance and enamel-like vertical wear resist-
ance
[56]
. A 2-year clinical study comparing conventional, nanohybrid and nanofill composites showed
the nanocomposites to have acceptable clinical performance similar to the control microhybrid material
[57]
. Similar results have been reported in another clinical study at 18 months
[58]
. A few studies have
also reported on the clinical experience with the nanoionomer Ketac Nano. Burgess et al.
[59]
reported
this material to provide improved finish, resulting in a more aesthetic restoration. Good clinical results
have also been reported at 2 years by Croll and Berg
[60]
in pediatric restorations which were found to
be superior aesthetic properties and maintained their clinical function.
2.6
CONCLUSIONS
The use of nanoparticle technology allows the formulation of dental materials with high translucency,
excellent initial polish as well as retention of gloss while maintaining mechanical properties and wear
resistance equivalent to other clinically-proven materials. Additional benefits in terms of imparting
high radiopacity and strength in dental adhesives is described. Finally, several clinical investigations
have documented the excellent performance of these materials in a variety of oral restorations.
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