Biomedical Engineering Reference
In-Depth Information
7.8.7
Enhancing biomimetic remineralization
Biomimetic remineralization is a process that allows remineralization of dentinal collagen fibrils
around and within collagen that still have intermolecular cross-links, like collagen fibrils in caries-
affected dentin and phosphoric acid demineralized dentin. Biomimetic remineralization helps the
rebuilding of dentin minerals in the same hierarchical pattern of apatite nanocrystals deposition
both intrafibrillar and interfibrillar.
Tay and Pashly
[73]
suggested a guided remineralization of partially demineralized human den-
tin where they used set white Portland cement as a source of Ca ions in a phosphate-containing
fluid to precipitate apatite nanocrystals around demineralized collagen. When polyvinyl phosphonic
acid and PAA were included, these nanoprecursors were attracted to the acid-demineralized colla-
gen matrix and transformed into polyelectrolyte-stabilized apatite nanocrystals that assembled along
the microfibrils (intrafibrillar remineralization) and surface of the collagen fibrils (interfibrillar
remineralization). Transition from nanocrystals to larger apatite platelets probably occurred via the
formation of mesocrystal intermediates. Guided tissue remineralization is potentially useful in the
remineralization of acid-etched dentin that is incompletely infiltrated by dentin adhesives as well as
partially demineralized caries-affected dentin. Gandolfi et al.
[74]
suggested the use of bioactive
“smart” composites containing reactive calcium-silicate Portland-derived mineral powder as
tailored filler. This innovative method for the biomimetic remineralization of apatite-depleted
dentin surfaces and for preventing the demineralization of hypomineralized/carious dentin could be
potentially great advantage in clinical applications.
7.9
Future prospective of nanotechnology in the field of
adhesive dentistry
7.9.1
On-demand antibacterial adhesives
Welch et al.
[75]
incorporated TiO
2
nanoparticles in dental adhesives aiming at achieving the com-
bined features of bioactivity and on-demand bactericidal effect. The photocatalytic activity of adhe-
sives containing TiO
2
nanoparticles, initiated by UV irradiation, proved to interfere with bacterial
activity. Also TiO
2
nanoparticles-containing adhesives were found to have the potential of tooth
remineralization in simulated body fluids. This could open up the potential to create dental adhe-
sives that reduce the incidence of secondary caries and promote closure of gaps forming at the
interface toward the tooth via remineralization of adjacent tooth substance as well as prevention of
bacterial infections via on-demand UV irradiation.
7.9.2
Improving adhesive polymerization through
catalytic activity of nanoparticles
Nanoparticles could improve DC of adhesive polymers yielding an adhesive layer with improved
mechanical properties and resistance to degradation. Yasumoto et al.
[76]
used colloidal platinum
nanoparticles as a pretreatment to dentin after acid etching and before adhesive application to
improve the resin polymerization resulting in enhanced bond strength. Based on the same principle,
