How often do you wish
your fillings did more than fill the hole that once was a cavity? Researchers
have now come up with a new preventative measure against recurrent decay.
In today’s dentistry there are several types of restorative materials
used; such as gold, silver, and nickel alloys for indirect restorations and
amalgam or composite resins for direct. For the sake of simplicity, the focus
of this article is centered around direct restorations that utilize amalgam and
composite resin.
Amalgam alloy
restorations are commonly known as the metal or silver fillings. Composed of
silver, tin, and mercury, amalgam has a long history of use in
the field of dentistry due to its longevity and ability to withstand a
wide range of clinical placement conditions. While amalgam is a
dependable restoration material, patients are increasingly turning to composite
resins for aesthetic and environmental purposes.
When in comparison,
composite resins or commonly known as white fillings, do not have the longevity
of amalgam alloys. Advantages are found in other aspects such as reduced tooth
structure loss during caries removal, aesthetic purposes as previously
mentioned, and stronger bonding capabilities with the surface of the tooth.
Due to advances in the
field of dentistry, composite resins are typically considered the primary
choice of restorative material by many dentists for direct restorations.
In a study published December 2013 by “Reactive & Functional Polymers”,
researchers explored the viability of bacteria resistant composites by adding
antibacterial properties to composite resin component. Resin material is
made up of three primary components; a polymerizable resin matrix, silane
coupling agents, and glass filler particles. In layman’s terms, the
polymerizable resin matrix is what holds composite material together. If
you were to look at a carbon fiber part, the resin matrix would resemble the
clear material known as epoxy of which serves to give shape to the part and
provide support for the carbon fiber fabric within. The next component,
silane coupling agents, are what provide a stable bond between organic and
inorganic components of the composite. Another example in layman’s terms
is how silane coupling agents are similar to the adhesive effect of superglue
bonding your hand to a piece of plastic. Lastly, glass filler particles
are used to strengthen the composite while reducing the amount of matrix
material.
To achieve the desired
results, the researchers took two approaches. The first approach utilized
a release mechanism within the filler component that allowed antibacterial
agents such as sodium fluoride to diffuse into the adjacent tissue of the
filling to proactively prevent recurrent decay. The second approach
utilized silver supported fillers as a non-release mechanism. This
approach focused on the silver component of the filler disrupting the outer
cell membrane of harmful bacteria.
Beyth, N., Farah, S., Domb, A. J., & Weiss, E. I. (2013). Antibacterial dental resin composites. Reactive and Functional Polymers, 75, 81. doi:10.1016/j.reactfunctpolym.2013.11.011