Biomedical Engineering Reference
In-Depth Information
smaller machine tools, which in turn could be utilized to make even smaller machine tools and so
on, all the way down to the molecular and nanoscale level (1 nm
10
2
9
m or one-billionth of a
meter). He suggested that such nanomachines, nanorobots, and nanodevices could be ultimately
used to develop a wide range of atomically precise micro/nanoscopic instrumentation and
manufacturing tools. Feynman also discussed the storage of information on a very small scale,
writing and reading in atoms, miniaturization of computers, and building tiny machines and elec-
tronic circuits with atoms. He stated that “In the year 2000, when they look back at this age, they
will wonder why it was not until the year 1960 that anybody began to seriously move in this
direction.”
However, Feynman did not specifically use the term “nanotechnology” then. The first use of the
word “nanotechnology” has been attributed to Norio Taniguchi in a paper titled On the Basic
Concept of NanoTechnology published in 1974
[2]
. Eric Drexler, an MIT graduate took Feynman's
concept of a billion tiny factories and added the idea that they could replicate more copies of them-
selves via computer control instead of a human operator in his 1986 topic Engines of Creation: The
Coming Era of Nanotechnology, to popularize the potential of nanotechnology. Nanotechnology is
described as the multidisciplinary science of the creation of materials, devices, and systems at the
nanoscale level. It refers to the manipulation, precise placement, measurement, modeling, or manu-
facture of sub-100 nm scale matter. In other words, it has been described as the ability to work at
atomic, molecular, and supramolecular levels (on a scale of
5
100 nm) to understand, create,
and use material structures, devices, and systems with fundamentally new properties and functions
resulting from their small structure.
Nanotechnology has been approached in two ways: from the “top-down” or the “bottom-up”
approach
[3]
. The “top-down” approach is the utilization of miniaturization techniques to construct
micro/nanoscale structures from a macroscopic material or a group of materials by utilizing
machining and etching techniques. The best example of a “top-down” approach is the photolithog-
raphy technique used in the semiconductor industry to fabricate components of an integrated circuit
by etching micro/nanoscale patterns on a silicon wafer. The “bottom-up” approach refers to the
construction of macromolecular structures from atoms or molecules that have the ability to self-
organize or self-assemble to form a macroscopic structure
[4,5]
.
Nanotechnology has much more to offer than just simple miniaturization and building the
molecular structures from the atomic scale. Over the past decade, numerous discoveries and appli-
cations of nanotechnology have revolutionized multiple disciplines of science, technology, medi-
cine, and space exploration. In the field of medicine, nanotechnology has been applied in diagnosis,
prevention, and treatment of diseases. Nanomaterials are being applied in the field of pharma-
cotherapeutics toward new drug synthesis, targeted drug delivery for cancer treatment, regenerative
medicine, imaging, and gene therapy
[6,7]
.
Nanotechnology offers promising scope in dentistry to improve dental treatment, care, and pre-
vention of oral diseases. Currently, numerous nanoscale dental materials, nanocharacterization
methods, and nanofabrication techniques are being employed in dentistry to improve the biomate-
rial properties. During the last decade, the use of nanotechnology and nanoparticles has become
popular in the design and development of dental biomaterials with improved material characteris-
tics. The purpose of this chapter is to give the reader an overview of these recent developments in
nanotechnology, nanomaterials, nanoscale imaging tools, and their applications in dentistry, and
more specifically in orthodontics.
1
B
