Biomedical Engineering Reference
In-Depth Information
X
=10mm
F
=100
g
100
g
10mm=1000
g
mm
FIGURE 12.7
The moment produced by the force (F) equals the magnitude of the force F (100g) multiplied by the
perpendicular distance between the center of resistance and the line of action of the force (X
5
10 mm).
Since the teeth root lengths are different among individuals, this consequently changes the
length of the moment arms and the applied moments using similar forces. In order to apply biologi-
cally tolerable forces and moments to the teeth to efficiently move teeth with minimal adverse
effects such as EARR depending on the individual's intrinsic susceptibility, researchers have been
working to develop brackets that can carry three-dimensional mechanical sensors in the bracket
bases to measure in three dimensions the real-time forces and moments applied to the teeth. This
would facilitate the orthodontist adjusting these forces
should they exceed biologically
acceptable limits.
In order to achieve this, microsensors have been proposed in the recent literature. Lapatki et al.
in 2007 reported on the introduction of a “smart” bracket for multidimensional force and moment
measurement
[19,20]
. They reported on a large-scale prototype bracket that utilized microsystem
chip encapsulation. Development of a nanosystem chip that can be encapsulated into small low-
profile contemporary bracket systems with reduced mesiodistal and occlusogingival dimensions
will allow clinical testing of the utilization of this technology.
12.6
Future applications of nanotechnology in orthodontics
Although nanotechnology application in orthodontics is considered to be in its infancy, there is a
huge potential application of nanotechnology in orthodontics including nanodesigned orthodontic
bonding materials, possible nanovector for gene delivery for mandibular growth stimulation, and
nano-LIPUS devices. Also, nanomechanical sensors can be fabricated and be incorporated into the
base of orthodontic brackets and tubes in order to provide real-time feedback about the applied
orthodontic forces. This real-time feedback allows the orthodontist to adjust the applied force to be
within a biological range to efficiently move teeth with minimal side effects. In a fast growing
world of nanotechnology, the hope would be to get these technologies into clinical application
