Biomedical Engineering Reference
In-Depth Information
the proximal contact area, and thereby result in food impaction and subsequent loss
of bone and periodontal attachment.
Therefore, understanding dental wear mechanisms can help dentists not only
make a rapid diagnosis, but also propose appropriate treatment methods against
tooth wear.
1.9.2
Development of Dental Materials and Design
of Implant Teeth
In the field of dental medicine, some factors, such as cost, aesthetics, biocompatibil-
ity, and hardness, have mainly been considered in order to choose artificial dental
materials. Three types of materials—metals and their alloys, ceramics, and compos-
ite—have been frequently used as restorative materials. However, the concept of
tribological design has not yet been applied to dental materials. In fact, as presented
in the next chapter, the tribological behavior of human teeth is very complex. For
example, wear behavior is quite different not only at different surfaces, such as the
enamel, or the dentin surface for a given tooth, but also for teeth at different ages. In
addition, bite force and food and drink habits also influence wear behavior and may
be different for children, young adults, and the elderly. However, until now, dentists
have rarely considered such big differences in wear behavior due to individual, nat-
ural factors; artificial dental materials should be individually chosen and designed
in order to match the behavior of the opposite tooth.
Major investigations center on dental wear occurring at the occlusual contact. In
fact, loosening and failure of the implant teeth have been occasionally encountered
after a long or short period of service. As presented in the next chapter, fretting, a
term frequently used in engineering, is mainly caused under the daily bite loading.
However, the term “fretting” has been never studied in the dental field except by
these authors. The mechanism of fretting and palliative methods against fretting
failure need to be spread and applied for implants.
The use of tribological design concepts is very important for dentists to be able
to choose current restorative materials, develop new dental materials, and design
new implant teeth with a greater service life.
1.9.3
Bionic Design
Human teeth have become the hardest organ in the body after millions of years of
evolution. Friction and wear of teeth, either natural or artificial, are unavoidable.
However, daily wear of teeth is actually slight and negligible in normal use condi-
tion, and human teeth exhibit excellent antiwear behavior. As presented in the next
chapter, five factors have been shown to play a significant role in the excellent wear
