Biomedical Engineering Reference
In-Depth Information
wear to abnormal wear of human teeth has not yet been established. The mechanisms
and palliative measures of abnormal wear should be directions of future research.
Wear behavior of teeth strongly depends upon individual factors, such as age,
dietary habit, and pathological effect. Thus, based upon the concept of tribological
design and optimization, individual restoration, particularly in the choice of dental
restorative materials, should be considered in clinical treatments.
In dental medicine, the failure of dental implants due to loosening has been
considered to be a result from medical reasons such as bone resorption, while
mechanical causes have not yet been investigated for dentists. In fact, the occlusal
surfaces of teeth are loaded repeatedly during mastication. Fretting may occur not
only at the fi tting surfaces between implant materials and alveolar bone but also at
interfaces of the screw joint, which can fi nally result in loosening failure. Therefore,
mechanical design, such as the choice of interference magnitude, the shape and size
of the screw surface, the value of the pretightening force, and so on, plays an
extremely signifi cant role in reducing the damage to the dental implant surface
caused by fretting wear. However, no matter how the fretting parameters are chosen,
the dental implant-bone interface is still different from the natural tooth-bone
interface. The natural good cushioning effect in the periodontal ligament is still
absent [
24
]. Perhaps the development of tissue engineering can provide us with a
new thought; that is, forming a new periodontal ligament between the dental implant
and bone can thoroughly solve the issue of fretting damage at the interface.
Therefore, for dentists, collaborative research with other scientists is indispensable
to obtain a dental implant with a longer service life.
In conclusion, even though much progress has been made in the fi eld of dental
wear, much remains to be achieved toward a systematic correlation between the
tribological behavior and structure of human teeth, a bionic design for engineering
wear system, and a clinical treatment against dental wear based upon the concept of
tribological design. Inevitably, more research directions will emerge. We hope that
this topic would help to initiate some discussion and provide some information on
what we have learned from human teeth.
References
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3. Gwinnett AJ (1992) Structure and composition of enamel. Oper Dent 5(Suppl):10-17
4. Mjör IA (1972) Human coronal dentine: structure and reactions. Oral Surg Oral Med Oral
Pathol 33:810-823
5. Lin CP, Douglas WH (1994) Structure-property relations and crack resistance at the bovine
dentin junction. J Dent Res 73:1072-1078
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7. Shimada Y, Iwamoto N, Kawashima M, Burrow MF, Tagami J (2003) Shear bond strength of
current adhesive systems to enamel, dentin and dentin-enamel junction region. Oper Dent 28:
585-590
