Biomedical Engineering Reference
In-Depth Information
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Some accepted biomaterials
Metals
Ceramics
Polymers
316L stainless steel Alumina
Ultra-high molecular weight
polyethylene
Co-Cr Alloys
Zirconia
Polyurethane
Titanium
Carbon
Ti-6Al-4V
Noble metal alloys
Hydroxyapatite
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Dental applications of some biomaterials
Metals
Ceramics
Polymers
Implants
Tooth implants
Orthodontic devices
(plates, dentures)
Parts of orthodontic
devices
Dental porcelains
Pins for anchoring
tooth
Hydroxyapatite
(coatings on metallic pins)
(ill large bone voids)
Interestingly, the separation between the three traditional
material classes (i.e., metals, ceramics, and polymers) is gradually
being replaced by keywords such as
scaffolds
and
composite
biomaterials
. This might be explained by the realization that a single
material class does not relect the complexity of highly structured
human tissues, and necessitates the use of advanced biomimetic
processing techniques to create intelligent biomaterials of similar
functionality [29, 119].
Recently, increasing interest has been shown in ceramic-polymer
composites as potential illers of bone defects [65, 143]. Three of
the most commonly used composites — calcium phosphate ceramics,
tricalcium phosphate, and hydroxyapatite — have demonstrated
adequate biocompatibility and suitable osteoconduction and
osseointegration [8]. Bioceramic glasses such as 45S5 Bioglass
®
have also exhibited the capacity to induce bone-bonding, and even
vascularization. However, these ceramics are considered too stiff and
brittle to be used alone. The addition of a ceramic to a polymer scaffold
has several advantages including combining the osteoconductivity
and bone-bonding potential of the inorganic phase with the porosity
and interconnectivity of the three-dimensional construct. The most
prominent natural polymer used to fabricate matrices in composites
is collagen type I, probably due to its prevalence in bone's extracellular
