Nanoceramics: Synthesis, Characterizations and Applications
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4.2 Nanoceramics as Dental Implants
Ceramic materials have been used as dental implants due to their advantageous
properties like compressive strength, wear resistance, radiopacity, color stability
and biocompatibility. Many such ceramic dental implants have been developed in
order to increase their durability and clinical lifetime. Dental implants get contaminated by settling of bacterial deposits especially the organic residues. Photocatalytic
activity of TiO 2 can be used to degrade the organic residues and regain biocompatibility. A unique TiO 2 nanoceramic coating was developed on Ti implants by plasma
electrolytic oxidation (PEO). The coating was able to decompose dyes like methylene blue, rhodamine B, and also pre-adsorbed lipopolysaccharide in the presence
of visible light. The coating had good osteoconductivity than untreated Ti implant
suggesting that it can be used in peri-implantitis treatments [92].
Feldspathic is an advanced ceramic material manufactured by high fusion and has
excellent aesthetic properties, opacity and translucency. It is widely used in smile
aesthetic recovery with the underlying tooth reinforcing the coating [91]. Feldspathic
and alumina added Apatite-Wollastonite glass-ceramic were prepared by sintering
MgO-CaO-SiO 2 -P 2 O 5 -Al 2 O 3 system at 1100 °C. The dental material produces an
interface that is similar in characteristics to the commercially available dental material and hence is a suitable alternate [93]. Aluminized ceramics were prepared by
incorporating metallic oxides. The recently developed glass-infiltrated aluminized
ceramic with high alumina content has greater fracture resistance and they can be
used for both anterior and posterior regions as prostheses [94, 95]. Zirconia based
ceramics contain 69% aluminum oxide and 31% zirconium oxide. It’s the best alternate for large metal-free fixed prostheses as it has good mechanical properties, clinical
longevity and biocompatibility. Yttria-stabilized zirconia is developed by adding pure
yttrium dioxide to zirconia. This material has high fracture toughness and it prevents
crack propagation commonly observed in aluminized ceramics [90].
4.3 Nanoceramics as Drug Delivery Systems
Conventional drug delivery systems have a major limitation namely, limited drug
solubility which leads to poor biodistribution, poor targeting, reduced efficacy, and
serious side effects in non-target tissues. In some treatments, a definite amount of
drug has to be maintained in the bloodstream over a stretch of time for effective treatment and faster recovery. With the conventional drug delivery method, this cannot
be ensured as fluctuations in drug level is common. This leads to overdosage to
achieve the result. Controlled and continuous in situ delivery of drugs is possible
with biocompatible nanoceramics as they act as good drug delivery system (DDS)
compared to the traditional ones such as lipids and polymers [96]. Their bioactive
behavior along with their ability to control the rate and period of drug delivery and
also target the release of drug in a specific area of the body makes them attractive for
147
4.2 Nanoceramics as Dental Implants
Ceramic materials have been used as dental implants due to their advantageous
properties like compressive strength, wear resistance, radiopacity, color stability
and biocompatibility. Many such ceramic dental implants have been developed in
order to increase their durability and clinical lifetime. Dental implants get contaminated by settling of bacterial deposits especially the organic residues. Photocatalytic
activity of TiO 2 can be used to degrade the organic residues and regain biocompatibility. A unique TiO 2 nanoceramic coating was developed on Ti implants by plasma
electrolytic oxidation (PEO). The coating was able to decompose dyes like methylene blue, rhodamine B, and also pre-adsorbed lipopolysaccharide in the presence
of visible light. The coating had good osteoconductivity than untreated Ti implant
suggesting that it can be used in peri-implantitis treatments [92].
Feldspathic is an advanced ceramic material manufactured by high fusion and has
excellent aesthetic properties, opacity and translucency. It is widely used in smile
aesthetic recovery with the underlying tooth reinforcing the coating [91]. Feldspathic
and alumina added Apatite-Wollastonite glass-ceramic were prepared by sintering
MgO-CaO-SiO 2 -P 2 O 5 -Al 2 O 3 system at 1100 °C. The dental material produces an
interface that is similar in characteristics to the commercially available dental material and hence is a suitable alternate [93]. Aluminized ceramics were prepared by
incorporating metallic oxides. The recently developed glass-infiltrated aluminized
ceramic with high alumina content has greater fracture resistance and they can be
used for both anterior and posterior regions as prostheses [94, 95]. Zirconia based
ceramics contain 69% aluminum oxide and 31% zirconium oxide. It’s the best alternate for large metal-free fixed prostheses as it has good mechanical properties, clinical
longevity and biocompatibility. Yttria-stabilized zirconia is developed by adding pure
yttrium dioxide to zirconia. This material has high fracture toughness and it prevents
crack propagation commonly observed in aluminized ceramics [90].
4.3 Nanoceramics as Drug Delivery Systems
Conventional drug delivery systems have a major limitation namely, limited drug
solubility which leads to poor biodistribution, poor targeting, reduced efficacy, and
serious side effects in non-target tissues. In some treatments, a definite amount of
drug has to be maintained in the bloodstream over a stretch of time for effective treatment and faster recovery. With the conventional drug delivery method, this cannot
be ensured as fluctuations in drug level is common. This leads to overdosage to
achieve the result. Controlled and continuous in situ delivery of drugs is possible
with biocompatible nanoceramics as they act as good drug delivery system (DDS)
compared to the traditional ones such as lipids and polymers [96]. Their bioactive
behavior along with their ability to control the rate and period of drug delivery and
also target the release of drug in a specific area of the body makes them attractive for