Biomedical Engineering Reference
In-Depth Information
phosphate ions are released from the CaP coating in the peri-implant region and saturate body fluids to
precipitate a biological apatite, which serves as a substrate for osteoblastic cells producing bone tissue.
Several authors have shown the benefit of using CaP-coated titanium implants for improving the osseo-
integration
[72,73]
. In particular, Le Guehennec et al.
[21]
have studied the osseointegration of four
implant surfaces in the femoral epiphyses of rabbits after 2 and 8 weeks of healing. In this study, the
bone-implant contact and bone growth inside the chambers were compared for four different implant
surfaces and shown that biomimetic coating method may enhance the bone apposition onto titanium.
In order to prevent coating delamination and implant loosening, the CaP coating should dissolve or
degrade under osteoclastic activity at a similar rate than bone apposition. The final result should be
a direct bone-implant coating without the presence of fibrous tissue. Another advantage of these CaP
coatings is related to their preparation by biomimetic methods at physiological temperature and pH
from simulated body fluids. CaP crystals have characteristics that resemble bone mineral in term of
size and composition. Furthermore, it is possible to incorporate biologically active drugs such as anti-
biotics or growth factors during the precipitation of CaP coatings on Ti implants
[74]
. These molecules
could be locally and gradually released in the peri-implant region for either preventing bacterial infec-
tions or stimulating bone growth.
5.6
CONCLUSION
Many reports have shown that nanometer-controlled surfaces have a great effect on early events such
as the adsorption of proteins, blood clot formation, and cell behaviors occurring upon implantation
of dental implants. These early events have an effective impact on the migration, adhesion, and dif-
ferentiation of MSCs. Nanostructured surfaces may control the differentiation pathways into specific
lineages and ultimately direct the nature of peri-implant tissues. Despite an active research in dental
implants, the ideal surface for predictive tissue integration remains a challenge.
Acknowledgments
The authors are grateful to Jean-Charles Ricquier for contribution in figures preparation. We acknowledge the
pharmaceutical company SERVIER for using some drawings taken from their website.
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