Top: HA coating on cp-Ti dental implants. Low magnification to show uniformity.
Middle: HA coating on cp-Ti dental implants. High magnification to show nanoscale features and nano-porosity.
Bottom: Cross-section of HA coating to show the thickness of coating (~ 60 µm) and its uniformity
One application area that NanoMech has been developing based on its unique NanoSpray coating technology is coatings for implants. The novelty of NanoMech's technology lies in how the coating is applied onto the implant. NanoMech's patented Nanospray electrostatic deposition process, followed by microwave sintering, results in improved mechanical properties and biological performance of the implant coating. NanoMech's technology provides better adhesion and better control of the coating's pore size and structure. This can provide shorter healing times, a lower failure rate of the implant procedure and longer lasting implants. NanoMech has initially focused on hydroxyapatite (HAp) nanoparticle coatings for dental implants.
Currently available HAp-coated implants are fabricated using coating technologies (e.g. plasma spray) that have a tendency to cause separation from the titanium implant. In addition, while a functionally-graded coating has the characteristics of varied chemistry and/or structure across the coating thickness (as is characteristic of living tissue), and if deposited properly, can maintain the superior performance of nanoparticles (hardness, toughness, wear-resistance, and enhanced bioactivity) while offering improved osseointegration and bonding, currently available coatings fabricated using other technologies have difficulty achieving these desirable characteristics. Those conventional technologies require high temperatures in the manufacturing process which can degrade the coating materials, and cannot readily coat complex geometrical structures.
NanoMech's approach combines the company's Nanospray process which can apply nanoparticles of various materials at room temperature conditions, with microwave or laser sintering to produce dental implants with controlled thickness (submicron to micron) and excellent adhesion for improved durability, controlled pore sizes for tissue growth promotion, minimal physical distortion of the implants, and better osseointegration for faster healing times.
The novel approach eliminates the formation of amorphous HAp which is easily absorbed into body fluid and negatively affects adhesion, and does not require the high temperatures (with subsequent degradation of the coating materials) associated with other conventional coating technologies. It allows coating to be applied to various surfaces having different textures and three-dimensional geometries, and most importantly, allows the nanostructured character of the coating materials to be maintained, enhancing tissue growth.