Cellular Responses to Nanoscale Surface Modifications of Titanium Implants for Dentistry and Bone Tissue Engineering Applications

Synthesis of nanostructured porous silica coatings on titanium and their cell adhesive and osteogenic differentiation properties

“…Several techniques and approaches are used currently to produce nanotopographic modifications of endosseous implants . Some of these approaches involve physical methods of compaction of ceramic particles to yield surfaces with nanoscale grain boundaries, chemical treatments, sandblasting/acid etching, optical lithography, galvanostatic anodization, crystal deposition, and monolayers to expose functional end groups that have specific functions .…”

Micro-bending and patterning via high energy pulse laser peening

“…In addition, it has been found that a grooved or roughened surface contributes to the osteoblast differentiation in human mesenchymal pre-osteoblastic cells, which helps to avoid longterm peri-abutment inflammation issues for the dental implant therapy with transcutaneous devices. When comparing rough versus grooved surfaces, it has been seen that the cells align with the grooves on the grooved surface, and similarly with the pattern found on the rough surface [36,37,39,40]. However, existing approaches, such as grit blasting, acid etching, or uni-directional grooving of Ti surfaces, can damage the implant and the surface quality is very difficult to control.…”

“…Without proper cell-attachment, chronic inflammation due to the lack of tissue growth around the implant device can occur, which can lead to the potential for mucosal recession or even implant loss. Studies have shown that when comparing rough versus grooved surfaces, cells align with the grooves on the grooved surface, and similarly with the pattern found on the rough surface [36,37,39,40]. Existing approaches used to create roughened or patterned implant surfaces are grit blasting, acid etching, or uni-directional grooving of Ti surfaces, however these can damage the implant and the surface quality is very difficult to control.…”

“…Another issue in the bio-industry is that titanium alloys, such as Ti-6Al-4V, are commonly used as biomedical implants because of their superior mechanical properties to pure titanium, however there is a risk of leeching toxic alloy elements into the body which can lead to long term health effects [39,40]. Due to this, pure titanium is the preferred material for these applications; however, it has limited mechanical strength, and the implants often fail due to the coupled effects of corrosion, fatigue and fracture under cyclic loading and high stresses in such an aggressive environment [49][50][51][52].…”

“…As a material starts to corrode, the dissolution of metal will lead to erosion which in turn will eventually lead to brittleness and fracture of the implant. Once the material fractures, corrosion accelerates due to an increase in the amount of exposed surface area and loss of protective oxide layer [39,40]. Corrosive fatigue can occur in titanium hip implants by simply walking, which causes cyclic loading at a frequency of about 1 Hz [54].…”