Osseointegration on metallic implant surfaces: Effects of microgeometry and growth factor treatment

Abstract

Orthopedic implants often loosen due to the invasion of fibrous tissue. The aim of this study was to devise a novel implant surface that would speed healing adjacent to the surface, and create a stable interface for bone integration, by using a chemoattractant for bone precursor cells, and by controlling tissue migration at implant surfaces via specific surface microgeometry design. Experimental surfaces were tested in a canine implantable chamber that simulates the intramedullary bone response around total joint implants. Titanium and alloy surfaces were prepared with specific microgeometries, designed to optimize tissue attachment and control fibrous encapsulation. TGF beta, a mitogen and chemoattractant (Hunziker EB, Rosenberg LC. J Bone Joint Surg Am 1996;78:721-733) for osteoprogenitor cells, was used to recruit progenitor cells to the implant surface and to enhance their proliferation. Calcium sulfate hemihydrate (CS) was the delivery vehicle for TGF beta; CS resorbs rapidly and appears to be osteoconductive. Animals were sacrificed at 6 and 12 weeks postoperatively. Results indicated that TGFbeta can be reliably released in an active form from a calcium sulfate carrier in vivo. The growth factor had a significant effect on bone ingrowth into implant channels at an early time period, although this effect was not seen with higher doses at later periods. Adjustment of dosage should render TGF beta more potent at later time periods. Calcium sulfate treatment without TGF beta resulted in a significant increase in bone ingrowth throughout the 12-week time period studied. Bone response to the microgrooved surfaces was dramatic, causing greater ingrowth in 9 of the 12 experimental conditions. Microgrooves also enhanced the mechanical strength of CS-coated specimens. The grooved surface was able to control the direction of ingrowth. This surface treatment may result in a clinically valuable implant design to induce rapid ingrowth and a strong bone-implant interface, contributing to implant longevity.

Differences of Post-Placement Bone Implant Contact (BIC) Value of Dental Implant Coated and Not Coated With Platelet Rich Plasma (PRP)

“…PDGF also stimulates the production of fibronectin, the cell adhesion molecule used in cellular. Fogelman et al, 2012;Frenkel, 2002) Regeneration of bone-forming cells in this study was seen from the BIC parameters, shown higher in the treatment group than the control group where the difference was statistically significant (P = 0.001). This proves that the use of PRP increases the initial reaction of bone-forming cells on the surface of the dental implant.…”

The effect of phosphorylcholine‐coated materials on the inflammatory response and fibrous capsule formation: In vitro and in vivo observations

“…Fibrous capsule, the end stage of the body's reaction to the presence of a foreign material has been reported to have some benefits by isolating the implant from the body and limiting the resulting inflammatory responses that could have otherwise continued, potentially leading to rejection of the implant. In many cases, however, fibrous capsule can lead to device failure, for interference in the osseointegration process, 15 causing poor tissuedevice contact that may also lead to infection, 16 or restriction of nutrient supply to and from the device. 17 A multitude of studies have been performed with different biocompatible medical implants, comparing different biomaterials, their sizes, surface morphologies, and implantation sites.…”

Dental Implant Surface Enhancement and Osseointegration

“…This process results in titanium surface microstructures with greatly increased hardness, corrosion resistance, and a high degree of purity with a standard roughness and thicker oxide layer (Gaggl et al, 2000, Hallgren et al, 2003. Biological studies evaluating the role of titanium ablation topography and chemical properties showed the potential of the grooved surface to orientate osteoblast cell attachment and control the direction of ingrowth (Frenkel et al, 2002).…”