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Surface pretreatments for medical application of adhesion.

Erli HJ, Marx R, Paar O, Niethard FU, Weber M, Wirtz DC - Biomed Eng Online (2003)

Bottom Line: Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body.The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m).This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Prosthetic Dentistry, Section of Dental Materials, University Hospital of the University of Technology, Aachen, Germany. herli@ukaachen.de

ABSTRACT
Medical implants and prostheses (artificial hips, tendono- and ligament plasties) usually are multi-component systems that may be machined from one of three material classes: metals, plastics and ceramics. Typically, the body-sided bonding element is bone. The purpose of this contribution is to describe developments carried out to optimize the techniques, connecting prosthesis to bone, to be joined by an adhesive bone cement at their interface. Although bonding of organic polymers to inorganic or organic surfaces and to bone has a long history, there remains a serious obstacle in realizing long-term high-bonding strengths in the in vivo body environment of ever present high humidity. Therefore, different pretreatments, individually adapted to the actual combination of materials, are needed to assure long term adhesive strength and stability against hydrolysis. This pretreatment for metal alloys may be silica layering; for PE-plastics, a specific plasma activation; and for bone, amphiphilic layering systems such that the hydrophilic properties of bone become better adapted to the hydrophobic properties of the bone cement. Amphiphilic layering systems are related to those developed in dentistry for dentine bonding. Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body. The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m). This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body.

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Bond strength vs layer thickness. Layer thicknesses grouped into three classes. Material: unalloyed Titanium samples adhered together with Refobacin®-Palacos®R. Before adhering together, samples were pre-coated by a protecting layer out of PMMA and BisGMA, similar to the layer protecting the silica layer on surface of the artificial stem. Without/with hydrolytic load 30 to 360 days; demineralized water, 37°C.
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Figure 5: Bond strength vs layer thickness. Layer thicknesses grouped into three classes. Material: unalloyed Titanium samples adhered together with Refobacin®-Palacos®R. Before adhering together, samples were pre-coated by a protecting layer out of PMMA and BisGMA, similar to the layer protecting the silica layer on surface of the artificial stem. Without/with hydrolytic load 30 to 360 days; demineralized water, 37°C.

Mentions: Experimental investigations of "dependence of bond strength on layer thickness with and without humid load" (Figs. 4 and 5), "dependence of bond strength on different periods of humid load and kind of alloys" (Figs. 6 and 7), and "crack concentration near the boundary between bone cement and metal stem" (Fig. 8) will be presented below. These studies confirm the long-term hydrolytic stability and the efficiency of the layer system. Particularly significant is how the dramatic reduction of development of cracks for coated stems underlines the potentiality of the new technology for cemented orthopedic femoral implants.


Surface pretreatments for medical application of adhesion.

Erli HJ, Marx R, Paar O, Niethard FU, Weber M, Wirtz DC - Biomed Eng Online (2003)

Bond strength vs layer thickness. Layer thicknesses grouped into three classes. Material: unalloyed Titanium samples adhered together with Refobacin®-Palacos®R. Before adhering together, samples were pre-coated by a protecting layer out of PMMA and BisGMA, similar to the layer protecting the silica layer on surface of the artificial stem. Without/with hydrolytic load 30 to 360 days; demineralized water, 37°C.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC222922&req=5

Figure 5: Bond strength vs layer thickness. Layer thicknesses grouped into three classes. Material: unalloyed Titanium samples adhered together with Refobacin®-Palacos®R. Before adhering together, samples were pre-coated by a protecting layer out of PMMA and BisGMA, similar to the layer protecting the silica layer on surface of the artificial stem. Without/with hydrolytic load 30 to 360 days; demineralized water, 37°C.
Mentions: Experimental investigations of "dependence of bond strength on layer thickness with and without humid load" (Figs. 4 and 5), "dependence of bond strength on different periods of humid load and kind of alloys" (Figs. 6 and 7), and "crack concentration near the boundary between bone cement and metal stem" (Fig. 8) will be presented below. These studies confirm the long-term hydrolytic stability and the efficiency of the layer system. Particularly significant is how the dramatic reduction of development of cracks for coated stems underlines the potentiality of the new technology for cemented orthopedic femoral implants.

Bottom Line: Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body.The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m).This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Prosthetic Dentistry, Section of Dental Materials, University Hospital of the University of Technology, Aachen, Germany. herli@ukaachen.de

ABSTRACT
Medical implants and prostheses (artificial hips, tendono- and ligament plasties) usually are multi-component systems that may be machined from one of three material classes: metals, plastics and ceramics. Typically, the body-sided bonding element is bone. The purpose of this contribution is to describe developments carried out to optimize the techniques, connecting prosthesis to bone, to be joined by an adhesive bone cement at their interface. Although bonding of organic polymers to inorganic or organic surfaces and to bone has a long history, there remains a serious obstacle in realizing long-term high-bonding strengths in the in vivo body environment of ever present high humidity. Therefore, different pretreatments, individually adapted to the actual combination of materials, are needed to assure long term adhesive strength and stability against hydrolysis. This pretreatment for metal alloys may be silica layering; for PE-plastics, a specific plasma activation; and for bone, amphiphilic layering systems such that the hydrophilic properties of bone become better adapted to the hydrophobic properties of the bone cement. Amphiphilic layering systems are related to those developed in dentistry for dentine bonding. Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body. The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m). This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body.

Show MeSH
Related in: MedlinePlus