Limits...
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.

Show MeSH

Related in: MedlinePlus

Vapor pressure of silicon monoxide vs. temperature on linear (on the right) and logarithmic scale (on the left).
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC222922&req=5

Figure 1: Vapor pressure of silicon monoxide vs. temperature on linear (on the right) and logarithmic scale (on the left).

Mentions: Silicon monoxide is evaporated in a high vacuum atmosphere (p ≈ 0.8...3 * 10-5 mbar) by resistance heating of an evaporation boat loaded with granulated silicon monoxide. The inner part of the boat has three compartments. Two baskets on either end are filled with silicon monoxide granulate. Above the central basket, which is empty, there is a round chimney through which the vapor stream passes. A baffle extending down from the cover completely surrounds each basket. In addition to the baffles around the baskets containing the silicon monoxide, the cover has a lip that fits snugly and overhangs the boat on both sides. The ends are sealed as the cover and evaporation chamber clamp together to form the electrical terminations of the evaporator. Thermal shielding surrounds the evaporator and is attached so that the shields do not produce undesirable cold spots in the evaporation chambers. After loading with about 3 g of silicon monoxide, the chamber is electrically heated to 1150± 2°C. The temperature is measured by means of a thermocouple that is mounted in one of the baskets that is filled with the silicon monoxide. At this temperature, silicon monoxide has a vapor pressure of about 10-2 mbar (Fig. 1), note that silicon monoxide sublimes and does not dissociate significantly during sublimation. Silicon monoxide is also widely used in optical coating technology, for electrically conducting films, and for corrosion-protective coatings [25-27].


Surface pretreatments for medical application of adhesion.

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

Vapor pressure of silicon monoxide vs. temperature on linear (on the right) and logarithmic scale (on the left).
© Copyright Policy
Related In: Results  -  Collection

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

Figure 1: Vapor pressure of silicon monoxide vs. temperature on linear (on the right) and logarithmic scale (on the left).
Mentions: Silicon monoxide is evaporated in a high vacuum atmosphere (p ≈ 0.8...3 * 10-5 mbar) by resistance heating of an evaporation boat loaded with granulated silicon monoxide. The inner part of the boat has three compartments. Two baskets on either end are filled with silicon monoxide granulate. Above the central basket, which is empty, there is a round chimney through which the vapor stream passes. A baffle extending down from the cover completely surrounds each basket. In addition to the baffles around the baskets containing the silicon monoxide, the cover has a lip that fits snugly and overhangs the boat on both sides. The ends are sealed as the cover and evaporation chamber clamp together to form the electrical terminations of the evaporator. Thermal shielding surrounds the evaporator and is attached so that the shields do not produce undesirable cold spots in the evaporation chambers. After loading with about 3 g of silicon monoxide, the chamber is electrically heated to 1150± 2°C. The temperature is measured by means of a thermocouple that is mounted in one of the baskets that is filled with the silicon monoxide. At this temperature, silicon monoxide has a vapor pressure of about 10-2 mbar (Fig. 1), note that silicon monoxide sublimes and does not dissociate significantly during sublimation. Silicon monoxide is also widely used in optical coating technology, for electrically conducting films, and for corrosion-protective coatings [25-27].

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