Surface pretreatments for medical application of adhesion

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

Emotions and Technoethics

The relationship between emotions and ethics has been debated for centuries. The act of understanding emotions through the framework of ethics involves accepting that emotions are to some extent culturally dependent. By linking emotions in design to larger ethical discussions, it may be accepted that ethics and design are both technological constructions designed to shape a collective worldview. While both are cultural constructions, they are in constant dialogue with one another through social discourse and individualistic cognitive–affective appraisal processes. This chapter presents an account of technoethics that challenges ideas of ethical values embedded within technology, drawing attention to the role of human intentionality as a definitive ethical factor in human–technology relationships. The chapter problematises simplistic views of ethics and emotional technology experience to reveal the ambiguous and dynamic nature of cognitive–emotional–cultural interdependencies in technology experience.peerReviewe