Book excerpt: This chapter focuses on adhesives used in direct physiological contact in dental and medical procedures. Activity in both areas has been quite extensive outside the United States for decades. In contrast, adhesive use in medical devices, patches, and plasters has been ongoing in the United States for a long time. In the case of medical devices, adhesion is concerned with the joining of materials such as plastics, elastomers, textiles, metals, and ceramics, which are examined in other chapters of the present volume and are covered in various references [1–6], The coverage of this chapter is devoted to applications where to adhesives are in direct contact with tissues and other live organs.