Preparation and Use of Porous Poly(α-Hydroxyester) Scaffolds for Bone Tissue Engineering.

Skeletal defects resulting from tumor resection, congenital abnormalities, or trauma often require surgical intervention to restore function. Current options for bone replacement include autografts, allografts, metals, ceramics, and polymeric bone cements. However, all of these materials have drawbacks, and their selection usually requires some degree of compromise. Autografts represent the ideal repair material, but are limited by availability and donor site morbidity. Allografts may be potential transmitters of disease, and also solicit immune response if not sufficiently pretreated. Ceramics suffer from slow integration and remodeling, and wear-debris from nondegradable polymeric implants may evoke chronic inflammation. Finally, metallic implants may cause atrophy of surrounding tissue through stress shielding, requiring corrective procedures.

Review: Hydrogels for cell immobilization.

Hydrogels are being investigated for mammalian cell immobilization. Their material properties can be engineered for biocompatibility, selective permeability, mechanical and chemical stability, and other requirements as specified by the application including uniform cell distribution and a given membrane thickness or mechanical strength. These aqueous gels are attractive for analytical and tissue engineering applications and can be used with immobilization in therapies for various diseases as well as to generate bioartificial organs. Recent advances have broadened the use of hydrogel cell immobilization in biomedical fields. To provide an overview of available technology, this review surveys the current developments in immobilization of mammalian cells in hydrogels. Discussions cover hydrogel requirements for use in adhesion, matrix entrapment, and microencapsulation, the respective processing methods, as well as current applications. (c) 1996 John Wiley & Sons, Inc.