Novel polyisobutylene/polydimethylsiloxane bicomponent networks: III. Tissue compatibility

The tissue biocompatibility of a series of novel rubbery polyisobutylene (P IB)/polydimethylsiloxane (PDMS) bicomponent networks was investigated by in vivo implantation into rats. Bicomponent networks of varying composition ( PIB wt%/PDMS wt% = 70/30, 50/50, 35/65) as well as a standard polyethylene control were implanted intraperitoneally. After eight weeks the implants an d surrounding tissue were removed for histological evaluation. In all scori ng categories (i.e. collagen thickness, fibrous tissue orientation, collage n deposition in muscle tissue, lymphocyte infiltration, angiogenesis) the P IB/PDMS bicomponent network implants elicited either less or similar tissue and cellular response than polyethylene. To determine which implant elicit ed the least tissue and cellular response overall, a weighted score includi ng collagen thickness, lymphocyte infiltration, and angiogenesis was calcul ated for each implant. According to these preliminary investigations. PIB/P DMS bicomponent networks are suitable for implant applications.